-/* 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/s4u.hpp>
#include "simgrid/plugins/load.h"
+#include "src/include/surf/surf.hpp"
+#include "src/kernel/activity/ExecImpl.hpp"
#include "src/plugins/vm/VirtualMachineImpl.hpp"
+#include <simgrid/s4u.hpp>
+
+SIMGRID_REGISTER_PLUGIN(host_load, "Cpu load", &sg_host_load_plugin_init)
/** @addtogroup plugin_load
namespace simgrid {
namespace plugin {
+static const double activity_uninitialized_remaining_cost = -1;
+
class HostLoad {
public:
static simgrid::xbt::Extension<simgrid::s4u::Host, HostLoad> EXTENSION_ID;
: host_(ptr)
, last_updated_(surf_get_clock())
, last_reset_(surf_get_clock())
- , current_speed_(host_->getSpeed())
+ , current_speed_(host_->get_speed())
, current_flops_(host_->pimpl_cpu->get_constraint()->get_usage())
, theor_max_flops_(0)
- , was_prev_idle_(current_flops_ == 0)
{
}
~HostLoad() = default;
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 */
+ /** 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::ExecImplPtr activity);
void reset();
private:
simgrid::s4u::Host* host_ = nullptr;
+ /* Stores all currently ongoing activities (computations) on this machine */
+ std::map<simgrid::kernel::activity::ExecImplPtr, /* cost still remaining*/double> current_activities;
double last_updated_ = 0;
double last_reset_ = 0;
/**
- * current_speed each core is running at right now
+ * current_speed each core is running at; we need to store this as the speed
+ * will already have changed once we get notified
*/
double current_speed_ = 0;
/**
double current_flops_ = 0;
double computed_flops_ = 0;
double idle_time_ = 0;
+ double total_idle_time_ = 0; /* This gets never reset */
double theor_max_flops_ = 0;
- bool was_prev_idle_ = true; /* A host is idle at the beginning */
};
simgrid::xbt::Extension<simgrid::s4u::Host, HostLoad> HostLoad::EXTENSION_ID;
+void HostLoad::add_activity(simgrid::kernel::activity::ExecImplPtr activity)
+{
+ current_activities.insert({activity, activity_uninitialized_remaining_cost});
+}
+
void HostLoad::update()
{
double now = surf_get_clock();
- /* Current flop per second computed by the cpu; current_flops = k * pstate_speed_in_flops, k \in {0, 1, ..., cores}
- * number of active cores */
- current_flops_ = host_->pimpl_cpu->get_constraint()->get_usage();
+ // 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);
+ }
+ }
- /* flops == pstate_speed * cores_being_currently_used */
- computed_flops_ += (now - last_updated_) * current_flops_;
+ /* 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();
- if (was_prev_idle_) {
+ if (current_flops_ == 0) {
idle_time_ += (now - last_updated_);
+ total_idle_time_ += (now - last_updated_);
+ XBT_DEBUG("[%s]: Currently idle -> Added %f seconds to idle time (totaling %fs)", host_->get_cname(), (now - last_updated_), idle_time_);
}
theor_max_flops_ += current_speed_ * host_->get_core_count() * (now - last_updated_);
- current_speed_ = host_->getSpeed();
+ current_speed_ = host_->get_speed();
last_updated_ = now;
- was_prev_idle_ = (current_flops_ == 0);
}
-/**
- * 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)
*
- * So, use at your own risk.
+ * 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.
+ *
+ * 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<double>(host_->getSpeed() * host_->get_core_count());
+ return current_flops_ / (host_->get_speed() * host_->get_core_count());
}
/*
computed_flops_ = 0;
theor_max_flops_ = 0;
current_flops_ = host_->pimpl_cpu->get_constraint()->get_usage();
- current_speed_ = host_->getSpeed();
- was_prev_idle_ = (current_flops_ == 0);
+ current_speed_ = host_->get_speed();
}
} // namespace plugin
} // namespace simgrid
/* **************************** 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<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
+ if (dynamic_cast<simgrid::s4u::VirtualMachine const*>(&host)) // Ignore virtual machines
return;
host.extension<HostLoad>()->update();
}
-/* This callback is called when an action (computation, idle, ...) terminates */
-static void on_action_state_change(simgrid::surf::CpuAction* action)
-{
- for (simgrid::surf::Cpu* const& cpu : action->cpus()) {
- simgrid::s4u::Host* host = cpu->get_host();
-
- if (dynamic_cast<simgrid::s4u::VirtualMachine*>(host)) // Ignore virtual machines
- return;
-
- if (host != nullptr) {
- host->extension<HostLoad>()->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
+ * @details The HostLoad plugin provides an API to get the current load of each host.
*/
void sg_host_load_plugin_init()
{
host.extension_set(new HostLoad(&host));
});
- simgrid::surf::CpuAction::on_state_change.connect(&on_action_state_change);
+ simgrid::kernel::activity::ExecImpl::on_creation.connect([](simgrid::kernel::activity::ExecImpl& 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<simgrid::s4u::VirtualMachine*>(host);
+ if (vm != nullptr)
+ host = vm->get_pm();
+ xbt_assert(host != nullptr);
+ host->extension<HostLoad>()->add_activity(&activity);
+ host->extension<HostLoad>()->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_DEBUG("HostLoad plugin currently does not support executions on several hosts");
+ }
+ });
+ simgrid::kernel::activity::ExecImpl::on_completion.connect([](simgrid::kernel::activity::ExecImpl 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<simgrid::s4u::VirtualMachine*>(host);
+ if (vm != nullptr)
+ host = vm->get_pm();
+ xbt_assert(host != nullptr);
+ host->extension<HostLoad>()->update();
+ }
+ else { // This runs on multiple hosts
+ XBT_DEBUG("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
+/** @brief Returns the current load of that host, as a ratio = achieved_flops / (core_current_speed * core_amount)
*
- * See also @ref plugin_load
+ * See simgrid::plugin::HostLoad::get_current_load() for the full documentation.
*/
double sg_host_get_current_load(sg_host_t host)
{
return host->extension<HostLoad>()->get_idle_time();
}
+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.");
+
+ return host->extension<HostLoad>()->get_total_idle_time();
+}
+
double sg_host_get_computed_flops(sg_host_t host)
{
xbt_assert(HostLoad::EXTENSION_ID.valid(),
