+++ /dev/null
-/* Copyright (c) 2010-2018. The SimGrid Team. All rights reserved. */
-
-/* This program is free software; you can redistribute it and/or modify it
- * under the terms of the license (GNU LGPL) which comes with this package. */
-
-#include "simgrid/plugins/dvfs.h"
-#include "simgrid/plugins/load.h"
-#include "src/plugins/vm/VirtualMachineImpl.hpp"
-#include <xbt/config.hpp>
-
-#include <boost/algorithm/string.hpp>
-
-/** @addtogroup SURF_plugin_load
-
- This plugin makes it very simple for users to obtain the current load for each host.
-
-*/
-
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_plugin_dvfs, surf, "Logging specific to the SURF HostDvfs plugin");
-
-static const char* property_sampling_rate = "plugin/dvfs/sampling_rate";
-static const char* property_governor = "plugin/dvfs/governor";
-
-namespace simgrid {
-namespace plugin {
-
-namespace dvfs {
-class Governor {
-
-private:
- simgrid::s4u::Host* const host_;
-
-protected:
- simgrid::s4u::Host* get_host() const { return host_; }
-
-public:
- double sampling_rate;
-
- explicit Governor(simgrid::s4u::Host* ptr) : host_(ptr) { init(); }
- virtual ~Governor() = default;
-
- void init()
- {
- const char* local_sampling_rate_config = host_->get_property(property_sampling_rate);
- double global_sampling_rate_config = simgrid::config::get_value<double>(property_sampling_rate);
- if (local_sampling_rate_config != nullptr) {
- sampling_rate = std::stod(local_sampling_rate_config);
- } else {
- sampling_rate = global_sampling_rate_config;
- }
- }
-
- virtual void update() = 0;
- virtual std::string getName() = 0;
- double samplingRate() { return sampling_rate; }
-};
-
-/**
- * The linux kernel doc describes this governor as follows:
- * https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt
- *
- * > The CPUfreq governor "performance" sets the CPU statically to the
- * > highest frequency within the borders of scaling_min_freq and
- * > scaling_max_freq.
- *
- * We do not support scaling_min_freq/scaling_max_freq -- we just pick the lowest frequency.
- */
-class Performance : public Governor {
-public:
- explicit Performance(simgrid::s4u::Host* ptr) : Governor(ptr) {}
-
- void update() override { get_host()->set_pstate(0); }
- std::string getName() override { return "Performance"; }
-};
-
-/**
- * The linux kernel doc describes this governor as follows:
- * https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt
- *
- * > The CPUfreq governor "powersave" sets the CPU statically to the
- * > lowest frequency within the borders of scaling_min_freq and
- * > scaling_max_freq.
- *
- * We do not support scaling_min_freq/scaling_max_freq -- we just pick the lowest frequency.
- */
-class Powersave : public Governor {
-public:
- explicit Powersave(simgrid::s4u::Host* ptr) : Governor(ptr) {}
-
- void update() override { get_host()->set_pstate(get_host()->get_pstate_count() - 1); }
- std::string getName() override { return "Powersave"; }
-};
-
-/**
- * The linux kernel doc describes this governor as follows:
- * https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt
- *
- * > The CPUfreq governor "ondemand" sets the CPU frequency depending on the
- * > current system load. [...] when triggered, cpufreq checks
- * > the CPU-usage statistics over the last period and the governor sets the
- * > CPU accordingly.
- */
-class OnDemand : public Governor {
- /**
- * See https://elixir.bootlin.com/linux/v4.15.4/source/drivers/cpufreq/cpufreq_ondemand.c
- * DEF_FREQUENCY_UP_THRESHOLD and od_update()
- */
- double freq_up_threshold = 0.80;
-
-public:
- explicit OnDemand(simgrid::s4u::Host* ptr) : Governor(ptr) {}
-
- std::string getName() override { return "OnDemand"; }
- void update() override
- {
- double load = get_host()->get_core_count() * sg_host_get_avg_load(get_host());
- sg_host_load_reset(get_host()); // Only consider the period between two calls to this method!
