Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3437 insertions, 0 deletions

diff --git a/src/client/SyntheticClient.cc b/src/client/SyntheticClient.cc
new file mode 100644
index 000000000..9ef5ccf19
--- /dev/null
+++ b/src/client/SyntheticClient.cc
@@ -0,0 +1,3437 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- 
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software 
+ * Foundation.  See file COPYING.
+ * 
+ */
+
+#include "include/compat.h"
+
+#include <iostream>
+#include <sstream>
+
+
+#include "common/config.h"
+#include "SyntheticClient.h"
+#include "osdc/Objecter.h"
+#include "osdc/Filer.h"
+
+
+#include "include/filepath.h"
+#include "common/perf_counters.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <utime.h>
+#include <math.h>
+#include <sys/statvfs.h>
+
+#include "common/errno.h"
+#include "include/ceph_assert.h"
+#include "include/cephfs/ceph_ll_client.h"
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_client
+#undef dout_prefix
+#define dout_prefix *_dout << "client." << (whoami >= 0 ? whoami:client->get_nodeid()) << " "
+
+// traces
+//void trace_include(SyntheticClient *syn, Client *cl, string& prefix);
+//void trace_openssh(SyntheticClient *syn, Client *cl, string& prefix);
+
+int num_client = 1;
+list<int> syn_modes;
+list<int> syn_iargs;
+list<string> syn_sargs;
+int syn_filer_flags = 0;
+
+void parse_syn_options(vector<const char*>& args)
+{
+  vector<const char*> nargs;
+
+  for (unsigned i=0; i<args.size(); i++) {
+    if (strcmp(args[i],"--num-client") == 0) {
+      num_client = atoi(args[++i]);
+      continue;
+    }
+    if (strcmp(args[i],"--syn") == 0) {
+      ++i;
+
+      if (strcmp(args[i], "mksnap") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_MKSNAP);
+	syn_sargs.push_back(args[++i]); // path
+	syn_sargs.push_back(args[++i]); // name
+      }
+      else if (strcmp(args[i], "rmsnap") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_RMSNAP);
+	syn_sargs.push_back(args[++i]); // path
+	syn_sargs.push_back(args[++i]); // name
+      } else if (strcmp(args[i], "mksnapfile") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_MKSNAPFILE);
+	syn_sargs.push_back(args[++i]); // path
+      } else if (strcmp(args[i],"rmfile") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_RMFILE );
+      } else if (strcmp(args[i],"writefile") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_WRITEFILE );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"wrshared") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_WRSHARED );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"writebatch") == 0) {
+          syn_modes.push_back( SYNCLIENT_MODE_WRITEBATCH );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"readfile") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_READFILE );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"readwriterandom") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_RDWRRANDOM );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"readwriterandom_ex") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_RDWRRANDOM_EX );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"overloadosd0") == 0) {
+	syn_modes.push_back( SYNCLIENT_MODE_OVERLOAD_OSD_0 );
+	syn_iargs.push_back( atoi(args[++i]) );
+	syn_iargs.push_back( atoi(args[++i]) );
+	syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"readshared") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_READSHARED );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"rw") == 0) {
+        int a = atoi(args[++i]);
+        int b = atoi(args[++i]);
+        syn_modes.push_back( SYNCLIENT_MODE_WRITEFILE );
+        syn_iargs.push_back( a );
+        syn_iargs.push_back( b );
+        syn_modes.push_back( SYNCLIENT_MODE_READFILE );
+        syn_iargs.push_back( a );
+        syn_iargs.push_back( b );
+      } else if (strcmp(args[i],"dumpplacement") == 0) {
+	syn_modes.push_back( SYNCLIENT_MODE_DUMP );
+	syn_sargs.push_back( args[++i] );   
+      } else if (strcmp(args[i],"dropcache") == 0) {
+	syn_modes.push_back( SYNCLIENT_MODE_DROPCACHE );
+      } else if (strcmp(args[i],"makedirs") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_MAKEDIRS );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"makedirmess") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_MAKEDIRMESS );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"statdirs") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_STATDIRS );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"readdirs") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_READDIRS );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"makefiles") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_MAKEFILES );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"makefiles2") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_MAKEFILES2 );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"linktest") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_LINKTEST );
+      } else if (strcmp(args[i],"createshared") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_CREATESHARED );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"openshared") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_OPENSHARED );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"createobjects") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_CREATEOBJECTS );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"objectrw") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_OBJECTRW );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"walk") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_FULLWALK );
+        //syn_sargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"randomwalk") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_RANDOMWALK );
+        syn_iargs.push_back( atoi(args[++i]) );       
+      } else if (strcmp(args[i],"trace") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_TRACE );
+        syn_sargs.push_back( args[++i] );
+        syn_iargs.push_back( atoi(args[++i]) );
+	syn_iargs.push_back(1);// data
+      } else if (strcmp(args[i],"mtrace") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_TRACE );
+        syn_sargs.push_back( args[++i] );
+        syn_iargs.push_back( atoi(args[++i]) );
+	syn_iargs.push_back(0);// no data
+      } else if (strcmp(args[i],"thrashlinks") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_THRASHLINKS );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"foo") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_FOO );
+      } else if (strcmp(args[i],"until") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_UNTIL );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"sleepuntil") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_SLEEPUNTIL );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"only") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_ONLY );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"onlyrange") == 0) {
+        syn_modes.push_back( SYNCLIENT_MODE_ONLYRANGE );
+        syn_iargs.push_back( atoi(args[++i]) );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"sleep") == 0) { 
+        syn_modes.push_back( SYNCLIENT_MODE_SLEEP );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"randomsleep") == 0) { 
+        syn_modes.push_back( SYNCLIENT_MODE_RANDOMSLEEP );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"opentest") == 0) { 
+        syn_modes.push_back( SYNCLIENT_MODE_OPENTEST );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"optest") == 0) {
+	syn_modes.push_back( SYNCLIENT_MODE_OPTEST );
+        syn_iargs.push_back( atoi(args[++i]) );
+      } else if (strcmp(args[i],"truncate") == 0) { 
+        syn_modes.push_back( SYNCLIENT_MODE_TRUNCATE );
+	syn_sargs.push_back(args[++i]);
+        syn_iargs.push_back(atoi(args[++i]));
+      } else if (strcmp(args[i],"importfind") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_IMPORTFIND);
+	syn_sargs.push_back(args[++i]);
+	syn_sargs.push_back(args[++i]);
+	syn_iargs.push_back(atoi(args[++i]));
+      } else if (strcmp(args[i], "lookuphash") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_LOOKUPHASH);
+	syn_sargs.push_back(args[++i]);
+	syn_sargs.push_back(args[++i]);
+	syn_sargs.push_back(args[++i]);
+      } else if (strcmp(args[i], "lookupino") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_LOOKUPINO);
+	syn_sargs.push_back(args[++i]);
+      } else if (strcmp(args[i], "chunkfile") == 0) {
+	syn_modes.push_back(SYNCLIENT_MODE_CHUNK);
+	syn_sargs.push_back(args[++i]);
+      } else {
+        cerr << "unknown syn arg " << args[i] << std::endl;
+        ceph_abort();
+      }
+    }
+    else if (strcmp(args[i], "localize_reads") == 0) {
+      cerr << "set CEPH_OSD_FLAG_LOCALIZE_READS" << std::endl;
+      syn_filer_flags |= CEPH_OSD_FLAG_LOCALIZE_READS;
+    }
+    else {
+      nargs.push_back(args[i]);
+    }
+  }
+
+  args = nargs;
+}
+
+
+SyntheticClient::SyntheticClient(StandaloneClient *client, int w)
+{
+  this->client = client;
+  whoami = w;
+  thread_id = 0;
+  
+  did_readdir = false;
+
+  run_only = -1;
+  exclude = -1;
+
+  this->modes = syn_modes;
+  this->iargs = syn_iargs;
+  this->sargs = syn_sargs;
+
+  run_start = ceph_clock_now();
+}
+
+
+
+
+#define DBL 2
+
+void *synthetic_client_thread_entry(void *ptr)
+{
+  SyntheticClient *sc = static_cast<SyntheticClient*>(ptr);
+  //int r = 
+  sc->run();
+  return 0;//(void*)r;
+}
+
+string SyntheticClient::get_sarg(int seq) 
+{
+  string a;
+  if (!sargs.empty()) {
+    a = sargs.front(); 
+    sargs.pop_front();
+  }
+  if (a.length() == 0 || a == "~") {
+    char s[30];
+    snprintf(s, sizeof(s), "syn.%lld.%d", (long long)client->whoami.v, seq);
+    a = s;
+  } 
+  return a;
+}
+
+int SyntheticClient::run()
+{
+  UserPerm perms = client->pick_my_perms();
+  dout(15) << "initing" << dendl;
+  int err = client->init();
+  if (err < 0) {
+    dout(0) << "failed to initialize: " << cpp_strerror(err) << dendl;
+    return -1;
+  }
+
+  dout(15) << "mounting" << dendl;
+  err = client->mount("", perms);
+  if (err < 0) {
+    dout(0) << "failed to mount: " << cpp_strerror(err) << dendl;
+    client->shutdown();
+    return -1;
+  }
+
+  //run_start = ceph_clock_now(client->cct);
+  run_until = utime_t(0,0);
+  dout(5) << "run" << dendl;
+
+  int seq = 0;
+
+  for (list<int>::iterator it = modes.begin();
+       it != modes.end();
+       ++it) {
+    int mode = *it;
+    dout(3) << "mode " << mode << dendl;
+
+    switch (mode) {
+
+
+      // WHO?
+
+    case SYNCLIENT_MODE_ONLY:
+      {
+        run_only = iargs.front();
+        iargs.pop_front();
+        if (run_only == client->get_nodeid())
+          dout(2) << "only " << run_only << dendl;
+      }
+      break;
+    case SYNCLIENT_MODE_ONLYRANGE:
+      {
+        int first = iargs.front();
+        iargs.pop_front();
+        int last = iargs.front();
+        iargs.pop_front();
+        if (first <= client->get_nodeid() &&
+	    last > client->get_nodeid()) {
+	  run_only = client->get_nodeid();
+          dout(2) << "onlyrange [" << first << ", " << last << ") includes me" << dendl;
+	} else
+	  run_only = client->get_nodeid().v+1;  // not me
+      }
+      break;
+    case SYNCLIENT_MODE_EXCLUDE:
+      {
+        exclude = iargs.front();
+        iargs.pop_front();
+        if (exclude == client->get_nodeid()) {
+	  run_only = client->get_nodeid().v + 1;
+          dout(2) << "not running " << exclude << dendl;
+	} else
+	  run_only = -1;
+      }
+      break;
+
+      // HOW LONG?
+
+    case SYNCLIENT_MODE_UNTIL:
+      {
+        int iarg1 = iargs.front();
+        iargs.pop_front();
+	if (run_me()) {
+	  if (iarg1) {
+	    dout(2) << "until " << iarg1 << dendl;
+	    utime_t dur(iarg1,0);
+	    run_until = run_start + dur;
+	  } else {
+	    dout(2) << "until " << iarg1 << " (no limit)" << dendl;
+	    run_until = utime_t(0,0);
+	  }
+	}
+      }
+      break;
+
+
+      // ...
