1 /* Copyright (c) 2010-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include <simgrid/Exception.hpp>
7 #include <simgrid/plugins/energy.h>
8 #include <simgrid/s4u/Engine.hpp>
9 #include <simgrid/s4u/Exec.hpp>
10 #include <simgrid/s4u/Host.hpp>
11 #include <simgrid/s4u/VirtualMachine.hpp>
12 #include <simgrid/simix.hpp>
14 #include "src/kernel/resource/CpuImpl.hpp"
16 #include <boost/algorithm/string/classification.hpp>
17 #include <boost/algorithm/string/split.hpp>
19 SIMGRID_REGISTER_PLUGIN(host_energy, "Cpu energy consumption.", &sg_host_energy_plugin_init)
21 /** @defgroup plugin_host_energy plugin_host_energy Plugin Host Energy
25 This is the energy plugin, enabling to account not only for computation time, but also for the dissipated energy in the
27 To activate this plugin, first call :cpp:func:`sg_host_energy_plugin_init()` before your loading your platform, and
28 then use :cpp:func:`sg_host_get_consumed_energy()` to retrieve the consumption of a given host.
30 When the host is on, this energy consumption naturally depends on both the current CPU load and the host energy profile.
31 According to our measurements, the consumption is somehow linear in the amount of cores at full speed, with an
32 abnormality when all the cores are idle. The full details are in `our scientific paper
33 <https://hal.inria.fr/hal-01523608>`_ on that topic.
35 As a result, our energy model takes 4 parameters:
37 - ``Idle`` wattage (i.e., instantaneous consumption in Watt) when your host is up and running, but without anything to
39 - ``Epsilon`` wattage when all cores are at 0 or epsilon%, but not in Idle state.
40 - ``AllCores`` wattage when all cores of the host are at 100%.
41 - ``Off`` wattage when the host is turned off.
43 Here is an example of XML declaration:
47 <host id="HostA" speed="100.0Mf" core="4">
48 <prop id="wattage_per_state" value="100.0:120.0:200.0" />
49 <prop id="wattage_off" value="10" />
52 If only two values are given, ``Idle`` is used for the missing ``Epsilon`` value.
54 This example gives the following parameters: ``Off`` is 10 Watts; ``Idle`` is 100 Watts; ``Epsilon`` is 120 Watts and
55 ``AllCores`` is 200 Watts.
56 This is enough to compute the wattage as a function of the amount of loaded cores:
61 <tr><th>#Cores loaded</th><th>Wattage</th><th>Explanation</th></tr>
62 <tr><td>0 (idle)</td><td> 100 Watts </td><td> Idle value</td></tr>
63 <tr><td>0 (not idle)</td><td> 120 Watts</td><td> Epsilon value</td></tr>
64 <tr><td>1</td><td> 140 Watts</td><td> Linear extrapolation between Epsilon and AllCores</td></tr>
65 <tr><td>2</td><td> 160 Watts</td><td> Linear extrapolation between Epsilon and AllCores</td></tr>
66 <tr><td>3</td><td> 180 Watts</td><td> Linear extrapolation between Epsilon and AllCores</td></tr>
67 <tr><td>4</td><td> 200 Watts</td><td> AllCores value</td></tr>
73 <h4>How does DVFS interact with the host energy model?</h4>
75 If your host has several DVFS levels (several pstates), then you should give the energetic profile of each pstate level:
79 <host id="HostC" speed="100.0Mf,50.0Mf,20.0Mf" core="4">
80 <prop id="wattage_per_state"
81 value="95.0:120.0:200.0, 93.0:115.0:170.0, 90.0:110.0:150.0" />
82 <prop id="wattage_off" value="10" />
85 This encodes the following values:
90 <tr><th>pstate</th><th>Performance</th><th>Idle</th><th>Epsilon</th><th>AllCores</th></tr>
91 <tr><td>0</td><td>100 Mflop/s</td><td>95 Watts</td><td>120 Watts</td><td>200 Watts</td></tr>
92 <tr><td>1</td><td>50 Mflop/s</td><td>93 Watts</td><td>115 Watts</td><td>170 Watts</td></tr>
93 <tr><td>2</td><td>20 Mflop/s</td><td>90 Watts</td><td>110 Watts</td><td>150 Watts</td></tr>
96 To change the pstate of a given CPU, use the following functions:
97 :cpp:func:`MSG_host_get_nb_pstates()`, :cpp:func:`simgrid::s4u::Host::set_pstate()`,
98 :cpp:func:`MSG_host_get_power_peak_at()`.
