Adding upstream version 14.2.21.upstream/14.2.21upstream

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

1 files changed, 772 insertions, 0 deletions

diff --git a/src/test/fio/fio_ceph_objectstore.cc b/src/test/fio/fio_ceph_objectstore.cc
new file mode 100644
index 00000000..b8c29624
--- /dev/null
+++ b/src/test/fio/fio_ceph_objectstore.cc
@@ -0,0 +1,772 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ *  Ceph ObjectStore engine
+ *
+ * IO engine using Ceph's ObjectStore class to test low-level performance of
+ * Ceph OSDs.
+ *
+ */
+
+#include <memory>
+#include <system_error>
+#include <vector>
+
+#include "os/ObjectStore.h"
+#include "global/global_init.h"
+#include "common/errno.h"
+#include "include/intarith.h"
+#include "include/stringify.h"
+#include "include/random.h"
+#include "common/perf_counters.h"
+
+#include <fio.h>
+#include <optgroup.h>
+
+#include "include/ceph_assert.h" // fio.h clobbers our assert.h
+#include <algorithm>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_
+
+namespace {
+
+/// fio configuration options read from the job file
+struct Options {
+  thread_data* td;
+  char* conf;
+  unsigned long long
+    oi_attr_len_low,
+    oi_attr_len_high,
+    snapset_attr_len_low,
+    snapset_attr_len_high,
+    pglog_omap_len_low,
+    pglog_omap_len_high,
+    pglog_dup_omap_len_low,
+    pglog_dup_omap_len_high,
+    _fastinfo_omap_len_low,
+    _fastinfo_omap_len_high;
+  unsigned simulate_pglog;
+  unsigned single_pool_mode;
+  unsigned preallocate_files;
+};
+
+template <class Func> // void Func(fio_option&)
+fio_option make_option(Func&& func)
+{
+  // zero-initialize and set common defaults
+  auto o = fio_option{};
+  o.category = FIO_OPT_C_ENGINE;
+  o.group    = FIO_OPT_G_RBD;
+  func(std::ref(o));
+  return o;
+}
+
+static std::vector<fio_option> ceph_options{
+  make_option([] (fio_option& o) {
+    o.name   = "conf";
+    o.lname  = "ceph configuration file";
+    o.type   = FIO_OPT_STR_STORE;
+    o.help   = "Path to a ceph configuration file";
+    o.off1   = offsetof(Options, conf);
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "oi_attr_len";
+    o.lname  = "OI Attr length";
+    o.type   = FIO_OPT_STR_VAL;
+    o.help   = "Set OI(aka '_') attribute to specified length";
+    o.off1   = offsetof(Options, oi_attr_len_low);
+    o.off2   = offsetof(Options, oi_attr_len_high);
+    o.def    = 0;
+    o.minval = 0;
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "snapset_attr_len";
+    o.lname  = "Attr 'snapset' length";
+    o.type   = FIO_OPT_STR_VAL;
+    o.help   = "Set 'snapset' attribute to specified length";
+    o.off1   = offsetof(Options, snapset_attr_len_low);
+    o.off2   = offsetof(Options, snapset_attr_len_high);
+    o.def    = 0;
+    o.minval = 0;
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "_fastinfo_omap_len";
+    o.lname  = "'_fastinfo' omap entry length";
+    o.type   = FIO_OPT_STR_VAL;
+    o.help   = "Set '_fastinfo' OMAP attribute to specified length";
+    o.off1   = offsetof(Options, _fastinfo_omap_len_low);
+    o.off2   = offsetof(Options, _fastinfo_omap_len_high);
+    o.def    = 0;
+    o.minval = 0;
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "pglog_simulation";
+    o.lname  = "pglog behavior simulation";
+    o.type   = FIO_OPT_BOOL;
+    o.help   = "Enables PG Log simulation behavior";
+    o.off1   = offsetof(Options, simulate_pglog);
+    o.def    = "0";
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "pglog_omap_len";
+    o.lname  = "pglog omap entry length";