+
+    case SYNCLIENT_MODE_FOO:
+      if (run_me()) {
+	foo();
+      }
+      did_run_me();
+      break;
+
+    case SYNCLIENT_MODE_RANDOMSLEEP:
+      {
+        int iarg1 = iargs.front();
+        iargs.pop_front();
+        if (run_me()) {
+          srand(time(0) + getpid() + client->whoami.v);
+          sleep(rand() % iarg1);
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_SLEEP:
+      {
+        int iarg1 = iargs.front();
+        iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "sleep " << iarg1 << dendl;
+          sleep(iarg1);
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_SLEEPUNTIL:
+      {
+        int iarg1 = iargs.front();
+        iargs.pop_front();
+        if (iarg1 && run_me()) {
+          dout(2) << "sleepuntil " << iarg1 << dendl;
+          utime_t at = ceph_clock_now() - run_start;
+          if (at.sec() < iarg1)
+            sleep(iarg1 - at.sec());
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_RANDOMWALK:
+      {
+        int iarg1 = iargs.front();
+        iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "randomwalk " << iarg1 << dendl;
+          random_walk(iarg1);
+        }
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_DROPCACHE:
+      {
+	client->sync_fs();
+	client->drop_caches();
+      }
+      break;
+
+    case SYNCLIENT_MODE_DUMP:
+      {
+	string sarg1 = get_sarg(0);
+	if (run_me()) {
+	  dout(2) << "placement dump " << sarg1 << dendl;
+	  dump_placement(sarg1);
+	}
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_MAKEDIRMESS:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "makedirmess " << sarg1 << " " << iarg1 << dendl;
+          make_dir_mess(sarg1.c_str(), iarg1);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_MAKEDIRS:
+      {
+        string sarg1 = get_sarg(seq++);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        int iarg3 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "makedirs " << sarg1 << " " << iarg1 << " " << iarg2 << " " << iarg3 << dendl;
+          make_dirs(sarg1.c_str(), iarg1, iarg2, iarg3);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_STATDIRS:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        int iarg3 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "statdirs " << sarg1 << " " << iarg1 << " " << iarg2 << " " << iarg3 << dendl;
+          stat_dirs(sarg1.c_str(), iarg1, iarg2, iarg3);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_READDIRS:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        int iarg3 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "readdirs " << sarg1 << " " << iarg1 << " " << iarg2 << " " << iarg3 << dendl;
+          read_dirs(sarg1.c_str(), iarg1, iarg2, iarg3);
+        }
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_THRASHLINKS:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        int iarg3 = iargs.front();  iargs.pop_front();
+        int iarg4 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "thrashlinks " << sarg1 << " " << iarg1 << " " << iarg2 << " " << iarg3 << dendl;
+          thrash_links(sarg1.c_str(), iarg1, iarg2, iarg3, iarg4);
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_LINKTEST:
+      {
+	if (run_me()) {
+	  link_test();
+	}
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_MAKEFILES:
+      {
+        int num = iargs.front();  iargs.pop_front();
+        int count = iargs.front();  iargs.pop_front();
+        int priv = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "makefiles " << num << " " << count << " " << priv << dendl;
+          make_files(num, count, priv, false);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_MAKEFILES2:
+      {
+        int num = iargs.front();  iargs.pop_front();
+        int count = iargs.front();  iargs.pop_front();
+        int priv = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "makefiles2 " << num << " " << count << " " << priv << dendl;
+          make_files(num, count, priv, true);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_CREATESHARED:
+      {
+        string sarg1 = get_sarg(0);
+        int num = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "createshared " << num << dendl;
+          create_shared(num);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_OPENSHARED:
+      {
+        string sarg1 = get_sarg(0);
+        int num = iargs.front();  iargs.pop_front();
+        int count = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "openshared " << num << dendl;
+          open_shared(num, count);
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_CREATEOBJECTS:
+      {
+        int count = iargs.front();  iargs.pop_front();
+        int size = iargs.front();  iargs.pop_front();
+        int inflight = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "createobjects " << count << " of " << size << " bytes"
+		  << ", " << inflight << " in flight" << dendl;
+          create_objects(count, size, inflight);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_OBJECTRW:
+      {
+        int count = iargs.front();  iargs.pop_front();
+        int size = iargs.front();  iargs.pop_front();
+        int wrpc = iargs.front();  iargs.pop_front();
+        int overlap = iargs.front();  iargs.pop_front();
+        int rskew = iargs.front();  iargs.pop_front();
+        int wskew = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          dout(2) << "objectrw " << count << " " << size << " " << wrpc 
+		  << " " << overlap << " " << rskew << " " << wskew << dendl;
+          object_rw(count, size, wrpc, overlap, rskew, wskew);
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_FULLWALK:
+      {
+        string sarg1;// = get_sarg(0);
+        if (run_me()) {
+          dout(2) << "fullwalk" << sarg1 << dendl;
+          full_walk(sarg1);
+        }
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_REPEATWALK:
+      {
+        string sarg1 = get_sarg(0);
+        if (run_me()) {
+          dout(2) << "repeatwalk " << sarg1 << dendl;
+          while (full_walk(sarg1) == 0) ;
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_RMFILE:
+      {
+        string sarg1 = get_sarg(0);
+        if (run_me()) {
+          rm_file(sarg1);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_WRITEFILE:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        dout(1) << "WRITING SYN CLIENT" << dendl;
+        if (run_me()) {
+          write_file(sarg1, iarg1, iarg2);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_CHUNK:
+      if (run_me()) {
+        string sarg1 = get_sarg(0);
+	chunk_file(sarg1);
+      }
+      did_run_me();
+      break;
+
+
+    case SYNCLIENT_MODE_OVERLOAD_OSD_0:
+      {
+	dout(1) << "OVERLOADING OSD 0" << dendl;
+	int iarg1 = iargs.front(); iargs.pop_front();
+	int iarg2 = iargs.front(); iargs.pop_front();
+	int iarg3 = iargs.front(); iargs.pop_front();
+	if (run_me()) {
+	  overload_osd_0(iarg1, iarg2, iarg3);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_WRSHARED:
+      {
+        string sarg1 = "shared";
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          write_file(sarg1, iarg1, iarg2);
+	}
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_READSHARED:
+      {
+        string sarg1 = "shared";
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          read_file(sarg1, iarg1, iarg2, true);
+	}
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_WRITEBATCH:
+      {
+	int iarg1 = iargs.front(); iargs.pop_front();
+        int iarg2 = iargs.front(); iargs.pop_front();
+        int iarg3 = iargs.front(); iargs.pop_front();
+
+        if (run_me()) {
+          write_batch(iarg1, iarg2, iarg3);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_READFILE:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+
+        dout(1) << "READING SYN CLIENT" << dendl;
+        if (run_me()) {
+          read_file(sarg1, iarg1, iarg2);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_RDWRRANDOM:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+
+        dout(1) << "RANDOM READ WRITE SYN CLIENT" << dendl;
+        if (run_me()) {
+          read_random(sarg1, iarg1, iarg2);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_RDWRRANDOM_EX:
+      {
+        string sarg1 = get_sarg(0);
+        int iarg1 = iargs.front();  iargs.pop_front();
+        int iarg2 = iargs.front();  iargs.pop_front();
+
+        dout(1) << "RANDOM READ WRITE SYN CLIENT" << dendl;
+        if (run_me()) {
+          read_random_ex(sarg1, iarg1, iarg2);
+	}
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_TRACE:
+      {
+        string tfile = get_sarg(0);
+        sargs.push_front(string("~"));
+        int iarg1 = iargs.front();  iargs.pop_front();
+	int playdata = iargs.front(); iargs.pop_front();
+        string prefix = get_sarg(0);
+	char realtfile[100];
+	snprintf(realtfile, sizeof(realtfile), tfile.c_str(), (int)client->get_nodeid().v);
+
+        if (run_me()) {
+          dout(0) << "trace " << tfile << " prefix=" << prefix << " count=" << iarg1 << " data=" << playdata << dendl;
+          
+          Trace t(realtfile);
+          
+	  if (iarg1 == 0) iarg1 = 1; // play trace at least once!
+
+          for (int i=0; i<iarg1; i++) {
+            utime_t start = ceph_clock_now();
+            
+            if (time_to_stop()) break;
+            play_trace(t, prefix, !playdata);
+            if (time_to_stop()) break;
+            if (iarg1 > 1) clean_dir(prefix);  // clean only if repeat
+            
+            utime_t lat = ceph_clock_now();
+            lat -= start;
+            
+            dout(0) << " trace " << tfile << " loop " << (i+1) << "/" << iarg1 << " done in " << (double)lat << " seconds" << dendl;
+            if (client->logger
+                && i > 0
+                && i < iarg1-1
+                ) {
+              //client->logger->finc("trsum", (double)lat);
+              //client->logger->inc("trnum");
+            }
+          }
+	  dout(1) << "done " << dendl;
+        }
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_OPENTEST:
+      {
+        int count = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+          for (int i=0; i<count; i++) {
+            int fd = client->open("test", (rand()%2) ?
+				  (O_WRONLY|O_CREAT) : O_RDONLY,
+				  perms);
+            if (fd > 0) client->close(fd);
+          }
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_OPTEST:
+      {
+        int count = iargs.front();  iargs.pop_front();
+        if (run_me()) {
+	  client->mknod("test", 0777, perms);
+	  struct stat st;
+	  for (int i=0; i<count; i++) {
+	    client->lstat("test", &st, perms);
+	    client->chmod("test", 0777, perms);
+          }
+        }
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_TRUNCATE:
+      {
+        string file = get_sarg(0);
+        sargs.push_front(file);
+        int iarg1 = iargs.front();  iargs.pop_front();
+	if (run_me()) {
+	  client->truncate(file.c_str(), iarg1, perms);
+	}
+	did_run_me();
+      }
+      break;
+
+
+    case SYNCLIENT_MODE_IMPORTFIND:
+      {
+	string base = get_sarg(0);
+	string find = get_sarg(0);
+	int data = get_iarg();
+	if (run_me()) {
+	  import_find(base.c_str(), find.c_str(), data);
+	}
+	did_run_me();
+      }
+      break;
+
+    case SYNCLIENT_MODE_LOOKUPHASH:
+      {
+	inodeno_t ino;
+	string iname = get_sarg(0);
+	sscanf(iname.c_str(), "%llx", (long long unsigned*)&ino.val);
+	inodeno_t dirino;
+	string diname = get_sarg(0);
+	sscanf(diname.c_str(), "%llx", (long long unsigned*)&dirino.val);
+	string name = get_sarg(0);
+	if (run_me()) {
+	  lookup_hash(ino, dirino, name.c_str(), perms);
+	}
+      }
+      break;
+    case SYNCLIENT_MODE_LOOKUPINO:
+      {
+	inodeno_t ino;
+	string iname = get_sarg(0);
+	sscanf(iname.c_str(), "%llx", (long long unsigned*)&ino.val);
+	if (run_me()) {
+	  lookup_ino(ino, perms);
+	}
+      }
+      break;
+      
+    case SYNCLIENT_MODE_MKSNAP:
+      {
+	string base = get_sarg(0);
+	string name = get_sarg(0);
+	if (run_me())
+	  mksnap(base.c_str(), name.c_str(), perms);
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_RMSNAP:
+      {
+	string base = get_sarg(0);
+	string name = get_sarg(0);
+	if (run_me())
+	  rmsnap(base.c_str(), name.c_str(), perms);
+	did_run_me();
+      }
+      break;
+    case SYNCLIENT_MODE_MKSNAPFILE:
+      {
+	string base = get_sarg(0);
+	if (run_me())
+	  mksnapfile(base.c_str());
+	did_run_me();
+      }
+      break;
+
+    default:
+      ceph_abort();
+    }
+  }
+  dout(1) << "syn done, unmounting " << dendl;
+
+  client->unmount();
+  client->shutdown();
+  return 0;
+}
+
+
+int SyntheticClient::start_thread()
+{
+  ceph_assert(!thread_id);
+
+  pthread_create(&thread_id, NULL, synthetic_client_thread_entry, this);
+  ceph_assert(thread_id);
+  ceph_pthread_setname(thread_id, "client");
+  return 0;
+}
+
+int SyntheticClient::join_thread()
+{
+  ceph_assert(thread_id);
+  void *rv;
+  pthread_join(thread_id, &rv);
+  return 0;
+}
+
+
+bool roll_die(float p) 
+{
+  float r = (float)(rand() % 100000) / 100000.0;
+  if (r < p) 
+    return true;
+  else 
+    return false;
+}
+
+void SyntheticClient::init_op_dist()
+{
+  op_dist.clear();
+#if 0
+  op_dist.add( CEPH_MDS_OP_STAT, 610 );
+  op_dist.add( CEPH_MDS_OP_UTIME, 0 );
+  op_dist.add( CEPH_MDS_OP_CHMOD, 1 );
+  op_dist.add( CEPH_MDS_OP_CHOWN, 1 );
+#endif
+
+  op_dist.add( CEPH_MDS_OP_READDIR, 2 );
+  op_dist.add( CEPH_MDS_OP_MKNOD, 30 );
+  op_dist.add( CEPH_MDS_OP_LINK, 0 );
+  op_dist.add( CEPH_MDS_OP_UNLINK, 20 );
+  op_dist.add( CEPH_MDS_OP_RENAME, 40 );
+
+  op_dist.add( CEPH_MDS_OP_MKDIR, 10 );
+  op_dist.add( CEPH_MDS_OP_RMDIR, 20 );
+  op_dist.add( CEPH_MDS_OP_SYMLINK, 20 );
+
+  op_dist.add( CEPH_MDS_OP_OPEN, 200 );
+  //op_dist.add( CEPH_MDS_OP_READ, 0 );
+  //op_dist.add( CEPH_MDS_OP_WRITE, 0 );
+  //op_dist.add( CEPH_MDS_OP_TRUNCATE, 0 );
+  //op_dist.add( CEPH_MDS_OP_FSYNC, 0 );
+  //op_dist.add( CEPH_MDS_OP_RELEASE, 200 );
+  op_dist.normalize();
+}
+
+void SyntheticClient::up()
+{
+  cwd = cwd.prefixpath(cwd.depth()-1);
+  dout(DBL) << "cd .. -> " << cwd << dendl;
+  clear_dir();
+}
+
+int SyntheticClient::play_trace(Trace& t, string& prefix, bool metadata_only)
+{
+  dout(4) << "play trace prefix '" << prefix << "'" << dendl;
+  UserPerm perms = client->pick_my_perms();
+  t.start();
+
+  string buf;
+  string buf2;
+
+  utime_t start = ceph_clock_now();
+
+  ceph::unordered_map<int64_t, int64_t> open_files;
+  ceph::unordered_map<int64_t, dir_result_t*> open_dirs;
+
+  ceph::unordered_map<int64_t, Fh*> ll_files;
+  ceph::unordered_map<int64_t, dir_result_t*> ll_dirs;
+  ceph::unordered_map<uint64_t, int64_t> ll_inos;
+
+  Inode *i1, *i2;
+
+  ll_inos[1] = 1; // root inode is known.
+
+  // prefix?
