+++ /dev/null
-/* Copyright (c) 2010-2023. 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 <simgrid/s4u/Actor.hpp>
-#include <simgrid/s4u/Host.hpp>
-#include <simgrid/s4u/VirtualMachine.hpp>
-#include <xbt/asserts.h>
-#include <xbt/config.hpp>
-
-#include "src/internal_config.h" // HAVE_SMPI
-#include "src/kernel/activity/CommImpl.hpp"
-#include "src/kernel/resource/NetworkModel.hpp"
-#include "src/simgrid/module.hpp"
-#if HAVE_SMPI
-#include "src/smpi/include/smpi_request.hpp"
-#include "src/smpi/plugins/ampi/ampi.hpp"
-#endif
-
-#include <boost/algorithm/string.hpp>
-#include <string_view>
-
-SIMGRID_REGISTER_PLUGIN(host_dvfs, "Dvfs support", &sg_host_dvfs_plugin_init)
-
-static simgrid::config::Flag<double>
- cfg_sampling_rate("plugin/dvfs/sampling-rate",
- "How often should the dvfs plugin check whether the frequency needs to be changed?", 0.1,
- [](double val) {
- if (val != 0.1)
- sg_host_dvfs_plugin_init();
- });
-
-static simgrid::config::Flag<std::string> cfg_governor("plugin/dvfs/governor",
- "Which Governor should be used that adapts the CPU frequency?",
- "performance",
-
- std::map<std::string, std::string, std::less<>>({
-#if HAVE_SMPI
- {"adagio", "TODO: Doc"},
-#endif
- {"conservative", "TODO: Doc"}, {"ondemand", "TODO: Doc"},
- {"performance", "TODO: Doc"}, {"powersave", "TODO: Doc"},
- }),
-
- [](std::string_view val) {
- if (val != "performance")
- sg_host_dvfs_plugin_init();
- });
-
-static simgrid::config::Flag<int>
- cfg_min_pstate("plugin/dvfs/min-pstate",
- "Which pstate is the minimum (and hence fastest) pstate for this governor?", 0);
-
-static constexpr int MAX_PSTATE_NOT_LIMITED = -1;
-static simgrid::config::Flag<int>
- cfg_max_pstate("plugin/dvfs/max-pstate",
- "Which pstate is the maximum (and hence slowest) pstate for this governor?", MAX_PSTATE_NOT_LIMITED);
-
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(host_dvfs, kernel, "Logging specific to the HostDvfs plugin");
-
-namespace simgrid::plugin::dvfs {
-
-/**
- * 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 Governor {
- simgrid::s4u::Host* const host_;
- double sampling_rate_;
- unsigned long min_pstate = cfg_min_pstate; //< Never use a pstate less than this one
- unsigned long max_pstate = cfg_max_pstate; //< Never use a pstate larger than this one
-
-public:
- explicit Governor(simgrid::s4u::Host* ptr)
- : host_(ptr)
- {
- if (cfg_max_pstate == MAX_PSTATE_NOT_LIMITED)
- max_pstate = host_->get_pstate_count() - 1;
- init();
- }
- virtual ~Governor() = default;
- virtual std::string get_name() const = 0;
- simgrid::s4u::Host* get_host() const { return host_; }
- unsigned long get_min_pstate() const { return min_pstate; }
- unsigned long get_max_pstate() const { return max_pstate; }
-
- void init()
- {
- if (const char* local_sampling_rate_config = host_->get_property(cfg_sampling_rate.get_name())) {
- sampling_rate_ = std::stod(local_sampling_rate_config);
- } else {
- sampling_rate_ = cfg_sampling_rate;
- }
- if (const char* local_min_pstate_config = host_->get_property(cfg_min_pstate.get_name())) {
- min_pstate = std::stoul(local_min_pstate_config);
- }
-
- if (const char* local_max_pstate_config = host_->get_property(cfg_max_pstate.get_name())) {
- max_pstate = std::stoul(local_max_pstate_config);
- }
- xbt_assert(max_pstate <= host_->get_pstate_count() - 1, "Value for max_pstate too large!");
- xbt_assert(min_pstate <= max_pstate, "min_pstate is larger than max_pstate!");
- }
-
- virtual void update() = 0;
- double get_sampling_rate() const { 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:
- using Governor::Governor;
- std::string get_name() const override { return "Performance"; }
-
- void update() override { get_host()->set_pstate(get_min_pstate()); }
-};
-
-/**
- * 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:
- using Governor::Governor;
- std::string get_name() const override { return "Powersave"; }
-
- void update() override { get_host()->set_pstate(get_max_pstate()); }
-};
-
-/**
- * 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:
- using Governor::Governor;
- std::string get_name() const 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(get_min_pstate()); /* Run at max. performance! */
- XBT_INFO("Load: %f > threshold: %f --> changed to pstate %lu", load, freq_up_threshold_, get_min_pstate());
- } 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()
- */
- // Load is now < freq_up_threshold; exclude pstate 0 (the fastest)
- // because pstate 0 can only be selected if load > freq_up_threshold_
- auto new_pstate = get_max_pstate() - static_cast<unsigned long>(load) * (get_max_pstate() + 1);
- if (new_pstate < get_min_pstate())
- new_pstate = get_min_pstate();
- get_host()->set_pstate(new_pstate);
-
- XBT_DEBUG("Load: %f < threshold: %f --> changed to pstate %lu", 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 behavior 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 behavior is more suitable in a battery powered
- * > environment.