+    o.type   = FIO_OPT_STR_VAL;
+    o.help   = "Set pglog omap entry to specified length";
+    o.off1   = offsetof(Options, pglog_omap_len_low);
+    o.off2   = offsetof(Options, pglog_omap_len_high);
+    o.def    = 0;
+    o.minval = 0;
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "pglog_dup_omap_len";
+    o.lname  = "uplicate pglog omap entry length";
+    o.type   = FIO_OPT_STR_VAL;
+    o.help   = "Set duplicate pglog omap entry to specified length";
+    o.off1   = offsetof(Options, pglog_dup_omap_len_low);
+    o.off2   = offsetof(Options, pglog_dup_omap_len_high);
+    o.def    = 0;
+    o.minval = 0;
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "single_pool_mode";
+    o.lname  = "single(shared among jobs) pool mode";
+    o.type   = FIO_OPT_BOOL;
+    o.help   = "Enables the mode when all jobs run against the same pool";
+    o.off1   = offsetof(Options, single_pool_mode);
+    o.def    = "0";
+  }),
+  make_option([] (fio_option& o) {
+    o.name   = "preallocate_files";
+    o.lname  = "preallocate files on init";
+    o.type   = FIO_OPT_BOOL;
+    o.help   = "Enables/disables file preallocation (touch and resize) on init";
+    o.off1   = offsetof(Options, preallocate_files);
+    o.def    = "1";
+  }),
+  {} // fio expects a 'null'-terminated list
+};
+
+
+struct Collection {
+  spg_t pg;
+  coll_t cid;
+  ObjectStore::CollectionHandle ch;
+  // Can't use mutex directly in vectors hence dynamic allocation
+
+  std::unique_ptr<std::mutex> lock;
+  uint64_t pglog_ver_head = 1;
+  uint64_t pglog_ver_tail = 1;
+  uint64_t pglog_dup_ver_tail = 1;
+
+  // use big pool ids to avoid clashing with existing collections
+  static constexpr int64_t MIN_POOL_ID = 0x0000ffffffffffff;
+
+  Collection(const spg_t& pg, ObjectStore::CollectionHandle _ch)
+    : pg(pg), cid(pg), ch(_ch),
+        lock(new std::mutex) {
+  }
+};
+
+int destroy_collections(
+  std::unique_ptr<ObjectStore>& os,
+  std::vector<Collection>& collections)
+{
+  ObjectStore::Transaction t;
+  bool failed = false;
+  // remove our collections
+  for (auto& coll : collections) {
+    ghobject_t pgmeta_oid(coll.pg.make_pgmeta_oid());
+    t.remove(coll.cid, pgmeta_oid);
+    t.remove_collection(coll.cid);
+    int r = os->queue_transaction(coll.ch, std::move(t));
+    if (r && !failed) {
+      derr << "Engine cleanup failed with " << cpp_strerror(-r) << dendl;
+      failed = true;
+    }
+  }
+  return 0;
+}
+
+int init_collections(std::unique_ptr<ObjectStore>& os,
+		      uint64_t pool,
+		      std::vector<Collection>& collections,
+		      uint64_t count)
+{
+  ceph_assert(count > 0);
+  collections.reserve(count);
+
+  const int split_bits = cbits(count - 1);
+
+  {
+    // propagate Superblock object to ensure proper functioning of tools that
+    // need it. E.g. ceph-objectstore-tool
+    coll_t cid(coll_t::meta());
+    bool exists = os->collection_exists(cid);
+    if (!exists) {
+      auto ch = os->create_new_collection(cid);
+
+      OSDSuperblock superblock;
+      bufferlist bl;
+      encode(superblock, bl);
+
+      ObjectStore::Transaction t;
+      t.create_collection(cid, split_bits);
+      t.write(cid, OSD_SUPERBLOCK_GOBJECT, 0, bl.length(), bl);
+      int r = os->queue_transaction(ch, std::move(t));
+
+      if (r < 0) {
+	derr << "Failure to write OSD superblock: " << cpp_strerror(-r) << dendl;
+	return r;
+      }
+    }
+  }
+
+  for (uint32_t i = 0; i < count; i++) {
+    auto pg = spg_t{pg_t{i, pool}};
+    coll_t cid(pg);
+
+    bool exists = os->collection_exists(cid);
+    auto ch = exists ?
