From 717a002520be19ebeca1d096aa67c3175d15a3ba Mon Sep 17 00:00:00 2001 From: clement-dell Date: Tue, 30 Jul 2019 16:04:13 +0200 Subject: [PATCH] Rework host_energy plugin Related to issue #189 --- include/simgrid/plugins/energy.h | 2 + src/plugins/host_energy.cpp | 204 +++++++++++++++---------------- 2 files changed, 98 insertions(+), 108 deletions(-) diff --git a/include/simgrid/plugins/energy.h b/include/simgrid/plugins/energy.h index cfd6840bb9..c8ad3489de 100644 --- a/include/simgrid/plugins/energy.h +++ b/include/simgrid/plugins/energy.h @@ -17,6 +17,7 @@ XBT_PUBLIC double sg_host_get_consumed_energy(sg_host_t host); XBT_PUBLIC double sg_host_get_idle_consumption(sg_host_t host); XBT_PUBLIC double sg_host_get_wattmin_at(sg_host_t host, int pstate); XBT_PUBLIC double sg_host_get_wattmax_at(sg_host_t host, int pstate); +XBT_PUBLIC double sg_host_get_power_range_slope_at(sg_host_t host, int pstate); XBT_PUBLIC double sg_host_get_current_consumption(sg_host_t host); XBT_PUBLIC void sg_link_energy_plugin_init(); @@ -28,6 +29,7 @@ XBT_PUBLIC int sg_link_energy_is_inited(); #define MSG_host_get_consumed_energy(host) sg_host_get_consumed_energy(host) #define MSG_host_get_wattmin_at(host,pstate) sg_host_get_wattmin_at(host,pstate) #define MSG_host_get_wattmax_at(host,pstate) sg_host_get_wattmax_at(host,pstate) +#define MSG_host_get_power_range_slope_at(host,pstate) sg_host_get_power_range_slope_at(host,pstate) #define MSG_host_get_current_consumption(host) sg_host_get_current_consumption(host) SG_END_DECL() diff --git a/src/plugins/host_energy.cpp b/src/plugins/host_energy.cpp index 2dd43f54f3..dd95c9f5c5 100644 --- a/src/plugins/host_energy.cpp +++ b/src/plugins/host_energy.cpp @@ -30,57 +30,44 @@ abnormality when all the cores are idle. The full details are in As a result, our energy model takes 4 parameters: - @b Idle: instantaneous consumption (in Watt) when your host is up and running, but without anything to do. - - @b OneCore: instantaneous consumption (in Watt) when only one core is active, at 100%. + - @b Epsilon: instantaneous consumption (in Watt) when all cores are at 0 or epsilon%, but not in Idle state. - @b AllCores: instantaneous consumption (in Watt) when all cores of the host are at 100%. - @b Off: instantaneous consumption (in Watt) when the host is turned off. Here is an example of XML declaration: @code{.xml} - + @endcode -This example gives the following parameters: @b Off is 10 Watts; @b Idle is 100 Watts; @b OneCore is 120 Watts and @b +Please note that the 'Epsilon' parameter can be omitted in the XML declaration. In that case, the value of 'Epsilon' will +be the same as 'Idle'. + + +This example gives the following parameters: @b Off is 10 Watts; @b Idle is 100 Watts; @b Epsilon is 120 Watts and @b AllCores is 200 Watts. This is enough to compute the consumption as a function of the amount of loaded cores: - - - - + + + + +
@#Cores loadedConsumptionExplanation
0 100 WattsIdle value
1 120 WattsOneCore value
2 147 Wattslinear extrapolation between OneCore and AllCores
3 173 Wattslinear extrapolation between OneCore and AllCores
0 (idle) 100 WattsIdle value
0 (not idle) 120 WattsEpsilon value
1 140 Wattslinear extrapolation between Epsilon and AllCores
2 160 Wattslinear extrapolation between Epsilon and AllCores
3 180 Wattslinear extrapolation between Epsilon and AllCores
4 200 WattsAllCores value
