1 /* Copyright (c) 2010-2017. 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/plugins/energy.h"
7 #include "simgrid/simix.hpp"
8 #include "src/plugins/vm/VirtualMachineImpl.hpp"
9 #include "src/surf/cpu_interface.hpp"
11 #include "simgrid/s4u/Engine.hpp"
13 #include <boost/algorithm/string/classification.hpp>
14 #include <boost/algorithm/string/split.hpp>
19 /** @addtogroup SURF_plugin_energy
22 This is the energy plugin, enabling to account not only for computation time,
23 but also for the dissipated energy in the simulated platform.
24 To activate this plugin, first call MSG_energy_plugin_init() before your #MSG_init(),
25 and then use MSG_host_get_consumed_energy() to retrieve the consumption of a given host.
27 When the host is on, this energy consumption naturally depends on both the
28 current CPU load and the host energy profile. According to our measurements,
29 the consumption is somehow linear in the amount of cores at full speed,
30 with an abnormality when all the cores are idle.
32 As a result, our energy model takes 4 parameters:
34 - \b Idle: instantaneous consumption (in Watt) when your host is up and running, but without anything to do.
35 - \b OneCore: instantaneous consumption (in Watt) when only one core is active, at 100%.
36 - \b AllCores: instantaneous consumption (in Watt) when all cores of the host are at 100%.
37 - \b Off: instantaneous consumption (in Watt) when the host is turned off.
39 Here is an example of XML declaration:
42 <host id="HostA" power="100.0Mf" cores="4">
43 <prop id="watt_per_state" value="100.0:120.0:200.0" />
44 <prop id="watt_off" value="10" />
48 This example gives the following parameters: \b Off is 10 Watts; \b Idle is 100 Watts; \b OneCore is 120 Watts and \b
49 AllCores is 200 Watts.
50 This is enough to compute the consumption as a function of the amount of loaded cores:
53 <tr><th>#Cores loaded</th><th>Consumption</th><th>Explanation</th></tr>
54 <tr><td>0</td><td> 100 Watts</td><td>Idle value</td></tr>
55 <tr><td>1</td><td> 120 Watts</td><td>OneCore value</td></tr>
56 <tr><td>2</td><td> 147 Watts</td><td>linear extrapolation between OneCore and AllCores</td></tr>
57 <tr><td>3</td><td> 173 Watts</td><td>linear extrapolation between OneCore and AllCores</td></tr>
58 <tr><td>4</td><td> 200 Watts</td><td>AllCores value</td></tr>
61 ### What if a given core is only at load 50%?
63 Well, that's impossible in SimGrid because we recompute everything each time
64 that the CPU starts or stops doing something. So if a core is at load 50% over
65 a period, it means that it is at load 100% half of the time and at load 0% the
66 rest of the time, and the model holds.
68 ### What if the host has only one core?
70 In this case, the parameters \b OneCore and \b AllCores are obviously the same.
71 Actually, SimGrid expect an energetic profile formated as 'Idle:Running' for mono-cores hosts.
72 If you insist on passing 3 parameters in this case, then you must have the same value for \b OneCore and \b AllCores.
75 <host id="HostC" power="100.0Mf" cores="1">
76 <prop id="watt_per_state" value="95.0:200.0" /> <!-- we may have used '95:200:200' instead -->
77 <prop id="watt_off" value="10" />
81 ### How does DVFS interact with the energy model?