+      os->open_collection(cid) :
+      os->create_new_collection(cid) ;
+
+    collections.emplace_back(pg, ch);
+
+    ObjectStore::Transaction t;
+    auto& coll = collections.back();
+    if (!exists) {
+      t.create_collection(coll.cid, split_bits);
+      ghobject_t pgmeta_oid(coll.pg.make_pgmeta_oid());
+      t.touch(coll.cid, pgmeta_oid);
+      int r = os->queue_transaction(coll.ch, std::move(t));
+      if (r) {
+	derr << "Engine init failed with " << cpp_strerror(-r) << dendl;
+	destroy_collections(os, collections);
+	return r;
+      }
+    }
+  }
+  return 0;
+}
+
+/// global engine state shared between all jobs within the process. this
+/// includes g_ceph_context and the ObjectStore instance
+struct Engine {
+  /// the initial g_ceph_context reference to be dropped on destruction
+  boost::intrusive_ptr<CephContext> cct;
+  std::unique_ptr<ObjectStore> os;
+
+  std::vector<Collection> collections; //< shared collections to spread objects over
+
+  std::mutex lock;
+  int ref_count;
+  const bool unlink; //< unlink objects on destruction
+
+  explicit Engine(thread_data* td);
+  ~Engine();
+
+  static Engine* get_instance(thread_data* td) {
+    // note: creates an Engine with the options associated with the first job
+    static Engine engine(td);
+    return &engine;
+  }
+
+  void ref() {
+    std::lock_guard<std::mutex> l(lock);
+    ++ref_count;
+  }
+  void deref() {
+    std::lock_guard<std::mutex> l(lock);
+    --ref_count;
+    if (!ref_count) {
+      ostringstream ostr;
+      Formatter* f = Formatter::create("json-pretty", "json-pretty", "json-pretty");
+      cct->get_perfcounters_collection()->dump_formatted(f, false);
+      ostr << "FIO plugin ";
+      f->flush(ostr);
+      if (g_conf()->rocksdb_perf) {
+        os->get_db_statistics(f);
+        ostr << "FIO get_db_statistics ";
+        f->flush(ostr);
+      }
+      ostr << "Mempools: ";
+      f->open_object_section("mempools");
+      mempool::dump(f);
+      f->close_section();
+      f->flush(ostr);
+      
+      ostr << "Generate db histogram: ";
+      os->generate_db_histogram(f);
+      f->flush(ostr);
+      delete f;
+
+      if (unlink) {
+	destroy_collections(os, collections);
+      }
+      os->umount();
+      dout(0) <<  ostr.str() << dendl;
+    }
+  }
+};
+
+Engine::Engine(thread_data* td)
+  : ref_count(0),
+    unlink(td->o.unlink)
+{
+  // add the ceph command line arguments
+  auto o = static_cast<Options*>(td->eo);
+  if (!o->conf) {
+    throw std::runtime_error("missing conf option for ceph configuration file");
+  }
+  std::vector<const char*> args{
+    "-i", "0", // identify as osd.0 for osd_data and osd_journal
+    "--conf", o->conf, // use the requested conf file
+  };
+  if (td->o.directory) { // allow conf files to use ${fio_dir} for data
+    args.emplace_back("--fio_dir");
+    args.emplace_back(td->o.directory);
+  }
+
+  // claim the g_ceph_context reference and release it on destruction
+  cct = global_init(nullptr, args, CEPH_ENTITY_TYPE_OSD,
+		    CODE_ENVIRONMENT_UTILITY,
+		    CINIT_FLAG_NO_DEFAULT_CONFIG_FILE);
+  common_init_finish(g_ceph_context);
+
+  // create the ObjectStore
+  os.reset(ObjectStore::create(g_ceph_context,
+                               g_conf().get_val<std::string>("osd objectstore"),
+                               g_conf().get_val<std::string>("osd data"),
+                               g_conf().get_val<std::string>("osd journal")));
+  if (!os)
+    throw std::runtime_error("bad objectstore type " + g_conf()->osd_objectstore);
+
+  unsigned num_shards;
+  if(g_conf()->osd_op_num_shards)
+    num_shards = g_conf()->osd_op_num_shards;