+  const char *p = prefix.c_str();
+  if (prefix.length()) {
+    client->mkdir(prefix.c_str(), 0755, perms);
+    struct ceph_statx stx;
+    i1 = client->ll_get_inode(vinodeno_t(1, CEPH_NOSNAP));
+    if (client->ll_lookupx(i1, prefix.c_str(), &i2, &stx, CEPH_STATX_INO, 0, perms) == 0) {
+      ll_inos[1] = stx.stx_ino;
+      dout(5) << "'root' ino is " << inodeno_t(stx.stx_ino) << dendl;
+      client->ll_put(i1);
+    } else {
+      dout(0) << "warning: play_trace couldn't lookup up my per-client directory" << dendl;
+    }
+  } else
+    (void) client->ll_get_inode(vinodeno_t(1, CEPH_NOSNAP));
+
+  utime_t last_status = start;
+
+  int n = 0;
+
+  // for object traces
+  ceph::mutex lock = ceph::make_mutex("synclient foo");
+  ceph::condition_variable cond;
+  bool ack;
+
+  while (!t.end()) {
+
+    if (++n == 100) {
+      n = 00;
+      utime_t now = last_status;
+      if (now - last_status > 1.0) {
+	last_status = now;
+	dout(1) << "play_trace at line " << t.get_line() << dendl;
+      }
+    }
+    
+    if (time_to_stop()) break;
+    
+    // op
+    const char *op = t.get_string(buf, 0);
+    dout(4) << (t.get_line()-1) << ": trace op " << op << dendl;
+    
+    if (op[0] == '@') {
+      // timestamp... ignore it!
+      t.get_int(); // sec
+      t.get_int(); // usec
+      op = t.get_string(buf, 0);
+    }
+
+    // high level ops ---------------------
+    UserPerm perms = client->pick_my_perms();
+    if (strcmp(op, "link") == 0) {
+      const char *a = t.get_string(buf, p);
+      const char *b = t.get_string(buf2, p);
+      client->link(a, b, perms);
+    } else if (strcmp(op, "unlink") == 0) {
+      const char *a = t.get_string(buf, p);
+      client->unlink(a, perms);
+    } else if (strcmp(op, "rename") == 0) {
+      const char *a = t.get_string(buf, p);
+      const char *b = t.get_string(buf2, p);
+      client->rename(a,b, perms);
+    } else if (strcmp(op, "mkdir") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      client->mkdir(a, b, perms);
+    } else if (strcmp(op, "rmdir") == 0) {
+      const char *a = t.get_string(buf, p);
+      client->rmdir(a, perms);
+    } else if (strcmp(op, "symlink") == 0) {
+      const char *a = t.get_string(buf, p);
+      const char *b = t.get_string(buf2, p);
+      client->symlink(a, b, perms);
+    } else if (strcmp(op, "readlink") == 0) {
+      const char *a = t.get_string(buf, p);
+      char buf[100];
+      client->readlink(a, buf, 100, perms);
+    } else if (strcmp(op, "lstat") == 0) {
+      struct stat st;
+      const char *a = t.get_string(buf, p);
+      if (strcmp(a, p) != 0 &&
+	  strcmp(a, "/") != 0 &&
+	  strcmp(a, "/lib") != 0 && // or /lib.. that would be a lookup. hack.
+	  a[0] != 0)  // stop stating the root directory already
+	client->lstat(a, &st, perms);
+    } else if (strcmp(op, "chmod") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      client->chmod(a, b, perms);
+    } else if (strcmp(op, "chown") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      int64_t c = t.get_int();
+      client->chown(a, b, c, perms);
+    } else if (strcmp(op, "utime") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      int64_t c = t.get_int();
+      struct utimbuf u;
+      u.actime = b;
+      u.modtime = c;
+      client->utime(a, &u, perms);
+    } else if (strcmp(op, "mknod") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      int64_t c = t.get_int();
+      client->mknod(a, b, perms, c);
+    } else if (strcmp(op, "oldmknod") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      client->mknod(a, b, perms, 0);
+    } else if (strcmp(op, "getdir") == 0) {
+      const char *a = t.get_string(buf, p);
+      list<string> contents;
+      int r = client->getdir(a, contents, perms);
+      if (r < 0) {
+        dout(1) << "getdir on " << a << " returns " << r << dendl;
+      }
+    } else if (strcmp(op, "opendir") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int();
+      dir_result_t *dirp;
+      client->opendir(a, &dirp, perms);
+      if (dirp) open_dirs[b] = dirp;
+    } else if (strcmp(op, "closedir") == 0) {
+      int64_t a = t.get_int();
+      client->closedir(open_dirs[a]);
+      open_dirs.erase(a);
+    } else if (strcmp(op, "open") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int(); 
+      int64_t c = t.get_int(); 
+      int64_t d = t.get_int();
+      int64_t fd = client->open(a, b, perms, c);
+      if (fd > 0) open_files[d] = fd;
+    } else if (strcmp(op, "oldopen") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t b = t.get_int(); 
+      int64_t d = t.get_int();
+      int64_t fd = client->open(a, b, perms, 0755);
+      if (fd > 0) open_files[d] = fd;
+    } else if (strcmp(op, "close") == 0) {
+      int64_t id = t.get_int();
+      int64_t fh = open_files[id];
+      if (fh > 0) client->close(fh);
+      open_files.erase(id);
+    } else if (strcmp(op, "lseek") == 0) {
+      int64_t f = t.get_int();
+      int fd = open_files[f];
+      int64_t off = t.get_int();
+      int64_t whence = t.get_int();
+      client->lseek(fd, off, whence);
+    } else if (strcmp(op, "read") == 0) {
+      int64_t f = t.get_int();
+      int64_t size = t.get_int();
+      int64_t off = t.get_int();
+      int64_t fd = open_files[f];
+      if (!metadata_only) {
+	char *b = new char[size];
+	client->read(fd, b, size, off);
+	delete[] b;
+      }
+    } else if (strcmp(op, "write") == 0) {
+      int64_t f = t.get_int();
+      int64_t fd = open_files[f];
+      int64_t size = t.get_int();
+      int64_t off = t.get_int();
+      if (!metadata_only) {
+	char *b = new char[size];
+	memset(b, 1, size);            // let's write 1's!
+	client->write(fd, b, size, off);
+	delete[] b;
+      } else {
+	client->write(fd, NULL, 0, size+off);
+      }
+    } else if (strcmp(op, "truncate") == 0) {
+      const char *a = t.get_string(buf, p);
+      int64_t l = t.get_int();
+      client->truncate(a, l, perms);
+    } else if (strcmp(op, "ftruncate") == 0) {
+      int64_t f = t.get_int();
+      int fd = open_files[f];
+      int64_t l = t.get_int();
+      client->ftruncate(fd, l, perms);
+    } else if (strcmp(op, "fsync") == 0) {
+      int64_t f = t.get_int();
+      int64_t b = t.get_int();
+      int fd = open_files[f];
+      client->fsync(fd, b);
+    } else if (strcmp(op, "chdir") == 0) {
+      const char *a = t.get_string(buf, p);
+      // Client users should remember their path, but since this
+      // is just a synthetic client we ignore it.
+      std::string ignore;
+      client->chdir(a, ignore, perms);
+    } else if (strcmp(op, "statfs") == 0) {
+      struct statvfs stbuf;
+      client->statfs("/", &stbuf, perms);
+    }
+
+    // low level ops ---------------------
+    else if (strcmp(op, "ll_lookup") == 0) {
+      int64_t i = t.get_int();
+      const char *name = t.get_string(buf, p);
+      int64_t r = t.get_int();
+      struct ceph_statx stx;
+      if (ll_inos.count(i)) {
+	  i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	  if (client->ll_lookupx(i1, name, &i2, &stx, CEPH_STATX_INO, 0, perms) == 0)
+	    ll_inos[r] = stx.stx_ino;
+	  client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_forget") == 0) {
+      int64_t i = t.get_int();
+      int64_t n = t.get_int();
+      if (ll_inos.count(i) && 
+	  client->ll_forget(
+	    client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP)), n))
+	ll_inos.erase(i);
+    } else if (strcmp(op, "ll_getattr") == 0) {
+      int64_t i = t.get_int();
+      struct stat attr;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	client->ll_getattr(i1, &attr, perms);
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_setattr") == 0) {
+      int64_t i = t.get_int();
+      struct stat attr;
+      memset(&attr, 0, sizeof(attr));
+      attr.st_mode = t.get_int();
+      attr.st_uid = t.get_int();
+      attr.st_gid = t.get_int();
+      attr.st_size = t.get_int();
+      attr.st_mtime = t.get_int();
+      attr.st_atime = t.get_int();
+      int mask = t.get_int();
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	client->ll_setattr(i1, &attr, mask, perms);
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_readlink") == 0) {
+      int64_t i = t.get_int();
+      if (ll_inos.count(i)) {
+        char buf[PATH_MAX];
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	client->ll_readlink(i1, buf, sizeof(buf), perms);
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_mknod") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      int m = t.get_int();
+      int r = t.get_int();
+      int64_t ri = t.get_int();
+      struct stat attr;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_mknod(i1, n, m, r, &attr, &i2, perms) == 0)
+	  ll_inos[ri] = attr.st_ino;
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_mkdir") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      int m = t.get_int();
+      int64_t ri = t.get_int();
+      struct stat attr;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_mkdir(i1, n, m, &attr, &i2, perms) == 0)
+	  ll_inos[ri] = attr.st_ino;
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_symlink") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      const char *v = t.get_string(buf2, p);
+      int64_t ri = t.get_int();
+      struct stat attr;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_symlink(i1, n, v, &attr, &i2, perms) == 0)
+	  ll_inos[ri] = attr.st_ino;
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_unlink") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	client->ll_unlink(i1, n, perms);
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_rmdir") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	client->ll_rmdir(i1, n, perms);
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_rename") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      int64_t ni = t.get_int();
+      const char *nn = t.get_string(buf2, p);
+      if (ll_inos.count(i) &&
+	  ll_inos.count(ni)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	i2 = client->ll_get_inode(vinodeno_t(ll_inos[ni],CEPH_NOSNAP));
+	client->ll_rename(i1, n, i2, nn, perms);
+	client->ll_put(i1);
+	client->ll_put(i2);
+      }
+    } else if (strcmp(op, "ll_link") == 0) {
+      int64_t i = t.get_int();
+      int64_t ni = t.get_int();
+      const char *nn = t.get_string(buf, p);
+      if (ll_inos.count(i) &&