- */
-class Conservative : public Governor {
- double freq_up_threshold_ = .8;
- double freq_down_threshold_ = .2;
-
-public:
- using Governor::Governor;
- std::string get_name() const override { return "Conservative"; }
-
- void update() override
- {
- double load = get_host()->get_core_count() * sg_host_get_avg_load(get_host());
- unsigned long 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 != get_min_pstate()) {
- get_host()->set_pstate(pstate - 1);
- XBT_INFO("Load: %f > threshold: %f -> increasing performance to pstate %lu", load, freq_up_threshold_,
- pstate - 1);
- } else {
- XBT_DEBUG("Load: %f > threshold: %f -> but cannot speed up even more, already in highest pstate %lu", load,
- freq_up_threshold_, pstate);
- }
- } else if (load < freq_down_threshold_) {
- if (pstate != get_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 %lu", load, freq_down_threshold_, pstate + 1);
- } else {
- XBT_DEBUG("Load: %f < threshold: %f -> cannot slow down even more, already in slowest pstate %lu", load,
- freq_down_threshold_, pstate);
- }
- }
- }
-};
-
-#if HAVE_SMPI
-class Adagio : public Governor {
- unsigned long best_pstate = 0;
- double start_time = 0;
- double comp_counter = 0;
- double comp_timer = 0;
-
- std::vector<std::vector<double>> rates; // Each host + all frequencies of that host
-
- unsigned int task_id = 0;
- bool iteration_running = false; /*< Are we currently between iteration_in and iteration_out calls? */
-
-public:
- explicit Adagio(simgrid::s4u::Host* ptr)
- : Governor(ptr), rates(100, std::vector<double>(ptr->get_pstate_count(), 0.0))
- {
- simgrid::smpi::plugin::ampi::on_iteration_in.connect([this](simgrid::s4u::Actor const& actor) {
- // Every instance of this class subscribes to this event, so one per host
- // This means that for any actor, all 'hosts' are normally notified of these
- // changes, even those who don't currently run the actor 'proc_id'.
- // -> Let's check if this signal call is for us!