83 If your host has several DVFS levels (several pstates), then you should
84 give the energetic profile of each pstate level:
87 <host id="HostC" power="100.0Mf,50.0Mf,20.0Mf" cores="4">
88 <prop id="watt_per_state" value="95.0:120.0:200.0, 93.0:115.0:170.0, 90.0:110.0:150.0" />
89 <prop id="watt_off" value="10" />
93 This encodes the following values
95 <tr><th>pstate</th><th>Performance</th><th>Idle</th><th>OneCore</th><th>AllCores</th></tr>
96 <tr><td>0</td><td>100 Mflop/s</td><td>95 Watts</td><td>120 Watts</td><td>200 Watts</td></tr>
97 <tr><td>1</td><td>50 Mflop/s</td><td>93 Watts</td><td>115 Watts</td><td>170 Watts</td></tr>
98 <tr><td>2</td><td>20 Mflop/s</td><td>90 Watts</td><td>110 Watts</td><td>150 Watts</td></tr>
101 To change the pstate of a given CPU, use the following functions:
102 #MSG_host_get_nb_pstates(), simgrid#s4u#Host#setPstate(), #MSG_host_get_power_peak_at().
106 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_energy, surf, "Logging specific to the SURF energy plugin");
117 PowerRange(double idle, double min, double max) : idle(idle), min(min), max(max) {}
122 static simgrid::xbt::Extension<simgrid::s4u::Host, HostEnergy> EXTENSION_ID;
124 explicit HostEnergy(simgrid::s4u::Host* ptr);
127 double getCurrentWattsValue(double cpu_load);
128 double getConsumedEnergy();
129 double getWattMinAt(int pstate);
130 double getWattMaxAt(int pstate);
134 void initWattsRangeList();
135 simgrid::s4u::Host* host = nullptr;
136 std::vector<PowerRange>
137 power_range_watts_list; /*< List of (min_power,max_power) pairs corresponding to each cpu pstate */
139 /* We need to keep track of what pstate has been used, as we will sometimes
140 * be notified only *after* a pstate has been used (but we need to update the energy consumption
141 * with the old pstate!)
146 double watts_off = 0.0; /*< Consumption when the machine is turned off (shutdown) */
147 double total_energy = 0.0; /*< Total energy consumed by the host */
148 double last_updated; /*< Timestamp of the last energy update event*/
151 simgrid::xbt::Extension<simgrid::s4u::Host, HostEnergy> HostEnergy::EXTENSION_ID;
153 /* Computes the consumption so far. Called lazily on need. */
154 void HostEnergy::update()
156 double start_time = this->last_updated;
157 double finish_time = surf_get_clock();
159 double current_speed = host->speed();
161 if (start_time < finish_time) {
162 // We may have start == finish if the past consumption was updated since the simcall was started
163 // for example if 2 actors requested to update the same host's consumption in a given scheduling round.
165 // Even in this case, we need to save the pstate for the next call (after this big if),
166 // which may have changed since that recent update.
168 if (current_speed <= 0)
169 // Some users declare a pstate of speed 0 flops (e.g., to model boot time).
170 // We consider that the machine is then fully loaded. That's arbitrary but it avoids a NaN
173 cpu_load = lmm_constraint_get_usage(host->pimpl_cpu->constraint()) / current_speed;
175 /** Divide by the number of cores here **/
176 cpu_load /= host->pimpl_cpu->coreCount();
178 if (cpu_load > 1) // A machine with a load > 1 consumes as much as a fully loaded machine, not more
181 /* The problem with this model is that the load is always 0 or 1, never something less.
182 * Another possibility could be to model the total energy as
184 * X/(X+Y)*W_idle + Y/(X+Y)*W_burn
186 * where X is the amount of idling cores, and Y the amount of computing cores.