+	  ll_inos.count(ni)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	i2 = client->ll_get_inode(vinodeno_t(ll_inos[ni],CEPH_NOSNAP));
+	client->ll_link(i1, i2, nn, perms);
+	client->ll_put(i1);
+	client->ll_put(i2);
+      }
+    } else if (strcmp(op, "ll_opendir") == 0) {
+      int64_t i = t.get_int();
+      int64_t r = t.get_int();
+      dir_result_t *dirp;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_opendir(i1, O_RDONLY, &dirp, perms) == 0)
+	  ll_dirs[r] = dirp;
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_releasedir") == 0) {
+      int64_t f = t.get_int();
+      if (ll_dirs.count(f)) {
+	client->ll_releasedir(ll_dirs[f]);
+	ll_dirs.erase(f);
+      }
+    } else if (strcmp(op, "ll_open") == 0) {
+      int64_t i = t.get_int();
+      int64_t f = t.get_int();
+      int64_t r = t.get_int();
+      Fh *fhp;
+      if (ll_inos.count(i)) {
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_open(i1, f, &fhp, perms) == 0)
+	  ll_files[r] = fhp;
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_create") == 0) {
+      int64_t i = t.get_int();
+      const char *n = t.get_string(buf, p);
+      int64_t m = t.get_int();
+      int64_t f = t.get_int();
+      int64_t r = t.get_int();
+      int64_t ri = t.get_int();
+      struct stat attr;
+      if (ll_inos.count(i)) {
+	Fh *fhp;
+	i1 = client->ll_get_inode(vinodeno_t(ll_inos[i],CEPH_NOSNAP));
+	if (client->ll_create(i1, n, m, f, &attr, NULL, &fhp, perms) == 0) {
+	  ll_inos[ri] = attr.st_ino;
+	  ll_files[r] = fhp;
+	}
+	client->ll_put(i1);
+      }
+    } else if (strcmp(op, "ll_read") == 0) {
+      int64_t f = t.get_int();
+      int64_t off = t.get_int();
+      int64_t size = t.get_int();
+      if (ll_files.count(f) &&
+	  !metadata_only) {
+	bufferlist bl;
+	client->ll_read(ll_files[f], off, size, &bl);
+      }
+    } else if (strcmp(op, "ll_write") == 0) {
+      int64_t f = t.get_int();
+      int64_t off = t.get_int();
+      int64_t size = t.get_int();
+      if (ll_files.count(f)) {
+	if (!metadata_only) {
+	  bufferlist bl;
+	  bufferptr bp(size);
+	  bl.push_back(bp);
+	  bp.zero();
+	  client->ll_write(ll_files[f], off, size, bl.c_str());
+	} else {
+	  client->ll_write(ll_files[f], off+size, 0, NULL);
+	}
+      }
+    } else if (strcmp(op, "ll_flush") == 0) {
+      int64_t f = t.get_int();
+      if (!metadata_only &&
+	  ll_files.count(f)) 
+	client->ll_flush(ll_files[f]);
+    } else if (strcmp(op, "ll_fsync") == 0) {
+      int64_t f = t.get_int();
+      if (!metadata_only &&
+	  ll_files.count(f)) 
+	client->ll_fsync(ll_files[f], false); // FIXME dataonly param
+    } else if (strcmp(op, "ll_release") == 0) {
+      int64_t f = t.get_int();
+      if (ll_files.count(f)) {
+	client->ll_release(ll_files[f]);
+	ll_files.erase(f);
+      }
+    } else if (strcmp(op, "ll_statfs") == 0) {
+      int64_t i = t.get_int();
+      if (ll_inos.count(i))
+	{} //client->ll_statfs(vinodeno_t(ll_inos[i],CEPH_NOSNAP), perms);
+    }
+
+
+    // object-level traces
+
+    else if (strcmp(op, "o_stat") == 0) {
+      int64_t oh = t.get_int();
+      int64_t ol = t.get_int();
+      object_t oid = file_object_t(oh, ol);
+      std::unique_lock locker{lock};
+      object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+      uint64_t size;
+      ceph::real_time mtime;
+      client->objecter->stat(oid, oloc, CEPH_NOSNAP, &size, &mtime, 0,
+			     new C_SafeCond(lock, cond, &ack));
+      cond.wait(locker, [&ack] { return ack; });
+    }
+    else if (strcmp(op, "o_read") == 0) {
+      int64_t oh = t.get_int();
+      int64_t ol = t.get_int();
+      int64_t off = t.get_int();
+      int64_t len = t.get_int();
+      object_t oid = file_object_t(oh, ol);
+      object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+      std::unique_lock locker{lock};
+      bufferlist bl;
+      client->objecter->read(oid, oloc, off, len, CEPH_NOSNAP, &bl, 0,
+			     new C_SafeCond(lock, cond, &ack));
+      cond.wait(locker, [&ack] { return ack; });
+    }
+    else if (strcmp(op, "o_write") == 0) {
+      int64_t oh = t.get_int();
+      int64_t ol = t.get_int();
+      int64_t off = t.get_int();
+      int64_t len = t.get_int();
+      object_t oid = file_object_t(oh, ol);
+      object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+      std::unique_lock locker{lock};
+      bufferptr bp(len);
+      bufferlist bl;
+      bl.push_back(bp);
+      SnapContext snapc;
+      client->objecter->write(oid, oloc, off, len, snapc, bl,
+			      ceph::real_clock::now(), 0,
+			      new C_SafeCond(lock, cond, &ack));
+      cond.wait(locker, [&ack] { return ack; });
+    }
+    else if (strcmp(op, "o_zero") == 0) {
+      int64_t oh = t.get_int();
+      int64_t ol = t.get_int();
+      int64_t off = t.get_int();
+      int64_t len = t.get_int();
+      object_t oid = file_object_t(oh, ol);
+      object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+      std::unique_lock locker{lock};
+      SnapContext snapc;
+      client->objecter->zero(oid, oloc, off, len, snapc,
+			     ceph::real_clock::now(), 0,
+			     new C_SafeCond(lock, cond, &ack));
+      cond.wait(locker, [&ack] { return ack; });
+    }
+
+
+    else {
+      dout(0) << (t.get_line()-1) << ": *** trace hit unrecognized symbol '" << op << "' " << dendl;
+      ceph_abort();
+    }
+  }
+
+  dout(10) << "trace finished on line " << t.get_line() << dendl;
+
+  // close open files
+  for (ceph::unordered_map<int64_t, int64_t>::iterator fi = open_files.begin();
+       fi != open_files.end();
+       ++fi) {
+    dout(1) << "leftover close " << fi->second << dendl;
+    if (fi->second > 0) client->close(fi->second);
+  }
+  for (ceph::unordered_map<int64_t, dir_result_t*>::iterator fi = open_dirs.begin();
+       fi != open_dirs.end();
+       ++fi) {
+    dout(1) << "leftover closedir " << fi->second << dendl;
+    if (fi->second != 0) client->closedir(fi->second);
+  }
+  for (ceph::unordered_map<int64_t,Fh*>::iterator fi = ll_files.begin();
+       fi != ll_files.end();
+       ++fi) {
+    dout(1) << "leftover ll_release " << fi->second << dendl;
+    if (fi->second) client->ll_release(fi->second);
+  }
+  for (ceph::unordered_map<int64_t,dir_result_t*>::iterator fi = ll_dirs.begin();
+       fi != ll_dirs.end();
+       ++fi) {
+    dout(1) << "leftover ll_releasedir " << fi->second << dendl;
+    if (fi->second) client->ll_releasedir(fi->second);
+  }
+  
+  return 0;
+}
+
+
+
+int SyntheticClient::clean_dir(string& basedir)
+{
+  // read dir
+  list<string> contents;
+  UserPerm perms = client->pick_my_perms();
+  int r = client->getdir(basedir.c_str(), contents, perms);
+  if (r < 0) {
+    dout(1) << "getdir on " << basedir << " returns " << r << dendl;
+    return r;
+  }
+
+  for (list<string>::iterator it = contents.begin();
+       it != contents.end();
+       ++it) {
+    if (*it == ".") continue;
+    if (*it == "..") continue;
+    string file = basedir + "/" + *it;
+
+    if (time_to_stop()) break;
+
+    struct stat st;
+    int r = client->lstat(file.c_str(), &st, perms);
+    if (r < 0) {
+      dout(1) << "stat error on " << file << " r=" << r << dendl;
+      continue;
+    }
+
+    if ((st.st_mode & S_IFMT) == S_IFDIR) {
+      clean_dir(file);
+      client->rmdir(file.c_str(), perms);
+    } else {
+      client->unlink(file.c_str(), perms);
+    }
+  }
+
+  return 0;
+
+}
+
+
+int SyntheticClient::full_walk(string& basedir) 
+{
+  if (time_to_stop()) return -1;
+
+  list<string> dirq;
+  list<frag_info_t> statq;
+  dirq.push_back(basedir);
+  frag_info_t empty;
+  statq.push_back(empty);
+
+  ceph::unordered_map<inodeno_t, int> nlink;
+  ceph::unordered_map<inodeno_t, int> nlink_seen;
+
+  UserPerm perms = client->pick_my_perms();
+  while (!dirq.empty()) {
+    string dir = dirq.front();
+    frag_info_t expect = statq.front();
+    dirq.pop_front();
+    statq.pop_front();
+
+    frag_info_t actual = empty;
+
+    // read dir
+    list<string> contents;
+    int r = client->getdir(dir.c_str(), contents, perms);
+    if (r < 0) {
+      dout(1) << "getdir on " << dir << " returns " << r << dendl;
+      continue;
+    }
+    
+    for (list<string>::iterator it = contents.begin();
+	 it != contents.end();
+	 ++it) {
+      if (*it == "." ||
+	  *it == "..") 
+	continue;
+      string file = dir + "/" + *it;
+      
+      struct stat st;
+      frag_info_t dirstat;
+      int r = client->lstat(file.c_str(), &st, perms, &dirstat);
+      if (r < 0) {
+	dout(1) << "stat error on " << file << " r=" << r << dendl;
+	continue;
+      }
+
+      nlink_seen[st.st_ino]++;
+      nlink[st.st_ino] = st.st_nlink;
+
+      if (S_ISDIR(st.st_mode))
+	actual.nsubdirs++;
+      else
+	actual.nfiles++;
+
+      // print
+      char *tm = ctime(&st.st_mtime);
+      tm[strlen(tm)-1] = 0;
+      printf("%llx %c%c%c%c%c%c%c%c%c%c %2d %5d %5d %8llu %12s %s\n",
+	     (long long)st.st_ino,
+	     S_ISDIR(st.st_mode) ? 'd':'-',
+	     (st.st_mode & 0400) ? 'r':'-',
+	     (st.st_mode & 0200) ? 'w':'-',
+	     (st.st_mode & 0100) ? 'x':'-',
+	     (st.st_mode & 040) ? 'r':'-',
+	     (st.st_mode & 020) ? 'w':'-',
+	     (st.st_mode & 010) ? 'x':'-',
+	     (st.st_mode & 04) ? 'r':'-',
+	     (st.st_mode & 02) ? 'w':'-',
+	     (st.st_mode & 01) ? 'x':'-',
+	     (int)st.st_nlink,
+	     (int)st.st_uid, (int)st.st_gid,
+	     (long long unsigned)st.st_size,
+	     tm,
+	     file.c_str());
+
+      
+      if ((st.st_mode & S_IFMT) == S_IFDIR) {
+	dirq.push_back(file);
+	statq.push_back(dirstat);
+      }
+    }
+
+    if (dir != "" &&
+	(actual.nsubdirs != expect.nsubdirs ||
+	 actual.nfiles != expect.nfiles)) {
+      dout(0) << dir << ": expected " << expect << dendl;
+      dout(0) << dir << ":      got " << actual << dendl;
+    }
+  }
+
+  for (ceph::unordered_map<inodeno_t,int>::iterator p = nlink.begin(); p != nlink.end(); ++p) {
+    if (nlink_seen[p->first] != p->second)
+      dout(0) << p->first << " nlink " << p->second << " != " << nlink_seen[p->first] << "seen" << dendl;
+  }
+
+  return 0;
+}
+
+
+
+int SyntheticClient::dump_placement(string& fn) {
+  
+  UserPerm perms = client->pick_my_perms();
+
+  // open file
+  int fd = client->open(fn.c_str(), O_RDONLY, perms);
+  dout(5) << "reading from " << fn << " fd " << fd << dendl;
+  if (fd < 0) return fd;
+
+
+  // How big is it?