-### What if a given core is only at load 50%? - -This is impossible in SimGrid because we recompute everything each time that the CPU starts or stops doing something. -So if a core is at load 50% over a period, it means that it is at load 100% half of the time and at load 0% the rest of -the time, and our model holds. - -### What if the host has only one core? - -In this case, the parameters @b OneCore and @b AllCores are obviously the same. -Actually, SimGrid expect an energetic profile formatted as 'Idle:Running' for mono-cores hosts. -If you insist on passing 3 parameters in this case, then you must have the same value for @b OneCore and @b AllCores. - -@code{.xml} - - - - -@endcode ### How does DVFS interact with the host energy model? If your host has several DVFS levels (several pstates), then you should give the energetic profile of each pstate level: @code{.xml} - + @@ -88,7 +75,7 @@ If your host has several DVFS levels (several pstates), then you should give the This encodes the following values - + @@ -117,10 +104,11 @@ namespace plugin { class PowerRange { public: double idle_; - double min_; + double epsilon_; double max_; + double slope_; - PowerRange(double idle, double min, double max) : idle_(idle), min_(min), max_(max) {} + PowerRange(double idle, double epsilon, double max) : idle_(idle), epsilon_(epsilon), max_(max), slope_(max-epsilon) {} }; class HostEnergy { @@ -137,12 +125,13 @@ public: double get_idle_consumption(); double get_watt_min_at(int pstate); double get_watt_max_at(int pstate); + double get_power_range_slope_at(int pstate); void update(); private: void init_watts_range_list(); simgrid::s4u::Host* host_ = nullptr; - /*< List of (min_power,max_power) pairs corresponding to each cpu pstate */ + /*< List of (idle_power, epsilon_power, max_power) tuple corresponding to each cpu pstate */ std::vector power_range_watts_list_; /* We need to keep track of what pstate has been used, as we will sometimes be notified only *after* a pstate has been @@ -177,16 +166,16 @@ void HostEnergy::update() if (start_time < finish_time) { double previous_energy = this->total_energy_; - double instantaneous_consumption = this->get_current_watts_value(); + double instantaneous_power_consumption = this->get_current_watts_value(); - double energy_this_step = instantaneous_consumption * (finish_time - start_time); + double energy_this_step = instantaneous_power_consumption * (finish_time - start_time); // TODO Trace: Trace energy_this_step from start_time to finish_time in host->getName() this->total_energy_ = previous_energy + energy_this_step; this->last_updated_ = finish_time; - XBT_DEBUG("[update_energy of %s] period=[%.8f-%.8f]; current speed=%.2E flop/s (pstate %i); total consumption before: consumption change: %.8f J -> added now: %.8f J", + XBT_DEBUG("[update_energy of %s] period=[%.8f-%.8f]; current speed=%.2E flop/s (pstate %i); total consumption before: %.8f J -> added now: %.8f J", host_->get_cname(), start_time, finish_time, host_->pimpl_cpu->get_pstate_peak_speed(this->pstate_), this->pstate_, previous_energy, energy_this_step); } @@ -225,7 +214,7 @@ double HostEnergy::get_watt_min_at(int pstate) { xbt_assert(not power_range_watts_list_.empty(), "No power range properties specified for host %s", host_->get_cname()); - return power_range_watts_list_[pstate].min_; + return power_range_watts_list_[pstate].epsilon_; } double HostEnergy::get_watt_max_at(int pstate) @@ -235,6 +224,13 @@ double HostEnergy::get_watt_max_at(int pstate) return power_range_watts_list_[pstate].max_; } +double HostEnergy::get_power_range_slope_at(int pstate) +{ + xbt_assert(not power_range_watts_list_.empty(), "No power range properties specified for host %s", + host_->get_cname()); + return power_range_watts_list_[pstate].slope_; +} + /** @brief Computes the power consumed by the host according to the current situation * * - If the host is off, that's the watts_off value @@ -255,7 +251,7 @@ double HostEnergy::get_current_watts_value() else { cpu_load = host_->pimpl_cpu->get_constraint()->get_usage() / current_speed; - /** Divide by the number of cores here **/ + /** Divide by the number of cores here to have a value between 0 and 1 **/ cpu_load /= host_->pimpl_cpu->get_core_count(); if (cpu_load > 1) // A machine with a load > 1 consumes as much as a fully loaded machine, not more @@ -264,12 +260,16 @@ double HostEnergy::get_current_watts_value() host_was_used_ = true; } - /* The problem with this model is that the load is always 0 or 1, never something less. + /* @mquinson: 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. + * + * @Mommessc: I do not think the load is always 0 or 1 anymore. + * Moreover, it is not quite clear how the regular model of power consumption (P = Pstatic + load * Pdynamic) + * is impacted if we separate the number of idle and working cores. */ return get_current_watts_value(cpu_load); } @@ -288,44 +288,29 @@ double HostEnergy::get_current_watts_value(double cpu_load) return watts_off_; } - /* min_power corresponds to the power consumed when only one core is active */ - /* max_power is the power consumed at 100% cpu load */ - auto range = power_range_watts_list_.at(this->pstate_); + PowerRange power_range = power_range_watts_list_.at(this->pstate_); double current_power; - double min_power; - double max_power; - double power_slope; - - if (cpu_load > 0) { /* Something is going on, the machine is not idle */ - min_power = range.min_; - max_power = range.max_; - - /** - * The min_power states how much we consume when only one single - * core is working. This means that when cpu_load == 1/coreCount, then - * current_power == min_power. - * - * The maximum must be reached when all cores are working (but 1 core was - * already accounted for by min_power) - * i.e., we need min_power + (maxCpuLoad-1/coreCount)*power_slope == max_power - * (maxCpuLoad is by definition 1) - */ - int coreCount = host_->get_core_count(); - double coreReciprocal = 1.0 / coreCount; - if (coreCount > 1) - power_slope = (max_power - min_power) / (1 - coreReciprocal); - else - power_slope = 0; // Should be 0, since max_power == min_power (in this case) - - current_power = min_power + (cpu_load - coreReciprocal) * power_slope; - } else { /* Our machine is idle, take the dedicated value! */ - min_power = 0; - max_power = 0; - power_slope = 0; - current_power = range.idle_; + + if (cpu_load > 0) + { + /** + * Something is going on, the host is not idle. + * + * The power consumption follows the regular model: + * P(cpu_load) = Pstatic + Pdynamic * cpu_load + * where Pstatic = power_range.epsilon_ and Pdynamic = power_range.slope_ + * and the cpu_load is a value between 0 and 1. + */ + current_power = power_range.epsilon_ + cpu_load * power_range.slope_; + } + else + { + /* The host is idle, take the dedicated value! */ + current_power = power_range.idle_; } - XBT_DEBUG("[get_current_watts] pstate=%i, min_power=%f, max_power=%f, slope=%f", this->pstate_, min_power, max_power, power_slope); + XBT_DEBUG("[get_current_watts] pstate=%i, epsilon_power=%f, max_power=%f, slope=%f", this->pstate_, power_range.epsilon_, + power_range.max_, power_range.slope_); XBT_DEBUG("[get_current_watts] Current power (watts) = %f, load = %f", current_power, cpu_load); return current_power; @@ -347,52 +332,47 @@ void HostEnergy::init_watts_range_list() std::vector all_power_values; boost::split(all_power_values, all_power_values_str, boost::is_any_of(",")); - XBT_DEBUG("%s: profile: %s, cores: %d", host_->get_cname(), all_power_values_str, host_->get_core_count()); + XBT_DEBUG("%s: power properties: %s", host_->get_cname(), all_power_values_str); int i = 0; for (auto const& current_power_values_str : all_power_values) { - /* retrieve the power values associated with the current pstate */ + /* retrieve the power values associated with the pstate i */ std::vector current_power_values; boost::split(current_power_values, current_power_values_str, boost::is_any_of(":")); - if (host_->get_core_count() == 1) { - xbt_assert(current_power_values.size() == 2 || current_power_values.size() == 3, - "Power properties incorrectly defined for host %s." - "It should be 'Idle:FullSpeed' power values because you have one core only.", - host_->get_cname()); - if (current_power_values.size() == 2) { - // In this case, 