189 double previous_energy = this->total_energy;
191 double instantaneous_consumption;
192 if (this->pstate == -1) // The host was off at the beginning of this time interval
193 instantaneous_consumption = this->watts_off;
195 instantaneous_consumption = this->getCurrentWattsValue(cpu_load);
197 double energy_this_step = instantaneous_consumption * (finish_time - start_time);
199 // TODO Trace: Trace energy_this_step from start_time to finish_time in host->name()
201 this->total_energy = previous_energy + energy_this_step;
202 this->last_updated = finish_time;
204 XBT_DEBUG("[update_energy of %s] period=[%.2f-%.2f]; current power peak=%.0E flop/s; consumption change: %.2f J -> "
206 host->cname(), start_time, finish_time, host->pimpl_cpu->speed_.peak, previous_energy, energy_this_step);
209 /* Save data for the upcoming time interval: whether it's on/off and the pstate if it's on */
210 this->pstate = host->isOn() ? host->pstate() : -1;
213 HostEnergy::HostEnergy(simgrid::s4u::Host* ptr) : host(ptr), last_updated(surf_get_clock())
215 initWattsRangeList();
217 const char* off_power_str = host->property("watt_off");
218 if (off_power_str != nullptr) {
219 char* msg = bprintf("Invalid value for property watt_off of host %s: %%s", host->cname());
220 this->watts_off = xbt_str_parse_double(off_power_str, msg);
223 /* watts_off is 0 by default */
226 HostEnergy::~HostEnergy() = default;
228 double HostEnergy::getWattMinAt(int pstate)
230 xbt_assert(not power_range_watts_list.empty(), "No power range properties specified for host %s", host->cname());
231 return power_range_watts_list[pstate].min;
234 double HostEnergy::getWattMaxAt(int pstate)
236 xbt_assert(not power_range_watts_list.empty(), "No power range properties specified for host %s", host->cname());
237 return power_range_watts_list[pstate].max;
240 /** @brief Computes the power consumed by the host according to the current pstate and processor load */
241 double HostEnergy::getCurrentWattsValue(double cpu_load)
243 xbt_assert(not power_range_watts_list.empty(), "No power range properties specified for host %s", host->cname());
245 /* min_power corresponds to the power consumed when only one core is active */
246 /* max_power is the power consumed at 100% cpu load */
247 auto range = power_range_watts_list.at(this->pstate);
248 double current_power = 0;
249 double min_power = 0;
250 double max_power = 0;
251 double power_slope = 0;
253 if (cpu_load > 0) { /* Something is going on, the machine is not idle */
254 double min_power = range.min;
255 double max_power = range.max;
258 * The min_power states how much we consume when only one single
259 * core is working. This means that when cpu_load == 1/coreCount, then
260 * current_power == min_power.
262 * The maximum must be reached when all cores are working (but 1 core was
263 * already accounted for by min_power)
264 * i.e., we need min_power + (maxCpuLoad-1/coreCount)*power_slope == max_power
265 * (maxCpuLoad is by definition 1)
268 int coreCount = host->coreCount();
269 double coreReciprocal = static_cast<double>(1) / static_cast<double>(coreCount);
271 power_slope = (max_power - min_power) / (1 - coreReciprocal);
273 power_slope = 0; // Should be 0, since max_power == min_power (in this case)
275 current_power = min_power + (cpu_load - coreReciprocal) * power_slope;
276 } else { /* Our machine is idle, take the dedicated value! */
277 current_power = range.idle;
280 XBT_DEBUG("[get_current_watts] min_power=%f, max_power=%f, slope=%f", min_power, max_power, power_slope);
281 XBT_DEBUG("[get_current_watts] Current power (watts) = %f, load = %f", current_power, cpu_load);
283 return current_power;
286 double HostEnergy::getConsumedEnergy()
288 if (last_updated < surf_get_clock()) // We need to simcall this as it modifies the environment
289 simgrid::simix::kernelImmediate(std::bind(&HostEnergy::update, this));
294 void HostEnergy::initWattsRangeList()
296 const char* all_power_values_str = host->property("watt_per_state");
297 if (all_power_values_str == nullptr)
300 std::vector<std::string> all_power_values;
301 boost::split(all_power_values, all_power_values_str, boost::is_any_of(","));
302 XBT_DEBUG("%s: profile: %s, cores: %d", host->cname(), all_power_values_str, host->coreCount());
305 for (auto current_power_values_str : all_power_values) {
306 /* retrieve the power values associated with the current pstate */
307 std::vector<std::string> current_power_values;
308 boost::split(current_power_values, current_power_values_str, boost::is_any_of(":"));
309 if (host->coreCount() == 1) {
310 xbt_assert(current_power_values.size() == 2 || current_power_values.size() == 3,
311 "Power properties incorrectly defined for host %s."