+  struct stat stbuf;
+  int lstat_result = client->lstat(fn.c_str(), &stbuf, perms);
+  if (lstat_result < 0) {
+    dout(0) << "lstat error for file " << fn << dendl;
+    client->close(fd);
+    return lstat_result;
+  }
+    
+  off_t filesize = stbuf.st_size;
+ 
+  // grab the placement info
+  vector<ObjectExtent> extents;
+  off_t offset = 0;
+  client->enumerate_layout(fd, extents, filesize, offset);
+  client->close(fd);
+
+
+  // run through all the object extents
+  dout(0) << "file size is " << filesize << dendl;
+  dout(0) << "(osd, start, length) tuples for file " << fn << dendl;
+  for (const auto& x : extents) {
+    int osd = client->objecter->with_osdmap([&](const OSDMap& o) {
+	return o.get_pg_acting_primary(o.object_locator_to_pg(x.oid, x.oloc));
+      });
+
+    // run through all the buffer extents
+    for (const auto& be : x.buffer_extents)
+      dout(0) << "OSD " << osd << ", offset " << be.first
+	      << ", length " << be.second << dendl;
+  }
+  return 0;
+}
+
+
+
+int SyntheticClient::make_dirs(const char *basedir, int dirs, int files, int depth)
+{
+  if (time_to_stop()) return 0;
+
+  UserPerm perms = client->pick_my_perms();
+  // make sure base dir exists
+  int r = client->mkdir(basedir, 0755, perms);
+  if (r != 0) {
+    dout(1) << "can't make base dir? " << basedir << dendl;
+    //return -1;
+  }
+
+  // children
+  char d[500];
+  dout(3) << "make_dirs " << basedir << " dirs " << dirs << " files " << files << " depth " << depth << dendl;
+  for (int i=0; i<files; i++) {
+    snprintf(d, sizeof(d), "%s/file.%d", basedir, i);
+    client->mknod(d, 0644, perms);
+  }
+
+  if (depth == 0) return 0;
+
+  for (int i=0; i<dirs; i++) {
+    snprintf(d, sizeof(d), "%s/dir.%d", basedir, i);
+    make_dirs(d, dirs, files, depth-1);
+  }
+  
+  return 0;
+}
+
+int SyntheticClient::stat_dirs(const char *basedir, int dirs, int files, int depth)
+{
+  if (time_to_stop()) return 0;
+
+  UserPerm perms = client->pick_my_perms();
+
+  // make sure base dir exists
+  struct stat st;
+  int r = client->lstat(basedir, &st, perms);
+  if (r != 0) {
+    dout(1) << "can't make base dir? " << basedir << dendl;
+    return -1;
+  }
+
+  // children
+  char d[500];
+  dout(3) << "stat_dirs " << basedir << " dirs " << dirs << " files " << files << " depth " << depth << dendl;
+  for (int i=0; i<files; i++) {
+    snprintf(d, sizeof(d), "%s/file.%d", basedir, i);
+    client->lstat(d, &st, perms);
+  }
+
+  if (depth == 0) return 0;
+
+  for (int i=0; i<dirs; i++) {
+    snprintf(d, sizeof(d), "%s/dir.%d", basedir, i);
+    stat_dirs(d, dirs, files, depth-1);
+  }
+  
+  return 0;
+}
+int SyntheticClient::read_dirs(const char *basedir, int dirs, int files, int depth)
+{
+  if (time_to_stop()) return 0;
+
+  struct stat st;
+
+  // children
+  char d[500];
+  dout(3) << "read_dirs " << basedir << " dirs " << dirs << " files " << files << " depth " << depth << dendl;
+
+  list<string> contents;
+  UserPerm perms = client->pick_my_perms();
+  utime_t s = ceph_clock_now();
+  int r = client->getdir(basedir, contents, perms);
+  utime_t e = ceph_clock_now();
+  e -= s;
+  if (r < 0) {
+    dout(0) << "getdir couldn't readdir " << basedir << ", stopping" << dendl;
+    return -1;
+  }
+
+  for (int i=0; i<files; i++) {
+    snprintf(d, sizeof(d), "%s/file.%d", basedir, i);
+    utime_t s = ceph_clock_now();
+    if (client->lstat(d, &st, perms) < 0) {
+      dout(2) << "read_dirs failed stat on " << d << ", stopping" << dendl;
+      return -1;
+    }
+    utime_t e = ceph_clock_now();
+    e -= s;
+  }
+
+  if (depth > 0) 
+    for (int i=0; i<dirs; i++) {
+      snprintf(d, sizeof(d), "%s/dir.%d", basedir, i);
+      if (read_dirs(d, dirs, files, depth-1) < 0) return -1;
+    }
+
+  return 0;
+}
+
+
+int SyntheticClient::make_files(int num, int count, int priv, bool more)
+{
+  int whoami = client->get_nodeid().v;
+  char d[255];
+  UserPerm perms = client->pick_my_perms();
+
+  if (priv) {
+    for (int c=0; c<count; c++) {
+      snprintf(d, sizeof(d), "dir.%d.run%d", whoami, c);
+      client->mkdir(d, 0755, perms);
+    }
+  } else {
+    // shared
+    if (true || whoami == 0) {
+      for (int c=0; c<count; c++) {
+        snprintf(d, sizeof(d), "dir.%d.run%d", 0, c);
+        client->mkdir(d, 0755, perms);
+      }
+    } else {
+      sleep(2);
+    }
+  }
+  
+  // files
+  struct stat st;
+  utime_t start = ceph_clock_now();
+  for (int c=0; c<count; c++) {
+    for (int n=0; n<num; n++) {
+      snprintf(d, sizeof(d), "dir.%d.run%d/file.client%d.%d", priv ? whoami:0, c, whoami, n);
+
+      client->mknod(d, 0644, perms);
+
+      if (more) {
+        client->lstat(d, &st, perms);
+        int fd = client->open(d, O_RDONLY, perms);
+        client->unlink(d, perms);
+        client->close(fd);
+      }
+
+      if (time_to_stop()) return 0;
+    }
+  }
+  utime_t end = ceph_clock_now();
+  end -= start;
+  dout(0) << "makefiles time is " << end << " or " << ((double)end / (double)num) <<" per file" << dendl;
+
+  return 0;
+}
+
+int SyntheticClient::link_test()
+{
+  char d[255];
+  char e[255];
+
+  UserPerm perms = client->pick_my_perms();
+
+ // create files
+  int num = 200;
+
+  client->mkdir("orig", 0755, perms);
+  client->mkdir("copy", 0755, perms);
+
+  utime_t start = ceph_clock_now();
+  for (int i=0; i<num; i++) {
+    snprintf(d, sizeof(d), "orig/file.%d", i);
+    client->mknod(d, 0755, perms);
+  }
+  utime_t end = ceph_clock_now();
+  end -= start;
+
+  dout(0) << "orig " << end << dendl;
+
+  // link
+  start = ceph_clock_now();
+  for (int i=0; i<num; i++) {
+    snprintf(d, sizeof(d), "orig/file.%d", i);
+    snprintf(e, sizeof(e), "copy/file.%d", i);
+    client->link(d, e, perms);
+  }
+  end = ceph_clock_now();
+  end -= start;
+  dout(0) << "copy " << end << dendl;
+
+  return 0;
+}
+
+
+int SyntheticClient::create_shared(int num)
+{
+  // files
+  UserPerm perms = client->pick_my_perms();
+  char d[255];
+  client->mkdir("test", 0755, perms);
+  for (int n=0; n<num; n++) {
+    snprintf(d, sizeof(d), "test/file.%d", n);
+    client->mknod(d, 0644, perms);
+  }
+  
+  return 0;
+}
+
+int SyntheticClient::open_shared(int num, int count)
+{
+  // files
+  char d[255];
+  UserPerm perms = client->pick_my_perms();
+  for (int c=0; c<count; c++) {
+    // open
+    list<int> fds;
+    for (int n=0; n<num; n++) {
+      snprintf(d, sizeof(d), "test/file.%d", n);
+      int fd = client->open(d, O_RDONLY, perms);
+      if (fd > 0) fds.push_back(fd);
+    }
+
+    if (false && client->get_nodeid() == 0)
+      for (int n=0; n<num; n++) {
+	snprintf(d, sizeof(d), "test/file.%d", n);
+	client->unlink(d, perms);
+      }
+
+    while (!fds.empty()) {
+      int fd = fds.front();
+      fds.pop_front();
+      client->close(fd);
+    }
+  }
+  
+  return 0;
+}
+
+
+// Hits OSD 0 with writes to various files with OSD 0 as the primary.
+int SyntheticClient::overload_osd_0(int n, int size, int wrsize) {
+  UserPerm perms = client->pick_my_perms();
+  // collect a bunch of files starting on OSD 0
+  int left = n;
+  int tried = 0;
+  while (left < 0) {
+
+
+    // pull open a file
+    dout(0) << "in OSD overload" << dendl;
+    string filename = get_sarg(tried);
+    dout(1) << "OSD Overload workload: trying file " << filename << dendl;
+    int fd = client->open(filename.c_str(), O_RDWR|O_CREAT, perms);
+    ++tried;
+
+    // only use the file if its first primary is OSD 0
+    int primary_osd = check_first_primary(fd);
+    if (primary_osd != 0) {
+      client->close(fd);
+      dout(1) << "OSD Overload workload: SKIPPING file " << filename <<
+	" with OSD " << primary_osd << " as first primary. " << dendl;
+      continue;
+    }
+      dout(1) << "OSD Overload workload: USING file " << filename <<
+	" with OSD 0 as first primary. " << dendl;
+
+
+    --left;
+    // do whatever operation we want to do on the file. How about a write?
+    write_fd(fd, size, wrsize);
+  }
+  return 0;
+}
+
+
+// See what the primary is for the first object in this file.
+int SyntheticClient::check_first_primary(int fh)
+{
+  vector<ObjectExtent> extents;
+  client->enumerate_layout(fh, extents, 1, 0);
+  return client->objecter->with_osdmap([&](const OSDMap& o) {
+      return o.get_pg_acting_primary(
+	o.object_locator_to_pg(extents.begin()->oid, extents.begin()->oloc));
+    });
+}
+
+int SyntheticClient::rm_file(string& fn)
+{
+  UserPerm perms = client->pick_my_perms();
+  return client->unlink(fn.c_str(), perms);
+}
+
+int SyntheticClient::write_file(string& fn, int size, loff_t wrsize)   // size is in MB, wrsize in bytes
+{
+  //uint64_t wrsize = 1024*256;
+  char *buf = new char[wrsize+100];   // 1 MB
+  memset(buf, 7, wrsize);
+  int64_t chunks = (uint64_t)size * (uint64_t)(1024*1024) / (uint64_t)wrsize;
+  UserPerm perms = client->pick_my_perms();
+
+  int fd = client->open(fn.c_str(), O_RDWR|O_CREAT, perms);
+  dout(5) << "writing to " << fn << " fd " << fd << dendl;
+  if (fd < 0) {
+    delete[] buf;
+    return fd;
+  }
+
+  utime_t from = ceph_clock_now();
+  utime_t start = from;
+  uint64_t bytes = 0, total = 0;
+
+
+  for (loff_t i=0; i<chunks; i++) {
+    if (time_to_stop()) {
+      dout(0) << "stopping" << dendl;
+      break;
+    }
+    dout(2) << "writing block " << i << "/" << chunks << dendl;
+    
+    // fill buf with a 16 byte fingerprint
+    // 64 bits : file offset
+    // 64 bits : client id
+    // = 128 bits (16 bytes)
+    uint64_t *p = (uint64_t*)buf;
+    while ((char*)p < buf + wrsize) {
+      *p = (uint64_t)i*(uint64_t)wrsize + (uint64_t)((char*)p - buf);      
+      p++;
+      *p = client->get_nodeid().v;
+      p++;
+    }
+
+    client->write(fd, buf, wrsize, i*wrsize);
+    bytes += wrsize;
+    total += wrsize;
+
+    utime_t now = ceph_clock_now();
+    if (now - from >= 1.0) {
+      double el = now - from;
+      dout(0) << "write " << (bytes / el / 1048576.0) << " MB/sec" << dendl;
+      from = now;
+      bytes = 0;
+    }
+  }
+
+  client->fsync(fd, true);
+
+  utime_t stop = ceph_clock_now();
+  double el = stop - start;
+  dout(0) << "write total " << (total / el / 1048576.0) << " MB/sec ("
+	  << total << " bytes in " << el << " seconds)" << dendl;
+
+  client->close(fd);
+  delete[] buf;
+
+  return 0;
+}
+
+int SyntheticClient::write_fd(int fd, int size, int wrsize)   // size is in MB, wrsize in bytes
+{
+  //uint64_t wrsize = 1024*256;
+  char *buf = new char[wrsize+100];   // 1 MB
+  memset(buf, 7, wrsize);
+  uint64_t chunks = (uint64_t)size * (uint64_t)(1024*1024) / (uint64_t)wrsize;
+
+  //dout(5) << "SyntheticClient::write_fd: writing to fd " << fd << dendl;
+  if (fd < 0) {
+    delete[] buf;
+    return fd;
+  }
+
+  for (unsigned i=0; i<chunks; i++) {
+    if (time_to_stop()) {
+      dout(0) << "stopping" << dendl;
+      break;
+    }
+    dout(2) << "writing block " << i << "/" << chunks << dendl;
+    
+    // fill buf with a 16 byte fingerprint
+    // 64 bits : file offset
+    // 64 bits : client id
+    // = 128 bits (16 bytes)
+    uint64_t *p = (uint64_t*)buf;
+    while ((char*)p < buf + wrsize) {
+      *p = (uint64_t)i*(uint64_t)wrsize + (uint64_t)((char*)p - buf);      
+      p++;
+      *p = client->get_nodeid().v;
+      p++;
+    }
+
+    client->write(fd, buf, wrsize, i*wrsize);
+  }
+  client->close(fd);
+  delete[] buf;
+
+  return 0;
+}
+
+
+int SyntheticClient::write_batch(int nfile, int size, int wrsize)
+{
+  for (int i=0; i<nfile; i++) {
+      string sarg1 = get_sarg(i);
+    dout(0) << "Write file " << sarg1 << dendl;
+    write_file(sarg1, size, wrsize);
+  }
+  return 0;
+}
+
+// size is in MB, wrsize in bytes
+int SyntheticClient::read_file(const std::string& fn, int size,
+			       int rdsize, bool ignoreprint)
+{
+  char *buf = new char[rdsize]; 
+  memset(buf, 1, rdsize);
+  uint64_t chunks = (uint64_t)size * (uint64_t)(1024*1024) / (uint64_t)rdsize;
+  UserPerm perms = client->pick_my_perms();
+
+  int fd = client->open(fn.c_str(), O_RDONLY, perms);
+  dout(5) << "reading from " << fn << " fd " << fd << dendl;
+  if (fd < 0) {
+    delete[] buf;
+    return fd;
+  }
+
+  utime_t from = ceph_clock_now();
+  utime_t start = from;
+  uint64_t bytes = 0, total = 0;
+
+  for (unsigned i=0; i<chunks; i++) {
+    if (time_to_stop()) break;
+    dout(2) << "reading block " << i << "/" << chunks << dendl;
+    int r = client->read(fd, buf, rdsize, i*rdsize);
+    if (r < rdsize) {
+      dout(1) << "read_file got r = " << r << ", probably end of file" << dendl;
+      break;
+    }
+ 
+    bytes += rdsize;
+    total += rdsize;
+
+    utime_t now = ceph_clock_now();
+    if (now - from >= 1.0) {
+      double el = now - from;