+  else if(os->is_rotational())
+    num_shards = g_conf()->osd_op_num_shards_hdd;
+  else
+    num_shards = g_conf()->osd_op_num_shards_ssd;
+  os->set_cache_shards(num_shards);
+
+  //normalize options
+  o->oi_attr_len_high = max(o->oi_attr_len_low, o->oi_attr_len_high);
+  o->snapset_attr_len_high = max(o->snapset_attr_len_low,
+				      o->snapset_attr_len_high);
+  o->pglog_omap_len_high = max(o->pglog_omap_len_low,
+				    o->pglog_omap_len_high);
+  o->pglog_dup_omap_len_high = max(o->pglog_dup_omap_len_low,
+					o->pglog_dup_omap_len_high);
+  o->_fastinfo_omap_len_high = max(o->_fastinfo_omap_len_low,
+					o->_fastinfo_omap_len_high);
+
+  int r = os->mkfs();
+  if (r < 0)
+    throw std::system_error(-r, std::system_category(), "mkfs failed");
+
+  r = os->mount();
+  if (r < 0)
+    throw std::system_error(-r, std::system_category(), "mount failed");
+
+  // create shared collections up to osd_pool_default_pg_num
+  if (o->single_pool_mode) {
+    uint64_t count = g_conf().get_val<uint64_t>("osd_pool_default_pg_num");
+    if (count > td->o.nr_files)
+      count = td->o.nr_files;
+    init_collections(os, Collection::MIN_POOL_ID, collections, count);
+  }
+}
+
+Engine::~Engine()
+{
+  ceph_assert(!ref_count);
+}
+
+struct Object {
+  ghobject_t oid;
+  Collection& coll;
+
+  Object(const char* name, Collection& coll)
+    : oid(hobject_t(name, "", CEPH_NOSNAP, coll.pg.ps(), coll.pg.pool(), "")),
+      coll(coll) {}
+};
+
+/// treat each fio job either like a separate pool with its own collections and objects
+/// or just a client using its own objects from the shared pool
+struct Job {
+  Engine* engine; //< shared ptr to the global Engine
+  std::vector<Collection> collections; //< job's private collections to spread objects over
+  std::vector<Object> objects; //< associate an object with each fio_file
+  std::vector<io_u*> events; //< completions for fio_ceph_os_event()
+  const bool unlink; //< unlink objects on destruction
+
+  bufferptr one_for_all_data; //< preallocated buffer long enough
+                              //< to use for vairious operations
+
+  Job(Engine* engine, const thread_data* td);
+  ~Job();
+};
+
+Job::Job(Engine* engine, const thread_data* td)
+  : engine(engine),
+    events(td->o.iodepth),
+    unlink(td->o.unlink)
+{
+  engine->ref();
+  auto o = static_cast<Options*>(td->eo);
+  unsigned long long max_data = max(o->oi_attr_len_high,
+				  o->snapset_attr_len_high);
+  max_data = max(max_data, o->pglog_omap_len_high);
+  max_data = max(max_data, o->pglog_dup_omap_len_high);
+  max_data = max(max_data, o->_fastinfo_omap_len_high);
+  one_for_all_data = buffer::create(max_data);
+
+  std::vector<Collection>* colls;
+  // create private collections up to osd_pool_default_pg_num
+  if (!o->single_pool_mode) {
+    uint64_t count = g_conf().get_val<uint64_t>("osd_pool_default_pg_num");
+    if (count > td->o.nr_files)
+      count = td->o.nr_files;
+    // use the fio thread_number for our unique pool id
+    const uint64_t pool = Collection::MIN_POOL_ID + td->thread_number + 1;
+    init_collections(engine->os, pool, collections, count);
+    colls = &collections;
+  } else {
+    colls = &engine->collections;
+  }
+  const uint64_t file_size = td->o.size / max(1u, td->o.nr_files);
+  ObjectStore::Transaction t;
+
+  // create an object for each file in the job
+  objects.reserve(td->o.nr_files);
+  for (uint32_t i = 0; i < td->o.nr_files; i++) {
+    auto f = td->files[i];
+    f->real_file_size = file_size;
+    f->engine_pos = i;
+
+    // associate each object with a collection in a round-robin fashion.
