1 /* Copyright (c) 2010, 2012-2018. 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/dvfs.h"
7 #include "simgrid/plugins/load.h"
8 #include "simgrid/simix.hpp"
9 #include "src/plugins/vm/VirtualMachineImpl.hpp"
10 #include "src/surf/cpu_interface.hpp"
12 #include <boost/algorithm/string.hpp>
13 #include <boost/algorithm/string/classification.hpp>
14 #include <boost/algorithm/string/split.hpp>
15 #include <simgrid/msg.h>
16 #include <simgrid/s4u/Engine.hpp>
20 #include <xbt/config.hpp>
22 /** @addtogroup SURF_plugin_load
24 This plugin makes it very simple for users to obtain the current load for each host.
28 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_plugin_dvfs, surf, "Logging specific to the SURF HostDvfs plugin");
37 simgrid::s4u::Host* host;
42 explicit Governor(simgrid::s4u::Host* ptr) : host(ptr) { init(); }
43 virtual ~Governor() = default;
47 const char* local_sampling_rate_config = host->getProperty("plugin/dvfs/sampling_rate");
48 double global_sampling_rate_config = xbt_cfg_get_double("plugin/dvfs/sampling_rate");
49 if (local_sampling_rate_config != nullptr) {
50 sampling_rate = std::stod(local_sampling_rate_config);
52 sampling_rate = global_sampling_rate_config;
56 virtual void update() {}
57 double samplingRate() { return sampling_rate; }
60 class Performance : public Governor {
62 explicit Performance(simgrid::s4u::Host* ptr) : Governor(ptr) {}
64 void update() { host->setPstate(0); }
67 class Powersave : public Governor {
69 explicit Powersave(simgrid::s4u::Host* ptr) : Governor(ptr) {}
71 void update() { host->setPstate(host->getPstatesCount() - 1); }
74 class OnDemand : public Governor {
75 double freq_up_threshold = 0.95;
78 explicit OnDemand(simgrid::s4u::Host* ptr) : Governor(ptr) {}
82 double load = sg_host_get_current_load(host);
84 // FIXME I don't like that we multiply with the getCoreCount() just here...
85 if (load*host->getCoreCount() > freq_up_threshold) {
86 host->setPstate(0); /* Run at max. performance! */
87 XBT_INFO("Changed to pstate %f", 0.0);
89 /* The actual implementation uses a formula here: (See Kernel file cpufreq_ondemand.c:158)
91 * freq_next = min_f + load * (max_f - min_f) / 100
93 * So they assume that frequency increases by 100 MHz. We will just use
94 * lowest_pstate - load*pstatesCount()
96 int max_pstate = host->getPstatesCount() - 1;
97 int new_pstate = max_pstate - load * max_pstate;
98 host->setPstate(new_pstate);
100 XBT_DEBUG("Load: %f --> changed to pstate %i", load*host->getCoreCount(), new_pstate);
105 class Conservative : public Governor {
106 double freq_up_threshold = .8;
107 double freq_down_threshold = .2;
110 explicit Conservative(simgrid::s4u::Host* ptr) : Governor(ptr) {}
114 double load = sg_host_get_current_load(host)*host->getCoreCount();
115 int pstate = host->getPstate();
117 if (load > freq_up_threshold) {
119 host->setPstate(pstate - 1);
120 XBT_INFO("Load: %f > threshold: %f -> increasing performance to pstate %d", load, freq_up_threshold, pstate - 1);
123 XBT_DEBUG("Load: %f > threshold: %f -> but cannot speed up even more, already in highest pstate %d", load, freq_up_threshold, pstate);
127 if (load < freq_down_threshold) {
128 int max_pstate = host->getPstatesCount() - 1;
129 if (pstate != max_pstate) { // Are we in the slowest pstate already?
130 host->setPstate(pstate + 1);
131 XBT_INFO("Load: %f < threshold: %f -> slowing down to pstate %d", load, freq_down_threshold, pstate + 1);
134 XBT_DEBUG("Load: %f < threshold: %f -> cannot slow down even more, already in slowest pstate %d", load, freq_down_threshold, pstate);
143 static simgrid::xbt::Extension<simgrid::s4u::Host, HostDvfs> EXTENSION_ID;
145 explicit HostDvfs(simgrid::s4u::Host*);
149 simgrid::xbt::Extension<simgrid::s4u::Host, HostDvfs> HostDvfs::EXTENSION_ID;
151 HostDvfs::HostDvfs(simgrid::s4u::Host* ptr) {}
153 HostDvfs::~HostDvfs() = default;
157 using simgrid::plugin::HostDvfs;
159 /* **************************** events callback *************************** */
160 static void on_host_added(simgrid::s4u::Host& host)
162 if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
165 std::string name = std::string("dvfs-daemon-") + host.getCname();
166 simgrid::s4u::ActorPtr daemon = simgrid::s4u::Actor::createActor(name.c_str(), &host, []() {
168 * This lambda function is the function the actor (daemon) will execute
169 * all the time - in the case of the dvfs plugin, this controls when to
170 * lower/raise the frequency.
172 simgrid::s4u::ActorPtr daemonProc = simgrid::s4u::Actor::self();
174 XBT_DEBUG("DVFS process on %s is a daemon: %d", daemonProc->getHost()->getName().c_str(), daemonProc->isDaemon());
176 std::string dvfs_governor;
177 const char* host_conf = daemonProc->getHost()->getProperty("plugin/dvfs/governor");
178 if (host_conf != nullptr) {
179 dvfs_governor = std::string(daemonProc->getHost()->getProperty("plugin/dvfs/governor"));
180 boost::algorithm::to_lower(dvfs_governor);
182 dvfs_governor = xbt_cfg_get_string("plugin/dvfs/governor");
183 boost::algorithm::to_lower(dvfs_governor);
186 simgrid::plugin::dvfs::Governor governor(daemonProc->getHost());
187 if (dvfs_governor == "conservative") {
188 governor = simgrid::plugin::dvfs::Conservative(daemonProc->getHost());
192 // Sleep *before* updating; important for startup (i.e., t = 0).
193 // In the beginning, we want to go with the pstates specified in the platform file
194 // (so we sleep first)
195 simgrid::s4u::this_actor::sleep_for(governor.samplingRate());
197 XBT_INFO("Governor just updated!");
200 XBT_WARN("I should have never reached this point: daemons should be killed when all regular processes are done");
204 // This call must be placed in this function. Otherweise, the daemonize() call comes too late and
205 // SMPI will take this process as an MPI process!
209 /* **************************** Public interface *************************** */
212 /** \ingroup SURF_plugin_load
213 * \brief Initializes the HostDvfs plugin
214 * \details The HostDvfs plugin provides an API to get the current load of each host.
216 void sg_host_dvfs_plugin_init()
218 if (HostDvfs::EXTENSION_ID.valid())
221 HostDvfs::EXTENSION_ID = simgrid::s4u::Host::extension_create<HostDvfs>();
223 sg_host_load_plugin_init();
225 simgrid::s4u::Host::onCreation.connect(&on_host_added);
226 xbt_cfg_register_double("plugin/dvfs/sampling_rate", 0.1, nullptr,
227 "How often should the dvfs plugin check whether the frequency needs to be changed?");
228 xbt_cfg_register_string("plugin/dvfs/governor", "performance", nullptr,
229 "Which Governor should be used that adapts the CPU frequency?");