-/* 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. */
explicit HostLoad(simgrid::s4u::Host&& ptr) = delete;
double get_current_load();
+ /** 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_; }
- double get_idle_time() { update(); return idle_time_; } /** Return idle time since last reset */
- double get_total_idle_time() { update(); return total_idle_time_; } /** Return idle time over the whole simulation */
+ /** 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();
{
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 current_iter = iter;
+ ++iter;
+
+ if (activity->surf_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 = activity->surf_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_;
-
if (current_flops_ == 0) {
idle_time_ += (now - last_updated_);
total_idle_time_ += (now - last_updated_);
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<double>(host_->get_speed() * host_->get_core_count());
}
/* **************************** Public interface *************************** */
-/** @ingroup plugin_load
- * @brief Initializes the HostLoad plugin
+/** @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::ExecImplPtr activity){
+ if (activity->host_ != nullptr) { // We only run on one host
+ simgrid::s4u::Host* host = activity->host_;
+ if (dynamic_cast<simgrid::s4u::VirtualMachine*>(activity->host_))
+ host = dynamic_cast<simgrid::s4u::VirtualMachine*>(activity->host_)->get_pm();
+
+ 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::ExecImplPtr activity){
+ if (activity->host_ != nullptr) { // We only run on one host
+ simgrid::s4u::Host* host = activity->host_;
+ if (dynamic_cast<simgrid::s4u::VirtualMachine*>(activity->host_))
+ host = dynamic_cast<simgrid::s4u::VirtualMachine*>(activity->host_)->get_pm();
+
+ 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)
{