+    auto& coll = (*colls)[i % colls->size()];
+
+    objects.emplace_back(f->file_name, coll);
+    if (o->preallocate_files) {
+      auto& oid = objects.back().oid;
+      t.touch(coll.cid, oid);
+      t.truncate(coll.cid, oid, file_size);
+      int r = engine->os->queue_transaction(coll.ch, std::move(t));
+      if (r) {
+        engine->deref();
+        throw std::system_error(r, std::system_category(), "job init");
+      }
+    }
+  }
+}
+
+Job::~Job()
+{
+  if (unlink) {
+    ObjectStore::Transaction t;
+    bool failed = false;
+    // remove our objects
+    for (auto& obj : objects) {
+      t.remove(obj.coll.cid, obj.oid);
+      int r = engine->os->queue_transaction(obj.coll.ch, std::move(t));
+      if (r && !failed) {
+	derr << "job cleanup failed with " << cpp_strerror(-r) << dendl;
+	failed = true;
+      }
+    }
+    destroy_collections(engine->os, collections);
+  }
+  engine->deref();
+}
+
+int fio_ceph_os_setup(thread_data* td)
+{
+  // if there are multiple jobs, they must run in the same process against a
+  // single instance of the ObjectStore. explicitly disable fio's default
+  // job-per-process configuration
+  td->o.use_thread = 1;
+
+  try {
+    // get or create the global Engine instance
+    auto engine = Engine::get_instance(td);
+    // create a Job for this thread
+    td->io_ops_data = new Job(engine, td);
+  } catch (std::exception& e) {
+    std::cerr << "setup failed with " << e.what() << std::endl;
+    return -1;
+  }
+  return 0;
+}
+
+void fio_ceph_os_cleanup(thread_data* td)
+{
+  auto job = static_cast<Job*>(td->io_ops_data);
+  td->io_ops_data = nullptr;
+  delete job;
+}
+
+
+io_u* fio_ceph_os_event(thread_data* td, int event)
+{
+  // return the requested event from fio_ceph_os_getevents()
+  auto job = static_cast<Job*>(td->io_ops_data);
+  return job->events[event];
+}
+
+int fio_ceph_os_getevents(thread_data* td, unsigned int min,
+                          unsigned int max, const timespec* t)
+{
+  auto job = static_cast<Job*>(td->io_ops_data);
+  unsigned int events = 0;
+  io_u* u = NULL;
+  unsigned int i = 0;
+
+  // loop through inflight ios until we find 'min' completions
+  do {
+    io_u_qiter(&td->io_u_all, u, i) {
+      if (!(u->flags & IO_U_F_FLIGHT))
+        continue;
+
+      if (u->engine_data) {
+        u->engine_data = nullptr;
+        job->events[events] = u;
+        events++;
+      }
+    }
+    if (events >= min)
+      break;
+    usleep(100);
+  } while (1);
+
+  return events;
+}
+
+/// completion context for ObjectStore::queue_transaction()
+class UnitComplete : public Context {
+  io_u* u;
+ public:
+  explicit UnitComplete(io_u* u) : u(u) {}
+  void finish(int r) {
+    // mark the pointer to indicate completion for fio_ceph_os_getevents()
+    u->engine_data = reinterpret_cast<void*>(1ull);
+  }
+};
+
+enum fio_q_status fio_ceph_os_queue(thread_data* td, io_u* u)
+{
+  fio_ro_check(td, u);
+
+
+
+  auto o = static_cast<const Options*>(td->eo);
+  auto job = static_cast<Job*>(td->io_ops_data);
+  auto& object = job->objects[u->file->engine_pos];
+  auto& coll = object.coll;
+  auto& os = job->engine->os;
+
+  if (u->ddir == DDIR_WRITE) {
+    // provide a hint if we're likely to read this data back
+    const int flags = td_rw(td) ? CEPH_OSD_OP_FLAG_FADVISE_WILLNEED : 0;
+
+    bufferlist bl;
+    bl.push_back(buffer::copy(reinterpret_cast<char*>(u->xfer_buf),
+                              u->xfer_buflen ) );
+
+    map<string,bufferptr> attrset;
+    map<string, bufferlist> omaps;
+    // enqueue a write transaction on the collection's handle
+    ObjectStore::Transaction t;
+    char ver_key[64];
+
+    // fill attrs if any
+    if (o->oi_attr_len_high) {
+      ceph_assert(o->oi_attr_len_high >= o->oi_attr_len_low);
+      // fill with the garbage as we do not care of the actual content...
