X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/8baff708e757b3558ed33c6f0f83d20f868751f5..950bda8fadcd13ee3bc9c33e758b6419a0bbea7a:/src/surf/plugins/host_dvfs.cpp diff --git a/src/surf/plugins/host_dvfs.cpp b/src/surf/plugins/host_dvfs.cpp index 6289449488..3daf923bcb 100644 --- a/src/surf/plugins/host_dvfs.cpp +++ b/src/surf/plugins/host_dvfs.cpp @@ -1,23 +1,14 @@ -/* Copyright (c) 2010, 2012-2018. The SimGrid Team. All rights reserved. */ +/* 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 "simgrid/simix.hpp" #include "src/plugins/vm/VirtualMachineImpl.hpp" -#include "src/surf/cpu_interface.hpp" +#include #include -#include -#include -#include -#include -#include -#include -#include -#include /** @addtogroup SURF_plugin_load @@ -27,6 +18,9 @@ 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 { @@ -34,7 +28,7 @@ namespace dvfs { class Governor { protected: - simgrid::s4u::Host* host; + simgrid::s4u::Host* const host; public: double sampling_rate; @@ -44,8 +38,8 @@ public: void init() { - const char* local_sampling_rate_config = host->getProperty("plugin/dvfs/sampling_rate"); - double global_sampling_rate_config = xbt_cfg_get_double("plugin/dvfs/sampling_rate"); + const char* local_sampling_rate_config = host->getProperty(property_sampling_rate); + double global_sampling_rate_config = xbt_cfg_get_double(property_sampling_rate); if (local_sampling_rate_config != nullptr) { sampling_rate = std::stod(local_sampling_rate_config); } else { @@ -58,6 +52,16 @@ public: 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) {} @@ -66,6 +70,16 @@ public: 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) {} @@ -74,8 +88,21 @@ public: 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 { - double freq_up_threshold = 0.95; + /** + * 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) {} @@ -83,12 +110,12 @@ public: std::string getName() override { return "OnDemand"; } void update() override { - double load = sg_host_get_current_load(host); + double load = host->getCoreCount() * sg_host_get_avg_load(host); + sg_host_load_reset(host); // Only consider the period between two calls to this method! - // FIXME I don't like that we multiply with the getCoreCount() just here... - if (load*host->getCoreCount() > freq_up_threshold) { + if (load > freq_up_threshold) { host->setPstate(0); /* Run at max. performance! */ - XBT_INFO("Load: %f > threshold: %f --> changed to pstate %i", load * host->getCoreCount(), freq_up_threshold, 0); + 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) * @@ -98,14 +125,28 @@ public: * lowest_pstate - load*pstatesCount() */ int max_pstate = host->getPstatesCount() - 1; - int new_pstate = max_pstate - load * max_pstate; + // 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); host->setPstate(new_pstate); - XBT_DEBUG("Load: %f --> changed to pstate %i", load*host->getCoreCount(), 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; @@ -116,8 +157,9 @@ public: virtual std::string getName() override { return "Conservative"; } virtual void update() override { - double load = sg_host_get_current_load(host)*host->getCoreCount(); + double load = host->getCoreCount() * sg_host_get_avg_load(host); int pstate = host->getPstate(); + sg_host_load_reset(host); // Only consider the period between two calls to this method! if (load > freq_up_threshold) { if (pstate != 0) { @@ -139,8 +181,25 @@ public: } } }; -} +/** + * Add this to your host tag: + * - + * + * 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: + * + * - + * + * This will run the update() method of the specified governor every 2 seconds + * on that host. + * + * These properties can also be used within the tag to configure + * these values globally. Using them within the will overwrite this + * global configuration + */ class HostDvfs { public: static simgrid::xbt::Extension EXTENSION_ID; @@ -156,8 +215,9 @@ HostDvfs::HostDvfs(simgrid::s4u::Host* ptr) {} HostDvfs::~HostDvfs() = default; } } +} -using simgrid::plugin::HostDvfs; +using simgrid::plugin::dvfs::HostDvfs; /* **************************** events callback *************************** */ static void on_host_added(simgrid::s4u::Host& host) @@ -165,41 +225,47 @@ static void on_host_added(simgrid::s4u::Host& host) if (dynamic_cast(&host)) // Ignore virtual machines return; - std::string name = std::string("dvfs-daemon-") + host.getCname(); - simgrid::s4u::ActorPtr daemon = simgrid::s4u::Actor::createActor(name.c_str(), &host, []() { + 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 daemonProc = simgrid::s4u::Actor::self(); + simgrid::s4u::ActorPtr daemon_proc = simgrid::s4u::Actor::self(); - XBT_DEBUG("DVFS process on %s is a daemon: %d", daemonProc->getHost()->getName().c_str(), daemonProc->isDaemon()); + 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 = daemonProc->getHost()->getProperty("plugin/dvfs/governor"); + const char* host_conf = daemon_proc->get_host()->getProperty(property_governor); if (host_conf != nullptr) { - dvfs_governor = std::string(daemonProc->getHost()->getProperty("plugin/dvfs/governor")); + dvfs_governor = std::string(daemon_proc->get_host()->getProperty(property_governor)); boost::algorithm::to_lower(dvfs_governor); } else { - dvfs_governor = xbt_cfg_get_string("plugin/dvfs/governor"); + dvfs_governor = xbt_cfg_get_string(property_governor); boost::algorithm::to_lower(dvfs_governor); } - // FIXME This is really ugly. When do we free the governor? Actually, never, because - // daemons never stop to run - they will be killed when the simulation is over. :( - simgrid::plugin::dvfs::Governor* governor; - if (dvfs_governor == "conservative") { - governor = new simgrid::plugin::dvfs::Conservative(daemonProc->getHost()); - } else if (dvfs_governor == "ondemand") { - governor = new simgrid::plugin::dvfs::OnDemand(daemonProc->getHost()); - } else if (dvfs_governor == "performance") { - governor = new simgrid::plugin::dvfs::Performance(daemonProc->getHost()); - } else if (dvfs_governor == "powersave") { - governor = new simgrid::plugin::dvfs::Powersave(daemonProc->getHost()); - } else { - XBT_CRITICAL("No governor specified for host %s", daemonProc->getHost()->getCname()); - } + auto governor = [&dvfs_governor, &daemon_proc]() { + if (dvfs_governor == "conservative") { + return std::unique_ptr( + new simgrid::plugin::dvfs::Conservative(daemon_proc->get_host())); + } else if (dvfs_governor == "ondemand") { + return std::unique_ptr( + new simgrid::plugin::dvfs::OnDemand(daemon_proc->get_host())); + } else if (dvfs_governor == "performance") { + return std::unique_ptr( + new simgrid::plugin::dvfs::Performance(daemon_proc->get_host())); + } else if (dvfs_governor == "powersave") { + return std::unique_ptr( + 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( + new simgrid::plugin::dvfs::Performance(daemon_proc->get_host())); + } + }(); while (1) { // Sleep *before* updating; important for startup (i.e., t = 0). @@ -220,7 +286,6 @@ static void on_host_added(simgrid::s4u::Host& host) } /* **************************** Public interface *************************** */ -extern "C" { /** \ingroup SURF_plugin_load * \brief Initializes the HostDvfs plugin @@ -236,9 +301,8 @@ void sg_host_dvfs_plugin_init() sg_host_load_plugin_init(); simgrid::s4u::Host::onCreation.connect(&on_host_added); - xbt_cfg_register_double("plugin/dvfs/sampling_rate", 0.1, nullptr, + xbt_cfg_register_double(property_sampling_rate, 0.1, nullptr, "How often should the dvfs plugin check whether the frequency needs to be changed?"); - xbt_cfg_register_string("plugin/dvfs/governor", "performance", nullptr, + xbt_cfg_register_string(property_governor, "performance", nullptr, "Which Governor should be used that adapts the CPU frequency?"); } -}