102 <h4>How accurate are these models?</h4>
104 This model cannot be more accurate than your instantiation: with the default values, your result will not be accurate at
105 all. You can still get accurate energy prediction, provided that you carefully instantiate the model.
106 The first step is to ensure that your timing prediction match perfectly. But this is only the first step of the path,
107 and you really want to read `this paper <https://hal.inria.fr/hal-01523608>`_ to see all what you need to do
108 before you can get accurate energy predictions.
113 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(host_energy, kernel, "Logging specific to the host energy plugin");
115 // Forwards declaration needed to make this function a friend (because friends have external linkage by default)
116 static void on_simulation_end();
128 PowerRange(double idle, double epsilon, double max) : idle_(idle), epsilon_(epsilon), max_(max), slope_(max-epsilon) {}
132 simgrid::s4u::Host* host_ = nullptr;
133 /*< List of (idle_power, epsilon_power, max_power) tuple corresponding to each cpu pstate */
134 std::vector<PowerRange> power_range_watts_list_;
135 bool has_pstate_power_values_ = false; /*< Whether power consumption values were provided for all pstates */
137 /* We need to keep track of what pstate has been used, as we will sometimes be notified only *after* a pstate has been
138 * used (but we need to update the energy consumption with the old pstate!)
141 const int pstate_off_ = -1;
142 double watts_off_ = 0.0; /*< Consumption when the machine is turned off (shutdown) */
143 double total_energy_ = 0.0; /*< Total energy consumed by the host */
144 double last_updated_ = simgrid::s4u::Engine::get_clock(); /*< Timestamp of the last energy update event*/
146 /* Only used to split total energy into unused/used hosts.
147 * If you want to get this info for something else, rather use the host_load plugin
149 bool host_was_used_ = false;
151 void init_watts_range_list();
152 friend void ::on_simulation_end(); // For access to host_was_used_
155 static simgrid::xbt::Extension<simgrid::s4u::Host, HostEnergy> EXTENSION_ID;
157 explicit HostEnergy(simgrid::s4u::Host* ptr);
160 bool has_pstate_power_values() const;
162 double get_current_watts_value();
163 double get_current_watts_value(double cpu_load) const;
164 double get_consumed_energy();
165 double get_watt_idle_at(int pstate) const;
166 double get_watt_min_at(int pstate) const;
167 double get_watt_max_at(int pstate) const;
168 double get_power_range_slope_at(int pstate) const;
169 double get_last_update_time() const { return last_updated_; }
173 simgrid::xbt::Extension<simgrid::s4u::Host, HostEnergy> HostEnergy::EXTENSION_ID;
175 /* Returns whether power consumption values were provided for all pstates. */
176 bool HostEnergy::has_pstate_power_values() const {
177 return has_pstate_power_values_;
180 /* Computes the consumption so far. Called lazily on need. */
181 void HostEnergy::update()
183 double start_time = last_updated_;
184 double finish_time = simgrid::s4u::Engine::get_clock();
186 // We may have start == finish if the past consumption was updated since the simcall was started
187 // for example if 2 actors requested to update the same host's consumption in a given scheduling round.
189 // Even in this case, we need to save the pstate for the next call (after this if),
190 // which may have changed since that recent update.
191 if (start_time < finish_time) {
192 double previous_energy = total_energy_;
194 double instantaneous_power_consumption = this->get_current_watts_value();
196 double energy_this_step = instantaneous_power_consumption * (finish_time - start_time);
198 // TODO Trace: Trace energy_this_step from start_time to finish_time in host->getName()
200 total_energy_ = previous_energy + energy_this_step;
201 last_updated_ = finish_time;
203 XBT_DEBUG("[update_energy of %s] period=[%.8f-%.8f]; current speed=%.2E flop/s (pstate %i); total consumption "
204 "before: %.8f J -> added now: %.8f J",
205 host_->get_cname(), start_time, finish_time, host_->get_pstate_speed(pstate_), pstate_, previous_energy,
209 /* Save data for the upcoming time interval: whether it's on/off and the pstate if it's on */
210 pstate_ = host_->is_on() ? host_->get_pstate() : pstate_off_;
213 HostEnergy::HostEnergy(simgrid::s4u::Host* ptr) : host_(ptr)
215 init_watts_range_list();
217 const char* off_power_str = host_->get_property("wattage_off");
218 if (off_power_str != nullptr) {
220 this->watts_off_ = std::stod(std::string(off_power_str));
221 } catch (const std::invalid_argument&) {
222 throw std::invalid_argument(std::string("Invalid value for property wattage_off of host ") + host_->get_cname() +
223 ": " + off_power_str);
226 /* watts_off is 0 by default */
229 HostEnergy::~HostEnergy() = default;
231 double HostEnergy::get_watt_idle_at(int pstate) const
233 if (not has_pstate_power_values_)
235 return power_range_watts_list_[pstate].idle_;
238 double HostEnergy::get_watt_min_at(int pstate) const
240 if (not has_pstate_power_values_)
242 return power_range_watts_list_[pstate].epsilon_;
245 double HostEnergy::get_watt_max_at(int pstate) const
247 if (not has_pstate_power_values_)
249 return power_range_watts_list_[pstate].max_;
252 double HostEnergy::get_power_range_slope_at(int pstate) const
254 if (not has_pstate_power_values_)
256 return power_range_watts_list_[pstate].slope_;
259 /** @brief Computes the power consumed by the host according to the current situation
261 * - If the host is off, that's the watts_off value
262 * - if it's on, take the current pstate and the current processor load into account */
263 double HostEnergy::get_current_watts_value()
265 if (this->pstate_ == pstate_off_) // The host is off (or was off at the beginning of this time interval)
266 return this->watts_off_;
268 double current_speed = host_->get_pstate_speed(this->pstate_);
272 if (current_speed <= 0)
273 // Some users declare a pstate of speed 0 flops (e.g., to model boot time).