+      job->one_for_all_data.set_length(
+        ceph::util::generate_random_number(
+	  o->oi_attr_len_low, o->oi_attr_len_high));
+      attrset["_"] = job->one_for_all_data;
+    }
+    if (o->snapset_attr_len_high) {
+      ceph_assert(o->snapset_attr_len_high >= o->snapset_attr_len_low);
+      job->one_for_all_data.set_length(
+        ceph::util::generate_random_number
+	  (o->snapset_attr_len_low, o->snapset_attr_len_high));
+      attrset["snapset"] = job->one_for_all_data;
+
+    }
+    if (o->_fastinfo_omap_len_high) {
+      ceph_assert(o->_fastinfo_omap_len_high >= o->_fastinfo_omap_len_low);
+      // fill with the garbage as we do not care of the actual content...
+      job->one_for_all_data.set_length(
+	ceph::util::generate_random_number(
+	  o->_fastinfo_omap_len_low, o->_fastinfo_omap_len_high));
+      omaps["_fastinfo"].append(job->one_for_all_data);
+    }
+
+    uint64_t pglog_trim_head = 0, pglog_trim_tail = 0;
+    uint64_t pglog_dup_trim_head = 0, pglog_dup_trim_tail = 0;
+    if (o->simulate_pglog) {
+
+      uint64_t pglog_ver_cnt = 0;
+      {
+	std::lock_guard<std::mutex> l(*coll.lock);
+        pglog_ver_cnt = coll.pglog_ver_head++;
+	if (o->pglog_omap_len_high &&
+	    pglog_ver_cnt >=
+	      coll.pglog_ver_tail +
+	        g_conf()->osd_min_pg_log_entries + g_conf()->osd_pg_log_trim_min) {
+	  pglog_trim_tail = coll.pglog_ver_tail;
+	  coll.pglog_ver_tail = pglog_trim_head =
+	    pglog_trim_tail + g_conf()->osd_pg_log_trim_min;
+
+	  if (o->pglog_dup_omap_len_high &&
+	      pglog_ver_cnt >=
+		coll.pglog_dup_ver_tail + g_conf()->osd_pg_log_dups_tracked +
+		  g_conf()->osd_pg_log_trim_min) {
+	    pglog_dup_trim_tail = coll.pglog_dup_ver_tail;
+	    coll.pglog_dup_ver_tail = pglog_dup_trim_head =
+	      pglog_dup_trim_tail + g_conf()->osd_pg_log_trim_min;
+	  }
+	}
+      }
+
+      if (o->pglog_omap_len_high) {
+	ceph_assert(o->pglog_omap_len_high >= o->pglog_omap_len_low);
+	snprintf(ver_key, sizeof(ver_key),
+	  "0000000011.%020llu", (unsigned long long)pglog_ver_cnt);
+	// fill with the garbage as we do not care of the actual content...
+        job->one_for_all_data.set_length(
+	  ceph::util::generate_random_number(
+	    o->pglog_omap_len_low, o->pglog_omap_len_high));
+	omaps[ver_key].append(job->one_for_all_data);
+      }
+      if (o->pglog_dup_omap_len_high) {
+	//insert dup
+	ceph_assert(o->pglog_dup_omap_len_high >= o->pglog_dup_omap_len_low);
+        for( auto i = pglog_trim_tail; i < pglog_trim_head; ++i) {
+	  snprintf(ver_key, sizeof(ver_key),
+	    "dup_0000000011.%020llu", (unsigned long long)i);
+	  // fill with the garbage as we do not care of the actual content...