312 "It should be 'Idle:FullSpeed' power values because you have one core only.",
314 if (current_power_values.size() == 2) {
315 // In this case, 1core == AllCores
316 current_power_values.push_back(current_power_values.at(1));
317 } else { // size == 3
318 xbt_assert((current_power_values.at(1)) == (current_power_values.at(2)),
319 "Power properties incorrectly defined for host %s.\n"
320 "The energy profile of mono-cores should be formated as 'Idle:FullSpeed' only.\n"
321 "If you go for a 'Idle:OneCore:AllCores' power profile on mono-cores, then OneCore and AllCores "
326 xbt_assert(current_power_values.size() == 3,
327 "Power properties incorrectly defined for host %s."
328 "It should be 'Idle:OneCore:AllCores' power values because you have more than one core.",
332 /* min_power corresponds to the idle power (cpu load = 0) */
333 /* max_power is the power consumed at 100% cpu load */
334 char* msg_idle = bprintf("Invalid idle value for pstate %d on host %s: %%s", i, host->cname());
335 char* msg_min = bprintf("Invalid OneCore value for pstate %d on host %s: %%s", i, host->cname());
336 char* msg_max = bprintf("Invalid AllCores value for pstate %d on host %s: %%s", i, host->cname());
337 PowerRange range(xbt_str_parse_double((current_power_values.at(0)).c_str(), msg_idle),
338 xbt_str_parse_double((current_power_values.at(1)).c_str(), msg_min),
339 xbt_str_parse_double((current_power_values.at(2)).c_str(), msg_max));
340 power_range_watts_list.push_back(range);
350 using simgrid::energy::HostEnergy;
352 /* **************************** events callback *************************** */
353 static void onCreation(simgrid::s4u::Host& host)
355 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
358 //TODO Trace: set to zero the energy variable associated to host->name()
360 host.extension_set(new HostEnergy(&host));
363 static void onActionStateChange(simgrid::surf::CpuAction* action, simgrid::surf::Action::State previous)
365 for (simgrid::surf::Cpu* cpu : action->cpus()) {
366 simgrid::s4u::Host* host = cpu->getHost();
367 if (host != nullptr) {
369 // If it's a VM, take the corresponding PM
370 simgrid::s4u::VirtualMachine* vm = dynamic_cast<simgrid::s4u::VirtualMachine*>(host);
371 if (vm) // If it's a VM, take the corresponding PM
372 host = vm->pimpl_vm_->getPm();
374 // Get the host_energy extension for the relevant host
375 HostEnergy* host_energy = host->extension<HostEnergy>();
377 if (host_energy->last_updated < surf_get_clock())
378 host_energy->update();
383 /* This callback is fired either when the host changes its state (on/off) ("onStateChange") or its speed
384 * (because the user changed the pstate, or because of external trace events) ("onSpeedChange") */
385 static void onHostChange(simgrid::s4u::Host& host)
387 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
390 HostEnergy* host_energy = host.extension<HostEnergy>();
392 host_energy->update();
395 static void onHostDestruction(simgrid::s4u::Host& host)
397 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
400 HostEnergy* host_energy = host.extension<HostEnergy>();
401 host_energy->update();
402 XBT_INFO("Energy consumption of host %s: %f Joules", host.cname(), host_energy->getConsumedEnergy());
405 static void onSimulationEnd()
407 sg_host_t* host_list = sg_host_list();
408 int host_count = sg_host_count();
409 double total_energy = 0.0; // Total energy consumption (whole platform)
410 double used_hosts_energy = 0.0; // Energy consumed by hosts that computed something
411 for (int i = 0; i < host_count; i++) {
412 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(host_list[i]) == nullptr) { // Ignore virtual machines
414 bool host_was_used = (host_list[i]->extension<HostEnergy>()->last_updated != 0);
415 double energy = host_list[i]->extension<HostEnergy>()->getConsumedEnergy();
416 total_energy += energy;
418 used_hosts_energy += energy;
421 XBT_INFO("Total energy consumption: %f Joules (used hosts: %f Joules; unused/idle hosts: %f)",
422 total_energy, used_hosts_energy, total_energy - used_hosts_energy);
426 /* **************************** Public interface *************************** */
429 /** \ingroup SURF_plugin_energy
430 * \brief Enable host energy plugin
431 * \details Enable energy plugin to get joules consumption of each cpu. Call this function before #MSG_init().