-
- if (load > freq_up_threshold) {
- get_host()->set_pstate(0); /* Run at max. performance! */
- XBT_INFO("Load: %f > threshold: %f --> changed to pstate %i", load, freq_up_threshold, 0);
- } else {
- /* The actual implementation uses a formula here: (See Kernel file cpufreq_ondemand.c:158)
- *
- * freq_next = min_f + load * (max_f - min_f) / 100
- *
- * So they assume that frequency increases by 100 MHz. We will just use
- * lowest_pstate - load*pstatesCount()
- */
- int max_pstate = get_host()->get_pstate_count() - 1;
- // Load is now < freq_up_threshold; exclude pstate 0 (the fastest)
- // because pstate 0 can only be selected if load > freq_up_threshold
- int new_pstate = max_pstate - load * (max_pstate + 1);
- get_host()->set_pstate(new_pstate);
-
- XBT_DEBUG("Load: %f < threshold: %f --> changed to pstate %i", load, freq_up_threshold, new_pstate);
- }
- }
-};
-
-/**
- * This is the conservative governor, which is very similar to the
- * OnDemand governor. The Linux Kernel Documentation describes it
- * very well, see https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt:
- *
- * > The CPUfreq governor "conservative", much like the "ondemand"
- * > governor, sets the CPU frequency depending on the current usage. It
- * > differs in behaviour in that it gracefully increases and decreases the
- * > CPU speed rather than jumping to max speed the moment there is any load
- * > on the CPU. This behaviour is more suitable in a battery powered
- * > environment.
- */
-class Conservative : public Governor {
- double freq_up_threshold = .8;
- double freq_down_threshold = .2;
-
-public:
- explicit Conservative(simgrid::s4u::Host* ptr) : Governor(ptr) {}
-
- virtual std::string getName() override { return "Conservative"; }
- virtual void update() override
- {
- double load = get_host()->get_core_count() * sg_host_get_avg_load(get_host());
- int pstate = get_host()->get_pstate();
- sg_host_load_reset(get_host()); // Only consider the period between two calls to this method!
-
- if (load > freq_up_threshold) {
- if (pstate != 0) {
- get_host()->set_pstate(pstate - 1);
- XBT_INFO("Load: %f > threshold: %f -> increasing performance to pstate %d", load, freq_up_threshold, pstate - 1);
- }
- else {
- XBT_DEBUG("Load: %f > threshold: %f -> but cannot speed up even more, already in highest pstate %d", load, freq_up_threshold, pstate);
- }
- } else if (load < freq_down_threshold) {
- int max_pstate = get_host()->get_pstate_count() - 1;
- if (pstate != max_pstate) { // Are we in the slowest pstate already?
- get_host()->set_pstate(pstate + 1);
- XBT_INFO("Load: %f < threshold: %f -> slowing down to pstate %d", load, freq_down_threshold, pstate + 1);
- }
- else {
- XBT_DEBUG("Load: %f < threshold: %f -> cannot slow down even more, already in slowest pstate %d", load, freq_down_threshold, pstate);
- }
- }
- }
-};
-
-/**
- * Add this to your host tag:
- * - \<prop id="plugin/dvfs/governor" value="performance" /\>
- *
- * Valid values as of now are: performance, powersave, ondemand, conservative
- * It doesn't matter if you use uppercase or lowercase.
- *
- * For the sampling rate, use this:
- *
- * - \<prop id="plugin/dvfs/sampling_rate" value="2" /\>
- *
- * This will run the update() method of the specified governor every 2 seconds
- * on that host.
- *
- * These properties can also be used within the \<config\> tag to configure
- * these values globally. Using them within the \<host\> will overwrite this
- * global configuration
- */
-class HostDvfs {
-public:
- static simgrid::xbt::Extension<simgrid::s4u::Host, HostDvfs> EXTENSION_ID;
-
- explicit HostDvfs(simgrid::s4u::Host*);
- ~HostDvfs();
-};
-
-simgrid::xbt::Extension<simgrid::s4u::Host, HostDvfs> HostDvfs::EXTENSION_ID;
-
-HostDvfs::HostDvfs(simgrid::s4u::Host* ptr) {}
-
-HostDvfs::~HostDvfs() = default;
-}
-}
-}
-
-using simgrid::plugin::dvfs::HostDvfs;
-
-/* **************************** events callback *************************** */
-static void on_host_added(simgrid::s4u::Host& host)
-{
- if (dynamic_cast<simgrid::s4u::VirtualMachine*>(&host)) // Ignore virtual machines
- return;
-
- std::string name = std::string("dvfs-daemon-") + host.get_cname();
- simgrid::s4u::ActorPtr daemon = simgrid::s4u::Actor::create(name.c_str(), &host, []() {
- /**
- * This lambda function is the function the actor (daemon) will execute
- * all the time - in the case of the dvfs plugin, this controls when to
- * lower/raise the frequency.
