*/
public native double getConsumedEnergy();
- /** Returns the current load of the host */
+ /** Returns the current load of the host, as a ratio = achieved_flops / (core_current_speed * core_amount)
+ *
+ * See simgrid::plugin::HostLoad::get_current_load() for the full documentation.
+ */
public native double getCurrentLoad();
- /** Returns the number of flops computed of the host */
+ /** Returns the number of flops computed of the host since the beginning of the simulation */
public native double getComputedFlops();
- /** Returns the average load of the host */
+ /** Returns the average load of the host as a ratio since the beginning of the simulation*/
public native double getAvgLoad();
+
/** Returns the current pstate */
public native int getPstate();
/** Changes the current pstate */
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();
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()
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)
{