274 // We consider that the machine is then fully loaded. That's arbitrary but it avoids a NaN
277 cpu_load = host_->get_load() / current_speed;
279 /* Divide by the number of cores here to have a value between 0 and 1 */
280 cpu_load /= host_->get_core_count();
282 if (cpu_load > 1) // This condition is true for energy_ptask on 32 bits, even if cpu_load is displayed as 1.000000
283 cpu_load = 1; // That may be an harmless rounding error?
285 host_was_used_ = true;
288 return get_current_watts_value(cpu_load);
291 /** @brief Computes the power that the host would consume at the provided processor load
293 * Whether the host is ON or OFF is not taken into account.
295 double HostEnergy::get_current_watts_value(double cpu_load) const
297 if (not has_pstate_power_values_)
300 /* Return watts_off if pstate == pstate_off (ie, if the host is off) */
301 if (this->pstate_ == pstate_off_) {
305 PowerRange power_range = power_range_watts_list_.at(this->pstate_);
306 double current_power;
311 * Something is going on, the host is not idle.
313 * The power consumption follows the regular model:
314 * P(cpu_load) = Pstatic + Pdynamic * cpu_load
315 * where Pstatic = power_range.epsilon_ and Pdynamic = power_range.slope_
316 * and the cpu_load is a value between 0 and 1.
318 current_power = power_range.epsilon_ + cpu_load * power_range.slope_;
322 /* The host is idle, take the dedicated value! */
323 current_power = power_range.idle_;
326 XBT_DEBUG("[get_current_watts] pstate=%i, epsilon_power=%f, max_power=%f, slope=%f", this->pstate_, power_range.epsilon_,
327 power_range.max_, power_range.slope_);
328 XBT_DEBUG("[get_current_watts] Current power (watts) = %f, load = %f", current_power, cpu_load);
330 return current_power;
333 double HostEnergy::get_consumed_energy()
335 if (last_updated_ < simgrid::s4u::Engine::get_clock()) // We need to simcall this as it modifies the environment
336 simgrid::kernel::actor::simcall_answered(std::bind(&HostEnergy::update, this));
338 return total_energy_;
341 void HostEnergy::init_watts_range_list()
343 const char* all_power_values_str = host_->get_property("wattage_per_state");
344 if (all_power_values_str == nullptr) {
345 XBT_WARN("No energetic profiles (wattage_per_state) given for host %s, using 0 W by default. Direct request of power/energy consumption of this host will fail.", host_->get_cname());
349 std::vector<std::string> all_power_values;
350 boost::split(all_power_values, all_power_values_str, boost::is_any_of(","));
351 XBT_DEBUG("%s: power properties: %s", host_->get_cname(), all_power_values_str);
353 xbt_assert(all_power_values.size() == host_->get_pstate_count(),
354 "Invalid XML file. Found %zu energetic profiles for %lu pstates", all_power_values.size(),
355 host_->get_pstate_count());
358 for (auto const& current_power_values_str : all_power_values) {
359 /* retrieve the power values associated with the pstate i */
360 std::vector<std::string> current_power_values;
361 boost::split(current_power_values, current_power_values_str, boost::is_any_of(":"));
363 xbt_assert(current_power_values.size() == 2 || current_power_values.size() == 3,
364 "Power properties incorrectly defined for host %s."