+	  job->one_for_all_data.set_length(
+	    ceph::util::generate_random_number(
+	      o->pglog_dup_omap_len_low, o->pglog_dup_omap_len_high));
+	  omaps[ver_key].append(job->one_for_all_data);
+	}
+      }
+    }
+
+    if (attrset.size()) {
+      t.setattrs(coll.cid, object.oid, attrset);
+    }
+    t.write(coll.cid, object.oid, u->offset, u->xfer_buflen, bl, flags);
+
+    set<string> rmkeys;
+    for( auto i = pglog_trim_tail; i < pglog_trim_head; ++i) {
+	snprintf(ver_key, sizeof(ver_key),
+	  "0000000011.%020llu", (unsigned long long)i);
+	rmkeys.emplace(ver_key);
+    }
+    for( auto i = pglog_dup_trim_tail; i < pglog_dup_trim_head; ++i) {
+	snprintf(ver_key, sizeof(ver_key),
+	  "dup_0000000011.%020llu", (unsigned long long)i);
+	rmkeys.emplace(ver_key);
+    }
+
+    if (rmkeys.size()) {
+      ghobject_t pgmeta_oid(coll.pg.make_pgmeta_oid());
+      t.omap_rmkeys(coll.cid, pgmeta_oid, rmkeys);
+    }
+
+    if (omaps.size()) {
+      ghobject_t pgmeta_oid(coll.pg.make_pgmeta_oid());
+      t.omap_setkeys(coll.cid, pgmeta_oid, omaps);
+    }
+    t.register_on_commit(new UnitComplete(u));
+    os->queue_transaction(coll.ch,
+                          std::move(t));
+    return FIO_Q_QUEUED;
+  }
+
+  if (u->ddir == DDIR_READ) {
+    // ObjectStore reads are synchronous, so make the call and return COMPLETED
+    bufferlist bl;
+    int r = os->read(coll.ch, object.oid, u->offset, u->xfer_buflen, bl);
+    if (r < 0) {
+      u->error = r;
+      td_verror(td, u->error, "xfer");
+    } else {
+      bl.copy(0, bl.length(), static_cast<char*>(u->xfer_buf));
+      u->resid = u->xfer_buflen - r;
+    }
+    return FIO_Q_COMPLETED;
+  }
+
+  derr << "WARNING: Only DDIR_READ and DDIR_WRITE are supported!" << dendl;
+  u->error = -EINVAL;
+  td_verror(td, u->error, "xfer");
+  return FIO_Q_COMPLETED;
+}
+
+int fio_ceph_os_commit(thread_data* td)
+{
+  // commit() allows the engine to batch up queued requests to be submitted all
+  // at once. it would be natural for queue() to collect transactions in a list,
+  // and use commit() to pass them all to ObjectStore::queue_transactions(). but
+  // because we spread objects over multiple collections, we a) need to use a
+  // different sequencer for each collection, and b) are less likely to see a
+  // benefit from batching requests within a collection
+  return 0;
+}
+
+// open/close are noops. we set the FIO_DISKLESSIO flag in ioengine_ops to
+// prevent fio from creating the files
+int fio_ceph_os_open(thread_data* td, fio_file* f) { return 0; }
+int fio_ceph_os_close(thread_data* td, fio_file* f) { return 0; }
+
+int fio_ceph_os_io_u_init(thread_data* td, io_u* u)
+{
+  // no data is allocated, we just use the pointer as a boolean 'completed' flag
+  u->engine_data = nullptr;
+  return 0;
+}
+
+void fio_ceph_os_io_u_free(thread_data* td, io_u* u)
+{
+  u->engine_data = nullptr;
+}
+
+
+// ioengine_ops for get_ioengine()
+struct ceph_ioengine : public ioengine_ops {
+  ceph_ioengine() : ioengine_ops({}) {
+    name        = "ceph-os";
+    version     = FIO_IOOPS_VERSION;
+    flags       = FIO_DISKLESSIO;
+    setup       = fio_ceph_os_setup;
+    queue       = fio_ceph_os_queue;
+    commit      = fio_ceph_os_commit;
+    getevents   = fio_ceph_os_getevents;
+    event       = fio_ceph_os_event;
+    cleanup     = fio_ceph_os_cleanup;
+    open_file   = fio_ceph_os_open;
+    close_file  = fio_ceph_os_close;
+    io_u_init   = fio_ceph_os_io_u_init;
+    io_u_free   = fio_ceph_os_io_u_free;
+    options     = ceph_options.data();
+    option_struct_size = sizeof(struct Options);
+  }
+};
+
+} // anonymous namespace
+
+extern "C" {
+// the exported fio engine interface
+void get_ioengine(struct ioengine_ops** ioengine_ptr) {
+  static ceph_ioengine ioengine;
+  *ioengine_ptr = &ioengine;
+}
+} // extern "C"