- */
- simgrid::s4u::ActorPtr daemon_proc = simgrid::s4u::Actor::self();
-
- XBT_DEBUG("DVFS process on %s is a daemon: %d", daemon_proc->get_host()->get_cname(), daemon_proc->is_daemon());
-
- std::string dvfs_governor;
- const char* host_conf = daemon_proc->get_host()->get_property(property_governor);
- if (host_conf != nullptr) {
- dvfs_governor = std::string(daemon_proc->get_host()->get_property(property_governor));
- boost::algorithm::to_lower(dvfs_governor);
- } else {
- dvfs_governor = simgrid::config::get_value<std::string>(property_governor);
- boost::algorithm::to_lower(dvfs_governor);
- }
-
- auto governor = [&dvfs_governor, &daemon_proc]() {
- if (dvfs_governor == "conservative") {
- return std::unique_ptr<simgrid::plugin::dvfs::Governor>(
- new simgrid::plugin::dvfs::Conservative(daemon_proc->get_host()));
- } else if (dvfs_governor == "ondemand") {
- return std::unique_ptr<simgrid::plugin::dvfs::Governor>(
- new simgrid::plugin::dvfs::OnDemand(daemon_proc->get_host()));
- } else if (dvfs_governor == "performance") {
- return std::unique_ptr<simgrid::plugin::dvfs::Governor>(
- new simgrid::plugin::dvfs::Performance(daemon_proc->get_host()));
- } else if (dvfs_governor == "powersave") {
- return std::unique_ptr<simgrid::plugin::dvfs::Governor>(
- new simgrid::plugin::dvfs::Powersave(daemon_proc->get_host()));
- } else {
- XBT_CRITICAL("No governor specified for host %s, falling back to Performance",
- daemon_proc->get_host()->get_cname());
- return std::unique_ptr<simgrid::plugin::dvfs::Governor>(
- new simgrid::plugin::dvfs::Performance(daemon_proc->get_host()));
- }
- }();
-
- while (1) {
- // Sleep *before* updating; important for startup (i.e., t = 0).
- // In the beginning, we want to go with the pstates specified in the platform file
- // (so we sleep first)
- simgrid::s4u::this_actor::sleep_for(governor->samplingRate());
- governor->update();
- XBT_DEBUG("Governor (%s) just updated!", governor->getName().c_str());
- }
-
- XBT_WARN("I should have never reached this point: daemons should be killed when all regular processes are done");
- return 0;
- });
-
- // This call must be placed in this function. Otherweise, the daemonize() call comes too late and
- // SMPI will take this process as an MPI process!
- daemon->daemonize();
-}
-
-/* **************************** Public interface *************************** */
-
-/** \ingroup SURF_plugin_load
- * \brief Initializes the HostDvfs plugin
- * \details The HostDvfs plugin provides an API to get the current load of each host.
- */
-void sg_host_dvfs_plugin_init()
-{
- if (HostDvfs::EXTENSION_ID.valid())
- return;
-
- HostDvfs::EXTENSION_ID = simgrid::s4u::Host::extension_create<HostDvfs>();
-
- sg_host_load_plugin_init();
-
- simgrid::s4u::Host::on_creation.connect(&on_host_added);
- simgrid::config::declare_flag<double>(
- property_sampling_rate, "How often should the dvfs plugin check whether the frequency needs to be changed?", 0.1);
- simgrid::config::declare_flag<std::string>(
- property_governor, "Which Governor should be used that adapts the CPU frequency?", "performance");
-}