1core == AllCores - current_power_values.push_back(current_power_values.at(1)); - } else { // size == 3 - current_power_values[1] = current_power_values.at(2); - current_power_values[2] = current_power_values.at(2); - static bool displayed_warning = false; - if (not displayed_warning) { // Otherwise we get in the worst case no_pstate*no_hosts warnings - XBT_WARN("Host %s is a single-core machine and part of the power profile is '%s'" - ", which is in the 'Idle:OneCore:AllCores' format." - " Here, only the value for 'AllCores' is used.", host_->get_cname(), current_power_values_str.c_str()); - displayed_warning = true; - } - } - } else { - xbt_assert(current_power_values.size() == 3, - "Power properties incorrectly defined for host %s." - "It should be 'Idle:OneCore:AllCores' power values because you have more than one core.", - host_->get_cname()); + + xbt_assert(current_power_values.size() == 2 || current_power_values.size() == 3, + "Power properties incorrectly defined for host %s." + "It should be 'Idle:AllCores' (or 'Idle:Epsilon:AllCores') power values.", + host_->get_cname()); + + double idle_power; + double epsilon_power; + double max_power; + + char* msg_idle = bprintf("Invalid Idle value for pstate %d on host %s: %%s", i, host_->get_cname()); + char* msg_epsilon = bprintf("Invalid Epsilon value for pstate %d on host %s: %%s", i, host_->get_cname()); + char* msg_max = bprintf("Invalid AllCores value for pstate %d on host %s: %%s", i, host_->get_cname()); + + idle_power = xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle); + if (current_power_values.size() == 2) // Case: Idle:AllCores + { + epsilon_power = xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle); + max_power = xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_max); } + else // Case: Idle:Epsilon:AllCores + { + epsilon_power = xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_epsilon); + max_power = xbt_str_parse_double((current_power_values.at(2)).c_str(), msg_max); + } + + XBT_DEBUG("Creating PowerRange for host %s. Idle:%f, Epsilon:%f, AllCores:%f.", host_->get_cname(), idle_power, epsilon_power, max_power); - /* min_power corresponds to the idle power (cpu load = 0) */ - /* max_power is the power consumed at 100% cpu load */ - char* msg_idle = bprintf("Invalid idle value for pstate %d on host %s: %%s", i, host_->get_cname()); - char* msg_min = bprintf("Invalid OneCore value for pstate %d on host %s: %%s", i, host_->get_cname()); - char* msg_max = bprintf("Invalid AllCores value for pstate %d on host %s: %%s", i, host_->get_cname()); - PowerRange range(xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle), - xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_min), - xbt_str_parse_double((current_power_values.at(2)).c_str(), msg_max)); + PowerRange range(idle_power, epsilon_power, max_power); power_range_watts_list_.push_back(range); xbt_free(msg_idle); - xbt_free(msg_min); + xbt_free(msg_epsilon); xbt_free(msg_max); - i++; + ++i; } } } // namespace plugin @@ -569,7 +549,15 @@ double sg_host_get_wattmax_at(sg_host_t host, int pstate) "The Energy plugin is not active. Please call sg_host_energy_plugin_init() during initialization."); return host->extension()->get_watt_max_at(pstate); } - +/** @ingroup plugin_energy + * @brief Returns the power slope at the given pstate + */ +double sg_host_get_power_range_slope_at(sg_host_t host, int pstate) +{ + xbt_assert(HostEnergy::EXTENSION_ID.valid(), + "The Energy plugin is not active. Please call sg_host_energy_plugin_init() during initialization."); + return host->extension()->get_power_range_slope_at(pstate); +} /** @ingroup plugin_energy * @brief Returns the current consumption of the host */ -- 2.20.1
pstatePerformanceIdleOneCoreAllCores
pstatePerformanceIdleEpsilonAllCores
0100 Mflop/s95 Watts120 Watts200 Watts
150 Mflop/s93 Watts115 Watts170 Watts
220 Mflop/s90 Watts110 Watts150 Watts