- if (get_host() == actor.get_host()) {
- iteration_running = true;
- }
- });
- simgrid::smpi::plugin::ampi::on_iteration_out.connect([this](simgrid::s4u::Actor const& actor) {
- if (get_host() == actor.get_host()) {
- iteration_running = false;
- task_id = 0;
- }
- });
- simgrid::s4u::Exec::on_start_cb([this](simgrid::s4u::Exec const& activity) {
- if (activity.get_host() == get_host())
- pre_task();
- });
- simgrid::s4u::Exec::on_completion_cb([this](simgrid::s4u::Exec const& exec) {
- // For more than one host (not yet supported), we can access the host via
- // simcalls_.front()->issuer->get_iface()->get_host()
- if (exec.get_host() == get_host() && iteration_running) {
- comp_timer += exec.get_finish_time() - exec.get_start_time();
- }
- });
- // FIXME I think that this fires at the same time for all hosts, so when the src sends something,
- // the dst will be notified even though it didn't even arrive at the recv yet
- simgrid::s4u::Comm::on_start_cb([this](const s4u::Comm& comm) {
- if ((get_host() == comm.get_sender()->get_host() || get_host() == comm.get_receiver()->get_host()) &&
- iteration_running) {
- post_task();
- }
- });
- }
-
- std::string get_name() const override { return "Adagio"; }
-
- void pre_task()
- {
- sg_host_load_reset(get_host());
- comp_counter = sg_host_get_computed_flops(get_host()); // Should be 0 because of the reset
- comp_timer = 0;
- start_time = simgrid::s4u::Engine::get_clock();
- if (rates.size() <= task_id)
- rates.resize(task_id + 5, std::vector<double>(get_host()->get_pstate_count(), 0.0));
- if (rates[task_id][best_pstate] == 0)
- best_pstate = 0;
- get_host()->set_pstate(best_pstate); // Load our schedule
- XBT_DEBUG("Set pstate to %lu", best_pstate);
- }
-
- void post_task()
- {
- double computed_flops = sg_host_get_computed_flops(get_host()) - comp_counter;
- double target_time = (simgrid::s4u::Engine::get_clock() - start_time);
- target_time = target_time * 99.0 / 100.0; // FIXME We account for t_copy arbitrarily with 1%
- // -- this needs to be fixed
-
- bool is_initialized = rates[task_id][best_pstate] != 0;
- rates[task_id][best_pstate] = computed_flops / comp_timer;
- if (not is_initialized) {
- for (unsigned long i = 1; i < get_host()->get_pstate_count(); i++) {
- rates[task_id][i] = rates[task_id][0] * (get_host()->get_pstate_speed(i) / get_host()->get_speed());
- }
- }
-
- for (unsigned long pstate = get_host()->get_pstate_count() - 1; pstate != 0; pstate--) {
- if (computed_flops / rates[task_id][pstate] <= target_time) {
- // We just found the pstate we want to use!
- best_pstate = pstate;
- break;
- }
- }
- task_id++;
- }
-
- void update() override {}
-};
-#endif
-} // namespace simgrid::plugin::dvfs
-
-/* **************************** 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 = "dvfs-daemon-" + host.get_name();
- 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;
- if (const char* host_conf = daemon_proc->get_host()->get_property("plugin/dvfs/governor")) {
- dvfs_governor = host_conf;
- boost::algorithm::to_lower(dvfs_governor);
- } else {
- dvfs_governor = cfg_governor;
- boost::algorithm::to_lower(dvfs_governor);
- }
-
- auto governor = [&dvfs_governor, &daemon_proc]() -> std::unique_ptr<simgrid::plugin::dvfs::Governor> {
- if (dvfs_governor == "conservative")
- return std::make_unique<simgrid::plugin::dvfs::Conservative>(daemon_proc->get_host());
- if (dvfs_governor == "ondemand")
- return std::make_unique<simgrid::plugin::dvfs::OnDemand>(daemon_proc->get_host());
-#if HAVE_SMPI
- if (dvfs_governor == "adagio")
- return std::make_unique<simgrid::plugin::dvfs::Adagio>(daemon_proc->get_host());
-#endif
- if (dvfs_governor == "powersave")
- return std::make_unique<simgrid::plugin::dvfs::Powersave>(daemon_proc->get_host());
- if (dvfs_governor != "performance")
- XBT_CRITICAL("No governor specified for host %s, falling back to Performance",
- daemon_proc->get_host()->get_cname());
- return std::make_unique<simgrid::plugin::dvfs::Performance>(daemon_proc->get_host());
- }();
-
- while (true) {
- // 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->get_sampling_rate());
- governor->update();
- XBT_DEBUG("Governor (%s) just updated!", governor->get_name().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. Otherwise, the daemonize() call comes too late and
- // SMPI will take this process as an MPI process!
- daemon->daemonize();
-}
-
-/* **************************** Public interface *************************** */
-
-/**
- * @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()
-{
- static bool inited = false;
- if (inited)
- return;
- inited = true;
-
- sg_host_load_plugin_init();
-
- simgrid::s4u::Host::on_creation_cb(&on_host_added);
-}