433 void sg_host_energy_plugin_init()
435 if (HostEnergy::EXTENSION_ID.valid())
438 HostEnergy::EXTENSION_ID = simgrid::s4u::Host::extension_create<HostEnergy>();
440 simgrid::s4u::Host::onCreation.connect(&onCreation);
441 simgrid::s4u::Host::onStateChange.connect(&onHostChange);
442 simgrid::s4u::Host::onSpeedChange.connect(&onHostChange);
443 simgrid::s4u::Host::onDestruction.connect(&onHostDestruction);
444 simgrid::s4u::onSimulationEnd.connect(&onSimulationEnd);
445 simgrid::surf::CpuAction::onStateChange.connect(&onActionStateChange);
448 /** @brief updates the consumption of all hosts
450 * After this call, sg_host_get_consumed_energy() will not interrupt your process
451 * (until after the next clock update).
453 void sg_host_energy_update_all()
455 simgrid::simix::kernelImmediate([]() {
456 std::vector<simgrid::s4u::Host*> list;
457 simgrid::s4u::Engine::instance()->hostList(&list);
458 for (auto host : list)
459 host->extension<HostEnergy>()->update();
463 /** @brief Returns the total energy consumed by the host so far (in Joules)
465 * Please note that since the consumption is lazily updated, it may require a simcall to update it.
466 * The result is that the actor requesting this value will be interrupted,
467 * the value will be updated in kernel mode before returning the control to the requesting actor.
469 * See also @ref SURF_plugin_energy.
471 double sg_host_get_consumed_energy(sg_host_t host)
473 xbt_assert(HostEnergy::EXTENSION_ID.valid(),
474 "The Energy plugin is not active. Please call sg_energy_plugin_init() during initialization.");
475 return host->extension<HostEnergy>()->getConsumedEnergy();
478 /** @brief Get the amount of watt dissipated at the given pstate when the host is idling */
479 double sg_host_get_wattmin_at(sg_host_t host, int pstate)
481 xbt_assert(HostEnergy::EXTENSION_ID.valid(),
482 "The Energy plugin is not active. Please call sg_energy_plugin_init() during initialization.");
483 return host->extension<HostEnergy>()->getWattMinAt(pstate);
485 /** @brief Returns the amount of watt dissipated at the given pstate when the host burns CPU at 100% */
486 double sg_host_get_wattmax_at(sg_host_t host, int pstate)
488 xbt_assert(HostEnergy::EXTENSION_ID.valid(),
489 "The Energy plugin is not active. Please call sg_energy_plugin_init() during initialization.");
490 return host->extension<HostEnergy>()->getWattMaxAt(pstate);
493 /** @brief Returns the current consumption of the host */
494 double sg_host_get_current_consumption(sg_host_t host)
496 xbt_assert(HostEnergy::EXTENSION_ID.valid(),
497 "The Energy plugin is not active. Please call sg_energy_plugin_init() during initialization.");
498 double cpu_load = lmm_constraint_get_usage(host->pimpl_cpu->constraint()) / host->speed();
499 return host->extension<HostEnergy>()->getCurrentWattsValue(cpu_load);