365 "It should be 'Idle:AllCores' (or 'Idle:Epsilon:AllCores') power values.",
369 double epsilon_power;
372 auto msg_idle = xbt::string_printf("Invalid Idle value for pstate %d on host %s", i, host_->get_cname());
373 auto msg_epsilon = xbt::string_printf("Invalid Epsilon value for pstate %d on host %s", i, host_->get_cname());
374 auto msg_max = xbt::string_printf("Invalid AllCores value for pstate %d on host %s", i, host_->get_cname());
376 idle_power = xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle.c_str());
377 if (current_power_values.size() == 2) { // Case: Idle:AllCores
378 epsilon_power = xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle.c_str());
379 max_power = xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_max.c_str());
380 } else { // Case: Idle:Epsilon:AllCores
381 epsilon_power = xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_epsilon.c_str());
382 max_power = xbt_str_parse_double((current_power_values.at(2)).c_str(), msg_max.c_str());
385 XBT_DEBUG("Creating PowerRange for host %s. Idle:%f, Epsilon:%f, AllCores:%f.", host_->get_cname(), idle_power, epsilon_power, max_power);
387 PowerRange range(idle_power, epsilon_power, max_power);
388 power_range_watts_list_.push_back(range);
392 has_pstate_power_values_ = true;
394 } // namespace plugin
395 } // namespace simgrid
397 using simgrid::plugin::HostEnergy;
399 /* **************************** events callback *************************** */
400 static void on_creation(simgrid::s4u::Host& host)
402 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
405 // TODO Trace: set to zero the energy variable associated to host->get_name()
407 host.extension_set(new HostEnergy(&host));
410 static void on_action_state_change(simgrid::kernel::resource::CpuAction const& action,
411 simgrid::kernel::resource::Action::State /*previous*/)
413 for (simgrid::kernel::resource::CpuImpl* const& cpu : action.cpus()) {
414 simgrid::s4u::Host* host = cpu->get_iface();
415 if (host != nullptr) {
416 // If it's a VM, take the corresponding PM
417 const simgrid::s4u::VirtualMachine* vm = dynamic_cast<simgrid::s4u::VirtualMachine*>(host);
418 if (vm) // If it's a VM, take the corresponding PM
421 // Get the host_energy extension for the relevant host
422 auto* host_energy = host->extension<HostEnergy>();
424 if (host_energy->get_last_update_time() < simgrid::s4u::Engine::get_clock())
425 host_energy->update();
430 /* This callback is fired either when the host changes its state (on/off) ("onStateChange") or its speed
431 * (because the user changed the pstate, or because of external trace events) ("onSpeedChange") */
432 static void on_host_change(simgrid::s4u::Host const& host)
434 if (dynamic_cast<simgrid::s4u::VirtualMachine const*>(&host)) // Ignore virtual machines
437 auto* host_energy = host.extension<HostEnergy>();
439 host_energy->update();
442 static void on_host_destruction(simgrid::s4u::Host const& host)
444 if (dynamic_cast<simgrid::s4u::VirtualMachine const*>(&host)) // Ignore virtual machines
447 XBT_INFO("Energy consumption of host %s: %f Joules", host.get_cname(),
448 host.extension<HostEnergy>()->get_consumed_energy());
451 static void on_simulation_end()
453 double total_energy = 0.0; // Total energy consumption (whole platform)
454 double used_hosts_energy = 0.0; // Energy consumed by hosts that computed something
455 for (simgrid::s4u::Host const* host : simgrid::s4u::Engine::get_instance()->get_all_hosts()) {
456 if (host && dynamic_cast<const simgrid::s4u::VirtualMachine*>(host) == nullptr) { // Ignore virtual machines
457 double energy = host->extension<HostEnergy>()->get_consumed_energy();
458 total_energy += energy;
459 if (host->extension<HostEnergy>()->host_was_used_)
460 used_hosts_energy += energy;
463 XBT_INFO("Total energy consumption: %f Joules (used hosts: %f Joules; unused/idle hosts: %f)", total_energy,
464 used_hosts_energy, total_energy - used_hosts_energy);
467 /* **************************** Public interface *************************** */
469 /** @ingroup plugin_host_energy
470 * @brief Enable host energy plugin
471 * @details Enable energy plugin to get joules consumption of each cpu. Call this function before loading your platform.
