From 56ba73d27fc159241b1a6208301f8ff51ef69dc8 Mon Sep 17 00:00:00 2001 From: Martin Quinson Date: Wed, 17 Jan 2018 12:19:30 +0100 Subject: [PATCH] fix sg_host_get_current_consumption() to do the same as C++ --- src/surf/plugins/host_energy.cpp | 85 ++++++++++++++++++-------------- 1 file changed, 48 insertions(+), 37 deletions(-) diff --git a/src/surf/plugins/host_energy.cpp b/src/surf/plugins/host_energy.cpp index 2a0947f494..7074846e53 100644 --- a/src/surf/plugins/host_energy.cpp +++ b/src/surf/plugins/host_energy.cpp @@ -128,6 +128,7 @@ public: explicit HostEnergy(simgrid::s4u::Host* ptr); ~HostEnergy(); + double getCurrentWattsValue(); double getCurrentWattsValue(double cpu_load); double getConsumedEnergy(); double getWattMinAt(int pstate); @@ -159,44 +160,11 @@ void HostEnergy::update() { double start_time = this->last_updated; double finish_time = surf_get_clock(); - double current_speed = host->getSpeed(); if (start_time < finish_time) { - double cpu_load; - // We may have start == finish if the past consumption was updated since the simcall was started - // for example if 2 actors requested to update the same host's consumption in a given scheduling round. - // - // Even in this case, we need to save the pstate for the next call (after this big if), - // which may have changed since that recent update. - - if (current_speed <= 0) - // Some users declare a pstate of speed 0 flops (e.g., to model boot time). - // We consider that the machine is then fully loaded. That's arbitrary but it avoids a NaN - cpu_load = 1; - else - cpu_load = host->pimpl_cpu->constraint()->get_usage() / current_speed; - - /** Divide by the number of cores here **/ - cpu_load /= host->pimpl_cpu->coreCount(); - - if (cpu_load > 1) // A machine with a load > 1 consumes as much as a fully loaded machine, not more - cpu_load = 1; - - /* The problem with this model is that the load is always 0 or 1, never something less. - * Another possibility could be to model the total energy as - * - * X/(X+Y)*W_idle + Y/(X+Y)*W_burn - * - * where X is the amount of idling cores, and Y the amount of computing cores. - */ - double previous_energy = this->total_energy; - double instantaneous_consumption; - if (this->pstate == pstate_off) // The host was off at the beginning of this time interval - instantaneous_consumption = this->watts_off; - else - instantaneous_consumption = this->getCurrentWattsValue(cpu_load); + double instantaneous_consumption = this->getCurrentWattsValue(); double energy_this_step = instantaneous_consumption * (finish_time - start_time); @@ -245,7 +213,51 @@ double HostEnergy::getWattMaxAt(int pstate) return power_range_watts_list[pstate].max; } -/** @brief Computes the power consumed by the host according to the current pstate and processor load */ +/** @brief Computes the power consumed by the host according to the current situation + * + * - If the host is off, that's the watts_off value + * - if it's on, take the current pstate and the current processor load into account */ +double HostEnergy::getCurrentWattsValue() +{ + if (this->pstate == pstate_off) // The host is off (or was off at the beginning of this time interval) + return this->watts_off; + + double current_speed = host->getSpeed(); + + double cpu_load; + // We may have start == finish if the past consumption was updated since the simcall was started + // for example if 2 actors requested to update the same host's consumption in a given scheduling round. + // + // Even in this case, we need to save the pstate for the next call (after this big if), + // which may have changed since that recent update. + + if (current_speed <= 0) + // Some users declare a pstate of speed 0 flops (e.g., to model boot time). + // We consider that the machine is then fully loaded. That's arbitrary but it avoids a NaN + cpu_load = 1; + else + cpu_load = host->pimpl_cpu->constraint()->get_usage() / current_speed; + + /** Divide by the number of cores here **/ + cpu_load /= host->pimpl_cpu->coreCount(); + + if (cpu_load > 1) // A machine with a load > 1 consumes as much as a fully loaded machine, not more + cpu_load = 1; + + /* The problem with this model is that the load is always 0 or 1, never something less. + * Another possibility could be to model the total energy as + * + * X/(X+Y)*W_idle + Y/(X+Y)*W_burn + * + * where X is the amount of idling cores, and Y the amount of computing cores. + */ + return getCurrentWattsValue(cpu_load); +} + +/** @brief Computes the power that the host would consume at the provided processor load + * + * Whether the host is ON or OFF is not taken into account. + */ double HostEnergy::getCurrentWattsValue(double cpu_load) { xbt_assert(not power_range_watts_list.empty(), "No power range properties specified for host %s", host->getCname()); @@ -517,7 +529,6 @@ double sg_host_get_current_consumption(sg_host_t host) { xbt_assert(HostEnergy::EXTENSION_ID.valid(), "The Energy plugin is not active. Please call sg_energy_plugin_init() during initialization."); - double cpu_load = host->pimpl_cpu->constraint()->get_usage() / host->getSpeed(); - return host->extension()->getCurrentWattsValue(cpu_load); + return host->extension()->getCurrentWattsValue(); } } -- 2.20.1