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Diffstat (limited to 'src/mds/Mantle.cc')
-rw-r--r-- | src/mds/Mantle.cc | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/mds/Mantle.cc b/src/mds/Mantle.cc new file mode 100644 index 000000000..e9033bbd9 --- /dev/null +++ b/src/mds/Mantle.cc @@ -0,0 +1,142 @@ +// -*- 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) 2016 Michael Sevilla <mikesevilla3@gmail.com> + * + * 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 "mdstypes.h" +#include "MDSRank.h" +#include "Mantle.h" +#include "msg/Messenger.h" +#include "common/Clock.h" +#include "CInode.h" + +/* Note, by default debug_mds_balancer is 1/5. For debug messages 1<lvl<=5, + * should_gather (below) will be true; so, debug_mds will be ignored even if + * set to 20/20. For this reason, some messages may not appear in the log. + * Increase both debug levels to get expected output! + */ +#define dout_context g_ceph_context +#undef dout_prefix +#define dout_prefix *_dout << "mds.mantle " +#define mantle_dout(lvl) \ + do {\ + auto subsys = ceph_subsys_mds;\ + if ((dout_context)->_conf->subsys.should_gather(ceph_subsys_mds_balancer, lvl)) {\ + subsys = ceph_subsys_mds_balancer;\ + }\ + dout_impl(dout_context, ceph::dout::need_dynamic(subsys), lvl) dout_prefix + +#define mantle_dendl dendl; } while (0) + + +static int dout_wrapper(lua_State *L) +{ + int level = luaL_checkinteger(L, 1); + lua_concat(L, lua_gettop(L)-1); + mantle_dout(ceph::dout::need_dynamic(level)) << lua_tostring(L, 2) + << mantle_dendl; + return 0; +} + +int Mantle::balance(std::string_view script, + mds_rank_t whoami, + const std::vector<std::map<std::string, double>> &metrics, + std::map<mds_rank_t, double> &my_targets) +{ + lua_settop(L, 0); /* clear the stack */ + + /* load the balancer */ + if (luaL_loadstring(L, script.data())) { + mantle_dout(0) << "WARNING: mantle could not load balancer: " + << lua_tostring(L, -1) << mantle_dendl; + return -CEPHFS_EINVAL; + } + + /* tell the balancer which mds is making the decision */ + lua_pushinteger(L, (lua_Integer)whoami); + lua_setglobal(L, "whoami"); + + /* global mds metrics to hold all dictionaries */ + lua_newtable(L); + + /* push name of mds (i) and its metrics onto Lua stack */ + for (size_t i=0; i < metrics.size(); i++) { + lua_newtable(L); + + /* push values into this mds's table; setfield assigns key/pops val */ + for (const auto &it : metrics[i]) { + lua_pushnumber(L, it.second); + lua_setfield(L, -2, it.first.c_str()); + } + + /* in global mds table at stack[-3], set k=stack[-1] to v=stack[-2] */ + lua_seti(L, -2, i); + } + + /* set the name of the global mds table */ + lua_setglobal(L, "mds"); + + ceph_assert(lua_gettop(L) == 1); + if (lua_pcall(L, 0, 1, 0) != LUA_OK) { + mantle_dout(0) << "WARNING: mantle could not execute script: " + << lua_tostring(L, -1) << mantle_dendl; + return -CEPHFS_EINVAL; + } + + /* parse response by iterating over Lua stack */ + if (lua_istable(L, -1) == 0) { + mantle_dout(0) << "WARNING: mantle script returned a malformed response" << mantle_dendl; + return -CEPHFS_EINVAL; + } + + /* fill in return value */ + for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1)) { + if (!lua_isinteger(L, -2) || !lua_isnumber(L, -1)) { + mantle_dout(0) << "WARNING: mantle script returned a malformed response" << mantle_dendl; + return -CEPHFS_EINVAL; + } + mds_rank_t rank(lua_tointeger(L, -2)); + my_targets[rank] = lua_tonumber(L, -1); + } + + return 0; +} + +Mantle::Mantle (void) +{ + /* build lua vm state */ + L = luaL_newstate(); + if (!L) { + mantle_dout(0) << "WARNING: mantle could not load Lua state" << mantle_dendl; + throw std::bad_alloc(); + } + + /* balancer policies can use basic Lua functions */ + static const luaL_Reg loadedlibs[] = { + {"_G", luaopen_base}, + {LUA_COLIBNAME, luaopen_coroutine}, + {LUA_STRLIBNAME, luaopen_string}, + {LUA_MATHLIBNAME, luaopen_math}, + {LUA_TABLIBNAME, luaopen_table}, + {LUA_UTF8LIBNAME, luaopen_utf8}, + {NULL, NULL} + }; + + const luaL_Reg *lib; + for (lib = loadedlibs; lib->func; lib++) { + luaL_requiref(L, lib->name, lib->func, 1); + lua_pop(L, 1); /* remove lib */ + } + + /* setup debugging */ + lua_register(L, "BAL_LOG", dout_wrapper); +} |