473 void sg_host_energy_plugin_init()
475 if (HostEnergy::EXTENSION_ID.valid())
478 HostEnergy::EXTENSION_ID = simgrid::s4u::Host::extension_create<HostEnergy>();
480 simgrid::s4u::Host::on_creation_cb(&on_creation);
481 simgrid::s4u::Host::on_state_change_cb(&on_host_change);
482 simgrid::s4u::Host::on_speed_change_cb(&on_host_change);
483 simgrid::s4u::Host::on_destruction_cb(&on_host_destruction);
484 simgrid::s4u::Engine::on_simulation_end_cb(&on_simulation_end);
485 simgrid::kernel::resource::CpuAction::on_state_change.connect(&on_action_state_change);
486 // We may only have one actor on a node. If that actor executes something like
487 // compute -> recv -> compute
488 // the recv operation will not trigger a "CpuAction::on_state_change". This means
489 // that the next trigger would be the 2nd compute, hence ignoring the idle time
490 // during the recv call. By updating at the beginning of a compute, we can
491 // fix that. (If the cpu is not idle, this is not required.)
492 simgrid::s4u::Exec::on_start_cb([](simgrid::s4u::Exec const& activity) {
493 if (activity.get_host_number() == 1) { // We only run on one host
494 simgrid::s4u::Host* host = activity.get_host();
495 const simgrid::s4u::VirtualMachine* vm = dynamic_cast<simgrid::s4u::VirtualMachine*>(host);
498 xbt_assert(host != nullptr);
499 host->extension<HostEnergy>()->update();
504 /** @ingroup plugin_host_energy
505 * @brief updates the consumption of all hosts
507 * After this call, sg_host_get_consumed_energy() will not interrupt your process
508 * (until after the next clock update).
510 void sg_host_energy_update_all()
512 simgrid::kernel::actor::simcall_answered([]() {
513 std::vector<simgrid::s4u::Host*> list = simgrid::s4u::Engine::get_instance()->get_all_hosts();
514 for (auto const& host : list)
515 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(host) == nullptr) { // Ignore virtual machines
516 xbt_assert(host != nullptr);
517 host->extension<HostEnergy>()->update();
522 static void ensure_plugin_inited()
524 if (not HostEnergy::EXTENSION_ID.valid())
525 throw simgrid::xbt::InitializationError("The Energy plugin is not active. Please call sg_host_energy_plugin_init() "
526 "before calling any function related to that plugin.");
529 /** @ingroup plugin_host_energy
530 * @brief Returns the total energy consumed by the host so far (in Joules)
532 * Please note that since the consumption is lazily updated, it may require a simcall to update it.
533 * The result is that the actor requesting this value will be interrupted,
534 * the value will be updated in kernel mode before returning the control to the requesting actor.
536 double sg_host_get_consumed_energy(const_sg_host_t host)
538 ensure_plugin_inited();
539 auto host_energy = host->extension<HostEnergy>();
540 xbt_assert(host_energy->has_pstate_power_values(), "No power range properties specified for host %s",
542 return host_energy->get_consumed_energy();
545 /** @ingroup plugin_host_energy
546 * @brief Get the amount of watt dissipated when the host is idling
548 double sg_host_get_idle_consumption(const_sg_host_t host)
550 ensure_plugin_inited();
551 return host->extension<HostEnergy>()->get_watt_idle_at(0);
554 /** @ingroup plugin_host_energy
555 * @brief Get the amount of watt dissipated at the given pstate when the host is idling
557 double sg_host_get_idle_consumption_at(const_sg_host_t host, int pstate)
559 ensure_plugin_inited();
560 return host->extension<HostEnergy>()->get_watt_idle_at(pstate);
563 /** @ingroup plugin_host_energy
564 * @brief Get the amount of watt dissipated at the given pstate when the host is at 0 or epsilon% CPU usage.
566 double sg_host_get_wattmin_at(const_sg_host_t host, int pstate)
568 ensure_plugin_inited();
569 return host->extension<HostEnergy>()->get_watt_min_at(pstate);
571 /** @ingroup plugin_host_energy
572 * @brief Returns the amount of watt dissipated at the given pstate when the host burns CPU at 100%
574 double sg_host_get_wattmax_at(const_sg_host_t host, int pstate)
576 ensure_plugin_inited();
577 return host->extension<HostEnergy>()->get_watt_max_at(pstate);
579 /** @ingroup plugin_host_energy
580 * @brief Returns the power slope at the given pstate
582 double sg_host_get_power_range_slope_at(const_sg_host_t host, int pstate)
584 ensure_plugin_inited();
585 return host->extension<HostEnergy>()->get_power_range_slope_at(pstate);
587 /** @ingroup plugin_host_energy
588 * @brief Returns the current consumption of the host
590 double sg_host_get_current_consumption(const_sg_host_t host)
592 ensure_plugin_inited();
593 auto host_energy = host->extension<HostEnergy>();
594 xbt_assert(host_energy->has_pstate_power_values(), "No power range properties specified for host %s",
596 return host_energy->get_current_watts_value();