X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/2119e6533d557066a41c25915f77b2e64a5ba812..e6e7aa1dcecc9e26fe09ede088b3ef9848b18eb3:/src/plugins/host_load.cpp diff --git a/src/plugins/host_load.cpp b/src/plugins/host_load.cpp index 5387b3c214..73debe7269 100644 --- a/src/plugins/host_load.cpp +++ b/src/plugins/host_load.cpp @@ -1,19 +1,34 @@ -/* Copyright (c) 2010-2018. The SimGrid Team. All rights reserved. */ +/* Copyright (c) 2010-2019. The SimGrid Team. All rights reserved. */ /* This program is free software; you can redistribute it and/or modify it * under the terms of the license (GNU LGPL) which comes with this package. */ #include "simgrid/plugins/load.h" #include "src/include/surf/surf.hpp" +#include "src/kernel/activity/ExecImpl.hpp" #include "src/plugins/vm/VirtualMachineImpl.hpp" #include +// Makes sure that this plugin can be activated from the command line with ``--cfg=plugin:host_load`` SIMGRID_REGISTER_PLUGIN(host_load, "Cpu load", &sg_host_load_plugin_init) -/** @addtogroup plugin_load +/** @defgroup plugin_host_load -This plugin makes it very simple for users to obtain the current load for each host. + @rst +Simple plugin that monitors the current load for each host. + +In addition, this constitutes a good introductory example on how to write a plugin. +It attaches an extension to each host to store some data, and places callbacks in the following signals: + + - :cpp:member:`simgrid::s4u::Host::on_creation`: Attach a new extension to the newly created host. + - :cpp:member:`simgrid::s4u::Exec::on_start`: Make note that a new execution started, increasing the load. + - :cpp:member:`simgrid::s4u::Exec::on_completion`: Make note that an execution completed, decreasing the load. + - :cpp:member:`simgrid::s4u::Host::on_state_change`: Do what is appropriate when the host gets suspended, turned off or similar. + - :cpp:member:`simgrid::s4u::Host::on_speed_change`: Do what is appropriate when the DVFS is modified. + + Note that extensions are automatically destroyed when the host gets destroyed. + @endrst */ XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_plugin_load, surf, "Logging specific to the HostLoad plugin"); @@ -21,6 +36,23 @@ XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_plugin_load, surf, "Logging specific to the namespace simgrid { namespace plugin { +static const double activity_uninitialized_remaining_cost = -1; + +/** This class stores the extra data needed by this plugin about a given host + * + * It is stored as an extension of s4u::Host. Such extensions are retrieved by type as follows: + * + * @verbatim + * simgrid::s4u::Host* this_host = ???; + * this_extension = host->extension(); + * @endverbatim + * + * If no extension of that type was ever attached to the inspected object, the ``extension()`` template returns + * nullptr. + * + * Please refer to the implementation of ``sg_host_load_plugin_init()`` to see the extension objects are attached to + * hosts at initialization time. + */ class HostLoad { public: static simgrid::xbt::Extension EXTENSION_ID; @@ -30,7 +62,7 @@ public: , last_updated_(surf_get_clock()) , last_reset_(surf_get_clock()) , current_speed_(host_->get_speed()) - , current_flops_(host_->pimpl_cpu->get_constraint()->get_usage()) + , current_flops_(host_->get_load()) , theor_max_flops_(0) { } @@ -40,15 +72,25 @@ public: explicit HostLoad(simgrid::s4u::Host&& ptr) = delete; double get_current_load(); - double get_average_load() { return (theor_max_flops_ == 0) ? 0 : computed_flops_ / theor_max_flops_; }; - double get_computed_flops() { return computed_flops_; } - double get_idle_time() { return idle_time_; } /** Return idle time since last reset */ - double get_total_idle_time() { return total_idle_time_; } /** Return idle time over the whole simulation */ + /** Get the the average load since last reset(), as a ratio + * + * That's the ratio (amount of flops that were actually computed) / (amount of flops that could have been computed at full speed) + */ + double get_average_load() { update(); return (theor_max_flops_ == 0) ? 0 : computed_flops_ / theor_max_flops_; }; + /** Amount of flops computed since last reset() */ + double get_computed_flops() { update(); return computed_flops_; } + /** Return idle time since last reset() */ + double get_idle_time() { update(); return idle_time_; } + /** Return idle time over the whole simulation */ + double get_total_idle_time() { update(); return total_idle_time_; } void update(); + void add_activity(simgrid::kernel::activity::ExecImpl* activity); void reset(); private: simgrid::s4u::Host* host_ = nullptr; + /* Stores all currently ongoing activities (computations) on this machine */ + std::map current_activities; double last_updated_ = 0; double last_reset_ = 0; /** @@ -63,22 +105,48 @@ private: double current_flops_ = 0; double computed_flops_ = 0; double idle_time_ = 0; - double total_idle_time_ = 0; /* This gets never reset */ + double total_idle_time_ = 0; /* This updated but never gets reset */ double theor_max_flops_ = 0; }; +// Create the static field that the extension mechanism needs simgrid::xbt::Extension HostLoad::EXTENSION_ID; +void HostLoad::add_activity(simgrid::kernel::activity::ExecImpl* activity) +{ + current_activities.insert({activity, activity_uninitialized_remaining_cost}); +} + void HostLoad::update() { double now = surf_get_clock(); + // This loop updates the flops that the host executed for the ongoing computations + auto iter = begin(current_activities); + while (iter != end(current_activities)) { + auto& activity = iter->first; // Just an alias + auto& remaining_cost_after_last_update = iter->second; // Just an alias + auto& action = activity->surf_action_; + auto current_iter = iter; + ++iter; + + if (action != nullptr && action->get_finish_time() != now && activity->state_ == e_smx_state_t::SIMIX_RUNNING) { + if (remaining_cost_after_last_update == activity_uninitialized_remaining_cost) { + remaining_cost_after_last_update = action->get_cost(); + } + double computed_flops_since_last_update = remaining_cost_after_last_update - /*remaining now*/activity->get_remaining(); + computed_flops_ += computed_flops_since_last_update; + remaining_cost_after_last_update = activity->get_remaining(); + } + else if (activity->state_ == e_smx_state_t::SIMIX_DONE) { + computed_flops_ += remaining_cost_after_last_update; + current_activities.erase(current_iter); + } + } + /* Current flop per second computed by the cpu; current_flops = k * pstate_speed_in_flops, k @in {0, 1, ..., cores-1} * designates number of active cores; will be 0 if CPU is currently idle */ - current_flops_ = host_->pimpl_cpu->get_constraint()->get_usage(); - - /* flops == pstate_speed * cores_being_currently_used */ - computed_flops_ += (now - last_updated_) * current_flops_; + current_flops_ = host_->get_load(); if (current_flops_ == 0) { idle_time_ += (now - last_updated_); @@ -91,19 +159,23 @@ void HostLoad::update() last_updated_ = now; } -/** - * WARNING: This function does not guarantee that you have the real load at any time imagine all actions on your CPU - * terminate at time t. Your load is then 0. Then you query the load (still 0) and then another action starts (still at - * time t!). This means that the load was never really 0 (because the time didn't advance) but it will still be reported - * as 0. +/** @brief Get the current load as a ratio = achieved_flops / (core_current_speed * core_amount) + * + * You may also want to check simgrid::s4u::Host::get_load() that simply returns + * the achieved flop rate (in flops per seconds), ie the load that a new action arriving on + * that host would suffer. * - * So, use at your own risk. + * Please note that this function only returns an instantaneous load that may be deceiving + * in some scenarios. For example, imagine that an activity terminates at time t, and that + * another activity is created on the same host at the exact same timestamp. The load was + * never 0 on the simulated machine since the time did not advance between the two events. + * But still, if you call this function between the two events (in the simulator course), it + * returns 0 although there is no time (in the simulated time) where this value is valid. */ double HostLoad::get_current_load() { // We don't need to call update() here because it is called every time an action terminates or starts - // FIXME: Can this happen at the same time? stop -> call to getCurrentLoad, load = 0 -> next action starts? - return current_flops_ / static_cast(host_->get_speed() * host_->get_core_count()); + return current_flops_ / (host_->get_speed() * host_->get_core_count()); } /* @@ -116,7 +188,7 @@ void HostLoad::reset() idle_time_ = 0; computed_flops_ = 0; theor_max_flops_ = 0; - current_flops_ = host_->pimpl_cpu->get_constraint()->get_usage(); + current_flops_ = host_->get_load(); current_speed_ = host_->get_speed(); } } // namespace plugin @@ -127,119 +199,131 @@ using simgrid::plugin::HostLoad; /* **************************** events callback *************************** */ /* This callback is fired either when the host changes its state (on/off) or its speed * (because the user changed the pstate, or because of external trace events) */ -static void on_host_change(simgrid::s4u::Host& host) +static void on_host_change(simgrid::s4u::Host const& host) { - if (dynamic_cast(&host)) // Ignore virtual machines + if (dynamic_cast(&host)) // Ignore virtual machines return; host.extension()->update(); } -/* This callback is called when an action (computation, idle, ...) terminates */ -static void on_action_state_change(simgrid::surf::CpuAction* action, simgrid::kernel::resource::Action::State /*previous*/) -{ - for (simgrid::surf::Cpu* const& cpu : action->cpus()) { - simgrid::s4u::Host* host = cpu->get_host(); - - if (dynamic_cast(host)) // Ignore virtual machines - return; - - if (host != nullptr) { - host->extension()->update(); - } - } -} - /* **************************** Public interface *************************** */ -/** @ingroup plugin_load - * @brief Initializes the HostLoad plugin - * @details The HostLoad plugin provides an API to get the current load of each host. +/** @brief Initializes the HostLoad plugin + * @ingroup plugin_host_load */ void sg_host_load_plugin_init() { - if (HostLoad::EXTENSION_ID.valid()) + if (HostLoad::EXTENSION_ID.valid()) // Don't do the job twice return; + // First register our extension of Hosts properly HostLoad::EXTENSION_ID = simgrid::s4u::Host::extension_create(); - if (simgrid::s4u::Engine::is_initialized()) { // If not yet initialized, this would create a new instance - // which would cause seg faults... + // If SimGrid is already initialized, we need to attach an extension to each existing host + if (simgrid::s4u::Engine::is_initialized()) { simgrid::s4u::Engine* e = simgrid::s4u::Engine::get_instance(); for (auto& host : e->get_all_hosts()) { host->extension_set(new HostLoad(host)); } } - /* When attaching a callback into a signal, you can use a lambda as follows, or a regular function as done below */ - + // Make sure that every future host also gets an extension (in case the platform is not loaded yet) simgrid::s4u::Host::on_creation.connect([](simgrid::s4u::Host& host) { if (dynamic_cast(&host)) // Ignore virtual machines return; host.extension_set(new HostLoad(&host)); }); - simgrid::surf::CpuAction::on_state_change.connect(&on_action_state_change); + simgrid::s4u::Exec::on_start.connect([](simgrid::s4u::Actor const&, simgrid::s4u::Exec const& activity) { + if (activity.get_host_number() == 1) { // We only run on one host + simgrid::s4u::Host* host = activity.get_host(); + simgrid::s4u::VirtualMachine* vm = dynamic_cast(host); + if (vm != nullptr) + host = vm->get_pm(); + xbt_assert(host != nullptr); + host->extension()->add_activity(static_cast(activity.get_impl())); + host->extension()->update(); // If the system was idle until now, we need to update *before* + // this computation starts running so we can keep track of the + // idle time. (Communication operations don't trigger this hook!) + } + else { // This runs on multiple hosts + XBT_WARN("HostLoad plugin currently does not support executions on several hosts"); + } + }); + simgrid::s4u::Exec::on_completion.connect([](simgrid::s4u::Actor const&, simgrid::s4u::Exec const& activity) { + if (activity.get_host_number() == 1) { // We only run on one host + simgrid::s4u::Host* host = activity.get_host(); + simgrid::s4u::VirtualMachine* vm = dynamic_cast(host); + if (vm != nullptr) + host = vm->get_pm(); + xbt_assert(host != nullptr); + host->extension()->update(); + } + else { // This runs on multiple hosts + XBT_WARN("HostLoad plugin currently does not support executions on several hosts"); + } + }); simgrid::s4u::Host::on_state_change.connect(&on_host_change); simgrid::s4u::Host::on_speed_change.connect(&on_host_change); } -/** @brief Returns the current load of the host passed as argument - * - * See also @ref plugin_load +/** @brief Returns the current load of that host, as a ratio = achieved_flops / (core_current_speed * core_amount) + * @ingroup plugin_host_load */ double sg_host_get_current_load(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); return host->extension()->get_current_load(); } -/** @brief Returns the current load of the host passed as argument - * - * See also @ref plugin_load +/** @brief Returns the current load of that host + * @ingroup plugin_host_load */ double sg_host_get_avg_load(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); return host->extension()->get_average_load(); } /** @brief Returns the time this host was idle since the last reset - * - * See also @ref plugin_load + * @ingroup plugin_host_load */ double sg_host_get_idle_time(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); return host->extension()->get_idle_time(); } +/** @brief Returns the time this host was idle since the beginning of the simulation + * @ingroup plugin_host_load + */ double sg_host_get_total_idle_time(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); return host->extension()->get_total_idle_time(); } +/** @brief Returns the amount of flops computed by that host since the last reset + * @ingroup plugin_host_load + */ double sg_host_get_computed_flops(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); return host->extension()->get_computed_flops(); } +/** @brief Resets the idle time and flops amount of that host + * @ingroup plugin_host_load + */ void sg_host_load_reset(sg_host_t host) { - xbt_assert(HostLoad::EXTENSION_ID.valid(), - "The Load plugin is not active. Please call sg_host_load_plugin_init() during initialization."); + xbt_assert(HostLoad::EXTENSION_ID.valid(), "Please sg_host_load_plugin_init() to initialize this plugin."); host->extension()->reset(); }