+      dout(0) << "read " << (bytes / el / 1048576.0) << " MB/sec" << dendl;
+      from = now;
+      bytes = 0;
+    }
+
+    // verify fingerprint
+    int bad = 0;
+    uint64_t *p = (uint64_t*)buf;
+    while ((char*)p + 32 < buf + rdsize) {
+      uint64_t readoff = *p;
+      uint64_t wantoff = (uint64_t)i*(uint64_t)rdsize + (uint64_t)((char*)p - buf);
+      p++;
+      int64_t readclient = *p;
+      p++;
+      if (readoff != wantoff ||
+	  readclient != client->get_nodeid()) {
+        if (!bad && !ignoreprint)
+          dout(0) << "WARNING: wrong data from OSD, block says fileoffset=" << readoff << " client=" << readclient
+		  << ", should be offset " << wantoff << " client " << client->get_nodeid()
+		  << dendl;
+        bad++;
+      }
+    }
+    if (bad && !ignoreprint) 
+      dout(0) << " + " << (bad-1) << " other bad 16-byte bits in this block" << dendl;
+  }
+
+  utime_t stop = ceph_clock_now();
+  double el = stop - start;
+  dout(0) << "read total " << (total / el / 1048576.0) << " MB/sec ("
+	  << total << " bytes in " << el << " seconds)" << dendl;
+
+  client->close(fd);
+  delete[] buf;
+
+  return 0;
+}
+
+
+
+
+class C_Ref : public Context {
+  ceph::mutex& lock;
+  ceph::condition_variable& cond;
+  int *ref;
+public:
+  C_Ref(ceph::mutex &l, ceph::condition_variable &c, int *r)
+    : lock(l), cond(c), ref(r) {
+    lock_guard locker{lock};
+    (*ref)++;
+  }
+  void finish(int) override {
+    lock_guard locker{lock};
+    (*ref)--;
+    cond.notify_all();
+  }
+};
+
+int SyntheticClient::create_objects(int nobj, int osize, int inflight)
+{
+  // divy up
+  int numc = num_client ? num_client : 1;
+
+  int start, inc, end;
+
+  if (1) {
+    // strided
+    start = client->get_nodeid().v; //nobjs % numc;
+    inc = numc;
+    end = start + nobj;
+  } else {
+    // segments
+    start = nobj * client->get_nodeid().v / numc;
+    inc = 1;
+    end = nobj * (client->get_nodeid().v+1) / numc;
+  }
+
+  dout(5) << "create_objects " << nobj << " size=" << osize 
+	  << " .. doing [" << start << "," << end << ") inc " << inc
+	  << dendl;
+  
+  bufferptr bp(osize);
+  bp.zero();
+  bufferlist bl;
+  bl.push_back(bp);
+
+  ceph::mutex lock = ceph::make_mutex("create_objects lock");
+  ceph::condition_variable cond;
+  
+  int unsafe = 0;
+  
+  list<utime_t> starts;
+
+  for (int i=start; i<end; i += inc) {
+    if (time_to_stop()) break;
+
+    object_t oid = file_object_t(999, i);
+    object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+    SnapContext snapc;
+    
+    if (i % inflight == 0) {
+      dout(6) << "create_objects " << i << "/" << (nobj+1) << dendl;
+    }
+    dout(10) << "writing " << oid << dendl;
+
+    starts.push_back(ceph_clock_now());
+    {
+      std::lock_guard locker{client->client_lock};
+      client->objecter->write(oid, oloc, 0, osize, snapc, bl,
+			      ceph::real_clock::now(), 0,
+			      new C_Ref(lock, cond, &unsafe));
+    }
+    {
+      std::unique_lock locker{lock};
+      cond.wait(locker, [&unsafe, inflight, this] {
+        if (unsafe > inflight) {
+	  dout(20) << "waiting for " << unsafe << " unsafe" << dendl;
+	}
+	return unsafe <= inflight;
+      });
+    }
+    utime_t lat = ceph_clock_now();
+    lat -= starts.front();
+    starts.pop_front();
+  }
+  {
+    std::unique_lock locker{lock};
+    cond.wait(locker, [&unsafe, this] {
+      if (unsafe > 0) {
+	dout(10) << "waiting for " << unsafe << " unsafe" << dendl;
+      }
+      return unsafe <= 0;
+    });
+  }
+  dout(5) << "create_objects done" << dendl;
+  return 0;
+}
+
+int SyntheticClient::object_rw(int nobj, int osize, int wrpc, 
+			       int overlappc,
+			       double rskew, double wskew)
+{
+  dout(5) << "object_rw " << nobj << " size=" << osize << " with "
+	  << wrpc << "% writes" 
+	  << ", " << overlappc << "% overlap"
+	  << ", rskew = " << rskew
+	  << ", wskew = " << wskew
+	  << dendl;
+
+  bufferptr bp(osize);
+  bp.zero();
+  bufferlist bl;
+  bl.push_back(bp);
+
+  // start with odd number > nobj
+  rjhash<uint32_t> h;
+  unsigned prime = nobj + 1;             // this is the minimum!
+  prime += h(nobj) % (3*nobj);  // bump it up some
+  prime |= 1;                               // make it odd
+
+  while (true) {
+    unsigned j;
+    for (j=2; j*j<=prime; j++)
+      if (prime % j == 0) break;
+    if (j*j > prime) {
+      break;
+      //cout << "prime " << prime << endl;
+    }
+    prime += 2;
+  }
+
+  ceph::mutex lock = ceph::make_mutex("lock");
+  ceph::condition_variable cond;
+
+  int unack = 0;
+
+  while (1) {
+    if (time_to_stop()) break;
+    
+    // read or write?
+    bool write = (rand() % 100) < wrpc;
+
+    // choose object
+    double r = drand48(); // [0..1)
+    long o;
+    if (write) {
+      o = (long)trunc(pow(r, wskew) * (double)nobj);  // exponentially skew towards 0
+      int pnoremap = (long)(r * 100.0);
+      if (pnoremap >= overlappc) 
+	o = (o*prime) % nobj;    // remap
+    } else {
+      o = (long)trunc(pow(r, rskew) * (double)nobj);  // exponentially skew towards 0
+    }
+    object_t oid = file_object_t(999, o);
+    object_locator_t oloc(SYNCLIENT_FIRST_POOL);
+    SnapContext snapc;
+    
+    client->client_lock.lock();
+    utime_t start = ceph_clock_now();
+    if (write) {
+      dout(10) << "write to " << oid << dendl;
+
+      ObjectOperation m;
+      OSDOp op;
+      op.op.op = CEPH_OSD_OP_WRITE;
+      op.op.extent.offset = 0;
+      op.op.extent.length = osize;
+      op.indata = bl;
+      m.ops.push_back(op);
+      client->objecter->mutate(oid, oloc, m, snapc,
+			       ceph::real_clock::now(), 0,
+			       new C_Ref(lock, cond, &unack));
+    } else {
+      dout(10) << "read from " << oid << dendl;
+      bufferlist inbl;
+      client->objecter->read(oid, oloc, 0, osize, CEPH_NOSNAP, &inbl, 0,
+			     new C_Ref(lock, cond, &unack));
+    }
+    client->client_lock.unlock();
+
+    {
+      std::unique_lock locker{lock};
+      cond.wait(locker, [&unack, this] {
+	if (unack > 0) {
+	  dout(20) << "waiting for " << unack << " unack" << dendl;
+	}
+	return unack <= 0;
+      });
+    }
+
+    utime_t lat = ceph_clock_now();
+    lat -= start;
+  }
+
+  return 0;
+}
+
+
+
+
+
+int SyntheticClient::read_random(string& fn, int size, int rdsize)   // size is in MB, wrsize in bytes
+{
+  UserPerm perms = client->pick_my_perms();
+  uint64_t chunks = (uint64_t)size * (uint64_t)(1024*1024) / (uint64_t)rdsize;
+  int fd = client->open(fn.c_str(), O_RDWR, perms);
+  dout(5) << "reading from " << fn << " fd " << fd << dendl;
+
+  if (fd < 0) return fd;
+  int offset = 0;
+  char * buf = NULL;
+
+  for (unsigned i=0; i<2000; i++) {
+    if (time_to_stop()) break;
+
+    bool read=false;
+
+    time_t seconds;
+    time( &seconds);
+    srand(seconds);
+
+    // use rand instead ??
+    double x = drand48();
+
+    // cleanup before call 'new'
+    if (buf != NULL) {
+	delete[] buf;
+	buf = NULL;
+    }
+    if (x < 0.5) {
+        buf = new char[rdsize]; 
+        memset(buf, 1, rdsize);
+        read=true;
+    } else {
+        buf = new char[rdsize+100];   // 1 MB
+        memset(buf, 7, rdsize);
+    }
+    
+    if (read) {
+        offset=(rand())%(chunks+1);
+        dout(2) << "reading block " << offset << "/" << chunks << dendl;
+
+        int r = client->read(fd, buf, rdsize, offset*rdsize);
+        if (r < rdsize) {
+	  dout(1) << "read_file got r = " << r << ", probably end of file" << dendl;
+	}
+    } else {
+      dout(2) << "writing block " << offset << "/" << chunks << dendl;
+
+      // fill buf with a 16 byte fingerprint
+      // 64 bits : file offset
+      // 64 bits : client id
+      // = 128 bits (16 bytes)
+
+      offset=(rand())%(chunks+1);
+      uint64_t *p = (uint64_t*)buf;
+      while ((char*)p < buf + rdsize) {
+	*p = offset*rdsize + (char*)p - buf;      
+	p++;
+	*p = client->get_nodeid().v;
+	p++;
+      }
+
+      client->write(fd, buf, rdsize,
+                        offset*rdsize);
+    }
+
+    // verify fingerprint
+    if (read) {
+      int bad = 0;
+      int64_t *p = (int64_t*)buf;
+      while ((char*)p + 32 < buf + rdsize) {
+	int64_t readoff = *p;
+	int64_t wantoff = offset*rdsize + (int64_t)((char*)p - buf);
+	p++;
+	int64_t readclient = *p;
+	p++;
+	if (readoff != wantoff || readclient != client->get_nodeid()) {
+	  if (!bad)
+	    dout(0) << "WARNING: wrong data from OSD, block says fileoffset=" << readoff << " client=" << readclient
+		    << ", should be offset " << wantoff << " client " << client->get_nodeid()
+		    << dendl;
+	  bad++;
+	}
+      }
+      if (bad) 
+	dout(0) << " + " << (bad-1) << " other bad 16-byte bits in this block" << dendl;
+    }
+  }
+  
+  client->close(fd);
+  delete[] buf;
+
+  return 0;
+}
+
+int normdist(int min, int max, int stdev) /* specifies input values */
+{
+  /* min: Minimum value; max: Maximum value; stdev: degree of deviation */
+  
+  //int min, max, stdev; {
+  time_t seconds;
+  time( &seconds);
+  srand(seconds);
+  
+  int range, iterate, result;
+  /* declare range, iterate and result as integers, to avoid the need for
+     floating point math*/
+  
+  result = 0;
+  /* ensure result is initialized to 0 */
+  
+  range = max -min;
+  /* calculate range of possible values between the max and min values */
+  
+  iterate = range / stdev;
+  /* this number of iterations ensures the proper shape of the resulting
+     curve */
+  
+  stdev += 1; /* compensation for integer vs. floating point math */
+  for (int c = iterate; c != 0; c--) /* loop through iterations */
+    {
+      //  result += (uniform (1, 100) * stdev) / 100; /* calculate and
+      result += ( (rand()%100 + 1)  * stdev) / 100;
+      // printf("result=%d\n", result );
+    }
+  printf("\n final result=%d\n", result );
+  return result + min; /* send final result back */
+}
+
+int SyntheticClient::read_random_ex(string& fn, int size, int rdsize)   // size is in MB, wrsize in bytes
+{
+  uint64_t chunks = (uint64_t)size * (uint64_t)(1024*1024) / (uint64_t)rdsize;
+  UserPerm perms = client->pick_my_perms();
+  int fd = client->open(fn.c_str(), O_RDWR, perms);
+  dout(5) << "reading from " << fn << " fd " << fd << dendl;
+  
+  if (fd < 0) return fd;
+  int offset = 0;
+  char * buf = NULL;
+  
+  for (unsigned i=0; i<2000; i++) {
+    if (time_to_stop()) break;
+    
+    bool read=false;
+    
+    time_t seconds;
+    time( &seconds);
+    srand(seconds);
+    
+    // use rand instead ??
+    double x = drand48();
+    
+    // cleanup before call 'new'
+    if (buf != NULL) {
+      delete[] buf;
+      buf = NULL;
+    }
+    if (x < 0.5) {
+      buf = new char[rdsize]; 
+      memset(buf, 1, rdsize);
+      read=true;
+    } else {
+      buf = new char[rdsize+100];   // 1 MB
+      memset(buf, 7, rdsize);
+    }
+    
+    if (read) {
+      dout(2) << "reading block " << offset << "/" << chunks << dendl;
+	
+      int r = client->read(fd, buf, rdsize,
+			     offset*rdsize);
+      if (r < rdsize) {
+	dout(1) << "read_file got r = " << r << ", probably end of file" << dendl;
+      }
+    } else {
+        dout(2) << "writing block " << offset << "/" << chunks << dendl;
+	
+	// fill buf with a 16 byte fingerprint
+	// 64 bits : file offset
+	// 64 bits : client id
+	// = 128 bits (16 bytes)
+	
+	int count = rand()%10;
+	
+	for ( int j=0;j<count; j++ ) {
+	  offset=(rand())%(chunks+1);
+	  uint64_t *p = (uint64_t*)buf;
+	  while ((char*)p < buf + rdsize) {
+	    *p = offset*rdsize + (char*)p - buf;      
+	    p++;
+	    *p = client->get_nodeid().v;
+	    p++;
+	  }
+	    
+	  client->write(fd, buf, rdsize, offset*rdsize);
+	}
+    }
+    
+    // verify fingerprint
+    if (read) {
+      int bad = 0;
+      int64_t *p = (int64_t*)buf;
+      while ((char*)p + 32 < buf + rdsize) {
+	int64_t readoff = *p;
+	int64_t wantoff = offset*rdsize + (int64_t)((char*)p - buf);
+	p++;
+	int64_t readclient = *p;
+	p++;
+	if (readoff != wantoff || readclient != client->get_nodeid()) { 
+	  if (!bad)
+	    dout(0) << "WARNING: wrong data from OSD, block says fileoffset=" << readoff << " client=" << readclient
+		    << ", should be offset " << wantoff << " client " << client->get_nodeid()
+		    << dendl;
+	  bad++;
+	}
+      }
+      if (bad) 
+	dout(0) << " + " << (bad-1) << " other bad 16-byte bits in this block" << dendl;
+    }
+  }
+  
+  client->close(fd);
+  delete[] buf;
+
+  return 0;
+}
+
+
+int SyntheticClient::random_walk(int num_req)
+{
+  int left = num_req;
+
+  //dout(1) << "random_walk() will do " << left << " ops" << dendl;
+
+  init_op_dist();  // set up metadata op distribution
+ 
+  UserPerm perms = client->pick_my_perms();
+  while (left > 0) {
+    left--;
+
+    if (time_to_stop()) break;
+
+    // ascend?
+    if (cwd.depth() && !roll_die(::pow((double).9, (double)cwd.depth()))) {
+      dout(DBL) << "die says up" << dendl;
+      up();
+      continue;
+    }
+
+    // descend?
+    if (roll_die(::pow((double).9,(double)cwd.depth())) && !subdirs.empty()) {
+      string s = get_random_subdir();
+      cwd.push_dentry( s );
+      dout(DBL) << "cd " << s << " -> " << cwd << dendl;
+      clear_dir();
+      continue;
+    }
+
+    int op = 0;
+    filepath path;
+
+    if (contents.empty() && roll_die(.3)) {
+      if (did_readdir) {
+        dout(DBL) << "empty dir, up" << dendl;
+        up();
+      } else
+        op = CEPH_MDS_OP_READDIR;
+    } else {
+      op = op_dist.sample();
+    }
+    //dout(DBL) << "op is " << op << dendl;
+
+    int r = 0;
+
+    // do op
+    if (op == CEPH_MDS_OP_UNLINK) {
+      if (contents.empty())
+        op = CEPH_MDS_OP_READDIR;
+      else 
+        r = client->unlink(get_random_sub(), perms);   // will fail on dirs
+    }
+     
+    if (op == CEPH_MDS_OP_RENAME) {
+      if (contents.empty())
+        op = CEPH_MDS_OP_READDIR;
+      else {
+        r = client->rename(get_random_sub(), make_sub("ren"), perms);
+      }
+    }
+    
+    if (op == CEPH_MDS_OP_MKDIR) {
+      r = client->mkdir(make_sub("mkdir"), 0755, perms);
+    }
+    
+    if (op == CEPH_MDS_OP_RMDIR) {
+      if (!subdirs.empty())
+        r = client->rmdir(get_random_subdir(), perms);
+      else
+        r = client->rmdir(cwd.c_str(), perms);     // will pbly fail
+    }
+    
+    if (op == CEPH_MDS_OP_SYMLINK) {
+    }
+    /*
+    if (op == CEPH_MDS_OP_CHMOD) {
+      if (contents.empty())
+        op = CEPH_MDS_OP_READDIR;
+      else
+        r = client->chmod(get_random_sub(), rand() & 0755, perms);
+    }
+    
+    if (op == CEPH_MDS_OP_CHOWN) {
+      if (contents.empty())         r = client->chown(cwd.c_str(), rand(), rand(), perms);
+      else
+        r = client->chown(get_random_sub(), rand(), rand(), perms);
+    }
+     
+    if (op == CEPH_MDS_OP_UTIME) {
+      struct utimbuf b;
+      memset(&b, 1, sizeof(b));
+      if (contents.empty()) 
+        r = client->utime(cwd.c_str(), &b, perms);
+      else
+        r = client->utime(get_random_sub(), &b, perms);
+    }
+    */
+    if (op == CEPH_MDS_OP_LINK) {
+    }
+    
+    if (op == CEPH_MDS_OP_MKNOD) {
+      r = client->mknod(make_sub("mknod"), 0644, perms);
+    }
+     
+    if (op == CEPH_MDS_OP_OPEN) {
+      if (contents.empty())
+        op = CEPH_MDS_OP_READDIR;
+      else {
+        r = client->open(get_random_sub(), O_RDONLY, perms);
+        if (r > 0) {
+          ceph_assert(open_files.count(r) == 0);
+          open_files.insert(r);
+        }
+      }
+    }
+
+    /*if (op == CEPH_MDS_OP_RELEASE) {   // actually, close
+      if (open_files.empty())
+        op = CEPH_MDS_OP_STAT;
+      else {
+        int fh = get_random_fh();
+        r = client->close( fh );
+        if (r == 0) open_files.erase(fh);
+      }
+    }
+    */
+    
+    if (op == CEPH_MDS_OP_GETATTR) {
+      struct stat st;
+      if (contents.empty()) {
+        if (did_readdir) {
+          if (roll_die(.1)) {
+            dout(DBL) << "stat in empty dir, up" << dendl;
+            up();
+          } else {
+            op = CEPH_MDS_OP_MKNOD;
+          }
+        } else
+          op = CEPH_MDS_OP_READDIR;
+      } else
+        r = client->lstat(get_random_sub(), &st, perms);
+    }
+
+    if (op == CEPH_MDS_OP_READDIR) {
+      clear_dir();
+      
+      list<string> c;
+      r = client->getdir(cwd.c_str(), c, perms);
+      
+      for (list<string>::iterator it = c.begin();
+           it != c.end();
+           ++it) {
+        //dout(DBL) << " got " << *it << dendl;
+	ceph_abort();
+	/*contents[*it] = it->second;
+        if (it->second &&
+	    S_ISDIR(it->second->st_mode)) 
+          subdirs.insert(*it);
+	*/
+      }
+      
+      did_readdir = true;
+    }
+      
+    // errors?
+    if (r < 0) {
+      // reevaluate cwd.
+      //while (cwd.depth()) {
+      //if (client->lookup(cwd)) break;   // it's in the cache
+        
+      //dout(DBL) << "r = " << r << ", client doesn't have " << cwd << ", cd .." << dendl;
+      dout(DBL) << "r = " << r << ", client may not have " << cwd << ", cd .." << dendl;
+      up();
+      //}      
+    }
+  }
+
+  // close files
+  dout(DBL) << "closing files" << dendl;
+  while (!open_files.empty()) {
+    int fh = get_random_fh();
+    int r = client->close( fh );
+    if (r == 0) open_files.erase(fh);
+  }
+
+  dout(DBL) << "done" << dendl;
+  return 0;
+}
+
+
+
+
+void SyntheticClient::make_dir_mess(const char *basedir, int n)
+{
+  UserPerm perms = client->pick_my_perms();
+  vector<string> dirs;
+  
+  dirs.push_back(basedir);
+  dirs.push_back(basedir);
+  
+  client->mkdir(basedir, 0755, perms);
+
+  // motivation:
+  //  P(dir) ~ subdirs_of(dir) + 2
+  // from 5-year metadata workload paper in fast'07
+
+  // create dirs
+  for (int i=0; i<n; i++) {
+    // pick a dir
+    int k = rand() % dirs.size();
+    string parent = dirs[k];
+    
+    // pick a name
+    std::stringstream ss;
+    ss << parent << "/" << i;
+    string dir = ss.str();
+
+    // update dirs
+    dirs.push_back(parent);
+    dirs.push_back(dir);
+    dirs.push_back(dir);
+
+    // do it
+    client->mkdir(dir.c_str(), 0755, perms);
+  }
+    
+  
+}
+
+
+
+void SyntheticClient::foo()
+{
+  UserPerm perms = client->pick_my_perms();
+
+  if (1) {
+    // make 2 parallel dirs, link/unlink between them.
+    char a[100], b[100];
+    client->mkdir("/a", 0755, perms);
+    client->mkdir("/b", 0755, perms);
+    for (int i=0; i<10; i++) {
+      snprintf(a, sizeof(a), "/a/%d", i);
+      client->mknod(a, 0644, perms);
+    }
+    while (1) {
+      for (int i=0; i<10; i++) {
+	snprintf(a, sizeof(a), "/a/%d", i);
+	snprintf(b, sizeof(b), "/b/%d", i);
+	client->link(a, b, perms);
+      }
+      for (int i=0; i<10; i++) {
+	snprintf(b, sizeof(b), "/b/%d", i);
+	client->unlink(b, perms);
+      }
+    }
+    return;
+  }
+  if (1) {
+    // bug1.cpp
+    const char *fn = "blah";
+    char buffer[8192]; 
+    client->unlink(fn, perms);
+    int handle = client->open(fn, O_CREAT|O_RDWR, perms, S_IRWXU);
+    ceph_assert(handle>=0);
+    int r=client->write(handle,buffer,8192);
+    ceph_assert(r>=0);
+    r=client->close(handle);
+    ceph_assert(r>=0);
+         
+    handle = client->open(fn, O_RDWR, perms); // open the same  file, it must have some data already
+    ceph_assert(handle>=0);      
+    r=client->read(handle,buffer,8192);
+    ceph_assert(r==8192); //  THIS ASSERTION FAILS with disabled cache
+    r=client->close(handle);
+    ceph_assert(r>=0);
+
+    return;
+  }
+  if (1) {
+    dout(0) << "first" << dendl;
+    int fd = client->open("tester", O_WRONLY|O_CREAT, perms);
+    client->write(fd, "hi there", 0, 8);
+    client->close(fd);
+    dout(0) << "sleep" << dendl;
+    sleep(10);
+    dout(0) << "again" << dendl;
+    fd = client->open("tester", O_WRONLY|O_CREAT, perms);
+    client->write(fd, "hi there", 0, 8);
+    client->close(fd);
+    return;    
+  }
+  if (1) {
+    // open some files
+    srand(0);
+    for (int i=0; i<20; i++) {
+      int s = 5;
+      int a = rand() % s;
+      int b = rand() % s;
+      int c = rand() % s;
+      char src[80];
+      snprintf(src, sizeof(src), "syn.0.0/dir.%d/dir.%d/file.%d", a, b, c);
+      //int fd = 
+      client->open(src, O_RDONLY, perms);
+    }
+
+    return;
+  }
+
+  if (0) {
+    // rename fun
+    for (int i=0; i<100; i++) {
+      int s = 5;
+      int a = rand() % s;
+      int b = rand() % s;
+      int c = rand() % s;
+      int d = rand() % s;
+      int e = rand() % s;
+      int f = rand() % s;
+      char src[80];
+      char dst[80];
+      snprintf(src, sizeof(src), "syn.0.0/dir.%d/dir.%d/file.%d", a, b, c);
+      snprintf(dst, sizeof(dst), "syn.0.0/dir.%d/dir.%d/file.%d", d, e, f);
+      client->rename(src, dst, perms);
+    }
+    return;
+  }
+
+  if (1) {
+    // link fun
+    srand(0);
+    for (int i=0; i<100; i++) {
+      int s = 5;
+      int a = rand() % s;
+      int b = rand() % s;
+      int c = rand() % s;
+      int d = rand() % s;
+      int e = rand() % s;
+      int f = rand() % s;
+      char src[80];
+      char dst[80];
+      snprintf(src, sizeof(src), "syn.0.0/dir.%d/dir.%d/file.%d", a, b, c);
+      snprintf(dst, sizeof(dst), "syn.0.0/dir.%d/dir.%d/newlink.%d", d, e, f);
+      client->link(src, dst, perms);
+    }
+    srand(0);
+    for (int i=0; i<100; i++) {
+      int s = 5;
+      int a = rand() % s;
+      int b = rand() % s;
+      int c = rand() % s;
+      int d = rand() % s;
+      int e = rand() % s;
+      int f = rand() % s;
+      char src[80];
+      char dst[80];
+      snprintf(src, sizeof(src), "syn.0.0/dir.%d/dir.%d/file.%d", a, b, c);
+      snprintf(dst, sizeof(dst), "syn.0.0/dir.%d/dir.%d/newlink.%d", d, e, f);
+      client->unlink(dst, perms);
+    }
+
+    
+    return;
+  }
+
+  // link fun
+  client->mknod("one", 0755, perms);
+  client->mknod("two", 0755, perms);
+  client->link("one", "three", perms);
+  client->mkdir("dir", 0755, perms);
+  client->link("two", "/dir/twolink", perms);
+  client->link("dir/twolink", "four", perms);
+  
+  // unlink fun
+  client->mknod("a", 0644, perms);
+  client->unlink("a", perms);
+  client->mknod("b", 0644, perms);
+  client->link("b", "c", perms);
+  client->unlink("c", perms);
+  client->mkdir("d", 0755, perms);
+  client->unlink("d", perms);
+  client->rmdir("d", perms);
+
+  // rename fun
+  client->mknod("p1", 0644, perms);
+  client->mknod("p2", 0644, perms);
+  client->rename("p1","p2", perms);
+  client->mknod("p3", 0644, perms);
+  client->rename("p3","p4", perms);
+
+  // check dest dir ambiguity thing
+  client->mkdir("dir1", 0755, perms);
+  client->mkdir("dir2", 0755, perms);
+  client->rename("p2", "dir1/p2", perms);
+  client->rename("dir1/p2", "dir2/p2", perms);
+  client->rename("dir2/p2", "/p2", perms);
+  
+  // check primary+remote link merging
+  client->link("p2","p2.l", perms);
+  client->link("p4","p4.l", perms);
+  client->rename("p2.l", "p2", perms);
+  client->rename("p4", "p4.l", perms);
+
+  // check anchor updates
+  client->mknod("dir1/a", 0644, perms);
+  client->link("dir1/a", "da1", perms);
+  client->link("dir1/a", "da2", perms);
+  client->link("da2","da3", perms);
+  client->rename("dir1/a", "dir2/a", perms);
+  client->rename("dir2/a", "da2", perms);
+  client->rename("da1", "da2", perms);
+  client->rename("da2", "da3", perms);
+
+  // check directory renames
+  client->mkdir("dir3", 0755, perms);
+  client->mknod("dir3/asdf", 0644, perms);
+  client->mkdir("dir4", 0755, perms);
+  client->mkdir("dir5", 0755, perms);
+  client->mknod("dir5/asdf", 0644, perms);
+  client->rename("dir3", "dir4", perms); // ok
+  client->rename("dir4", "dir5", perms); // fail
+}
+
+int SyntheticClient::thrash_links(const char *basedir, int dirs, int files, int depth, int n)
+{
+  dout(1) << "thrash_links " << basedir << " " << dirs << " " << files << " " << depth
+	  << " links " << n
+	  << dendl;
+
+  if (time_to_stop()) return 0;
+
+  UserPerm perms = client->pick_my_perms();
+
+  srand(0);
+  if (1) {
+    bool renames = true; // thrash renames too?
+    for (int k=0; k<n; k++) {
+      
+      if (renames && rand() % 10 == 0) {
+	// rename some directories.  whee!
+	int dep = (rand() % depth) + 1;
+	string src = basedir;
+	{
+	  char t[80];
+	  for (int d=0; d<dep; d++) {
+	    int a = rand() % dirs;
+	    snprintf(t, sizeof(t), "/dir.%d", a);
+	    src += t;
+	  }
+	}
+	string dst = basedir;
+	{
+	  char t[80];
+	  for (int d=0; d<dep; d++) {
+	    int a = rand() % dirs;
+	    snprintf(t, sizeof(t), "/dir.%d", a);
+	    dst += t;
+	  }
+	}
+	
+	if (client->rename(dst.c_str(), "/tmp", perms) == 0) {
+	  client->rename(src.c_str(), dst.c_str(), perms);
+	  client->rename("/tmp", src.c_str(), perms);
+	}
+	continue;
+      } 
+      
+      // pick a dest dir
+      string src = basedir;
+      {
+	char t[80];
+	for (int d=0; d<depth; d++) {
+	  int a = rand() % dirs;
+	  snprintf(t, sizeof(t), "/dir.%d", a);
+	  src += t;
+	}
+	int a = rand() % files;
+	snprintf(t, sizeof(t), "/file.%d", a);
+	src += t;
+      }
+      string dst = basedir;
+      {
+	char t[80];
+	for (int d=0; d<depth; d++) {
+	  int a = rand() % dirs;
+	  snprintf(t, sizeof(t), "/dir.%d", a);
+	  dst += t;
+	}
+	int a = rand() % files;
+	snprintf(t, sizeof(t), "/file.%d", a);
+	dst += t;
+      }
+      
+      int o = rand() % 4;
+      switch (o) {
+      case 0: 
+	client->mknod(src.c_str(), 0755, perms);
+	if (renames) client->rename(src.c_str(), dst.c_str(), perms);
+	break;
+      case 1: 
+	client->mknod(src.c_str(), 0755, perms);
+	client->unlink(dst.c_str(), perms);
+	client->link(src.c_str(), dst.c_str(), perms); 
+	break;
+      case 2: client->unlink(src.c_str(), perms); break;
+      case 3: client->unlink(dst.c_str(), perms); break;
+	//case 4: client->mknod(src.c_str(), 0755, perms); break;
+	//case 5: client->mknod(dst.c_str(), 0755, perms); break;
+      }
+    }
+    return 0;
+  }
+
+  if (1) {
+    // now link shit up
+    for (int i=0; i<n; i++) {
+      if (time_to_stop()) return 0;
+      
+      char f[20];
+      
+      // pick a file
+      string file = basedir;
+      
+      if (depth) {
+	int d = rand() % (depth+1);
+	for (int k=0; k<d; k++) {
+	  snprintf(f, sizeof(f), "/dir.%d", rand() % dirs);
+	  file += f;
+	}
+      }
+      snprintf(f, sizeof(f), "/file.%d", rand() % files);
+      file += f;
+      
+      // pick a dir for our link
+      string ln = basedir;
+      if (depth) {
+	int d = rand() % (depth+1);
+	for (int k=0; k<d; k++) {
+	  snprintf(f, sizeof(f), "/dir.%d", rand() % dirs);
+	  ln += f;
+	}
+      }
+      snprintf(f, sizeof(f), "/ln.%d", i);
+      ln += f;
+      
+      client->link(file.c_str(), ln.c_str(), perms);
+    }
+  }
+  return 0;
+}
+
+
+
+
+void SyntheticClient::import_find(const char *base, const char *find, bool data)
+{
+  dout(1) << "import_find " << base << " from " << find << " data=" << data << dendl;
+
+  /* use this to gather the static trace:
+   *
+   *  find . -exec ls -dilsn --time-style=+%s \{\} \;
+   * or if it's wafl,
+   *  find . -path ./.snapshot -prune -o -exec ls -dilsn --time-style=+%s \{\} \;
+   *
+   */
+
+  UserPerm process_perms = client->pick_my_perms();
+
+  if (base[0] != '-') 
+    client->mkdir(base, 0755, process_perms);
+
+  ifstream f(find);
+  ceph_assert(f.is_open());
+  
+  int dirnum = 0;
+
+  while (!f.eof()) {
+    uint64_t ino;
+    int dunno, nlink;
+    string modestring;
+    int uid, gid;
+    off_t size;
+    time_t mtime;
+    string filename;
+    f >> ino;
+    if (f.eof()) break;
+    f >> dunno;
+    f >> modestring;
+    f >> nlink;
+    f >> uid;
+    f >> gid;
+    f >> size;
+    f >> mtime;
+    f.seekg(1, ios::cur);
+    getline(f, filename);
+    UserPerm perms(uid, gid);
+
+    // ignore "."
+    if (filename == ".") continue;
+
+    // remove leading ./
+    ceph_assert(filename[0] == '.' && filename[1] == '/');
+    filename = filename.substr(2);
+
+    // new leading dir?
+    int sp = filename.find("/");
+    if (sp < 0) dirnum++;
+
+    //dout(0) << "leading dir " << filename << " " << dirnum << dendl;
+    if (dirnum % num_client != client->get_nodeid()) {
+      dout(20) << "skipping leading dir " << dirnum << " " << filename << dendl;
+      continue;
+    }
+
+    // parse the mode
+    ceph_assert(modestring.length() == 10);
+    mode_t mode = 0;
+    switch (modestring[0]) {
+    case 'd': mode |= S_IFDIR; break;
+    case 'l': mode |= S_IFLNK; break;
+    default:
+    case '-': mode |= S_IFREG; break;
+    }
+    if (modestring[1] == 'r') mode |= 0400;
+    if (modestring[2] == 'w') mode |= 0200;
+    if (modestring[3] == 'x') mode |= 0100;
+    if (modestring[4] == 'r') mode |= 040;
+    if (modestring[5] == 'w') mode |= 020;
+    if (modestring[6] == 'x') mode |= 010;
+    if (modestring[7] == 'r') mode |= 04;
+    if (modestring[8] == 'w') mode |= 02;
+    if (modestring[9] == 'x') mode |= 01;
+
+    dout(20) << " mode " << modestring << " to " << oct << mode << dec << dendl;
+
+    if (S_ISLNK(mode)) {
+      // target vs destination
+      int pos = filename.find(" -> ");
+      ceph_assert(pos > 0);
+      string link;
+      if (base[0] != '-') {
+	link = base;
+	link += "/";
+      }
+      link += filename.substr(0, pos);
+      string target;
+      if (filename[pos+4] == '/') {
+	if (base[0] != '-') 
+	  target = base;
+	target += filename.substr(pos + 4);
+      } else {
+	target = filename.substr(pos + 4);
+      }
+      dout(10) << "symlink from '" << link << "' -> '" << target << "'" << dendl;
+      client->symlink(target.c_str(), link.c_str(), perms);
+    } else {
+      string f;
+      if (base[0] != '-') {
+	f = base;
+	f += "/";
+      }
+      f += filename;
+      if (S_ISDIR(mode)) {
+	client->mkdir(f.c_str(), mode, perms);
+      } else {
+	int fd = client->open(f.c_str(), O_WRONLY|O_CREAT, perms, mode & 0777);
+	ceph_assert(fd > 0);	
+	if (data) {
+	  client->write(fd, "", 0, size);
+	} else {
+	  client->truncate(f.c_str(), size, perms);
+	}
+	client->close(fd);
+
+	//client->chmod(f.c_str(), mode & 0777, perms, process_perms);
+	client->chown(f.c_str(), uid, gid, process_perms);
+
+	struct utimbuf ut;
+	ut.modtime = mtime;
+	ut.actime = mtime;
+	client->utime(f.c_str(), &ut, perms);
+      }
+    }
+  }
+  
+
+}
+
+
+int SyntheticClient::lookup_hash(inodeno_t ino, inodeno_t dirino,
+				 const char *name, const UserPerm& perms)
+{
+  int r = client->lookup_hash(ino, dirino, name, perms);
+  dout(0) << "lookup_hash(" << ino << ", #" << dirino << "/" << name << ") = " << r << dendl;
+  return r;
+}
+
+int SyntheticClient::lookup_ino(inodeno_t ino, const UserPerm& perms)
+{
+  int r = client->lookup_ino(ino, perms);
+  dout(0) << "lookup_ino(" << ino << ") = " << r << dendl;
+  return r;
+}
+
+int SyntheticClient::chunk_file(string &filename)
+{
+  UserPerm perms = client->pick_my_perms();
+  int fd = client->open(filename.c_str(), O_RDONLY, perms);
+  if (fd < 0)
+    return fd;
+
+  struct stat st;
+  int ret = client->fstat(fd, &st, perms);
+  if (ret < 0) {
+    client->close(fd);
+    return ret;
+  }
+  uint64_t size = st.st_size;
+  dout(0) << "file " << filename << " size is " << size << dendl;
+
+  inode_t inode{};
+  inode.ino = st.st_ino;
+  ret = client->fdescribe_layout(fd, &inode.layout);
+  ceph_assert(ret == 0); // otherwise fstat did a bad thing
+
+  uint64_t pos = 0;
+  bufferlist from_before;
+  while (pos < size) {
+    int get = std::min<int>(size - pos, 1048576);
+
+    ceph::mutex flock = ceph::make_mutex("synclient chunk_file lock");
+    ceph::condition_variable cond;
+    bool done;
+    bufferlist bl;
+    {
+      std::unique_lock locker{flock};
+      Context *onfinish = new C_SafeCond(flock, cond, &done);
+      client->filer->read(inode.ino, &inode.layout, CEPH_NOSNAP, pos, get, &bl, 0,
+			  onfinish);
+      cond.wait(locker, [&done] { return done; });
+    }
+    dout(0) << "got " << bl.length() << " bytes at " << pos << dendl;
+    
+    if (from_before.length()) {
+      dout(0) << " including bit from previous block" << dendl;
+      pos -= from_before.length();
+      from_before.claim_append(bl);
+      bl.swap(from_before);
+    }      
+
+    // ....
+
+    // keep last 32 bytes around
+    from_before.clear();
+    from_before.substr_of(bl, bl.length()-32, 32);
+
+    pos += bl.length();
+  }
+
+  client->close(fd);
+  return 0;
+}
+
+
+
+void SyntheticClient::mksnap(const char *base, const char *name, const UserPerm& perms)
+{
+  client->mksnap(base, name, perms);
+}
+
+void SyntheticClient::rmsnap(const char *base, const char *name, const UserPerm& perms)
+{
+  client->rmsnap(base, name, perms);
+}
+
+void SyntheticClient::mksnapfile(const char *dir)
+{
+  UserPerm perms = client->pick_my_perms();
+  client->mkdir(dir, 0755, perms);
+
+  string f = dir;
+  f += "/foo";
+  int fd = client->open(f.c_str(), O_WRONLY|O_CREAT|O_TRUNC, perms);
+
+  char buf[1048576*4];
+  client->write(fd, buf, sizeof(buf), 0);
+  client->fsync(fd, true);
+  client->close(fd);
+  
+  string s = dir;
+  s += "/.snap/1";
+  client->mkdir(s.c_str(), 0755, perms);
+
+  fd = client->open(f.c_str(), O_WRONLY, perms);
+  client->write(fd, buf, 1048576*2, 1048576);
+  client->fsync(fd, true);
+  client->close(fd);
+}