src/surf/ptask_L07.cpp

   1 /* Copyright (c) 2007-2021. The SimGrid Team. All rights reserved.          */
   2
   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. */
   5
   6 #include "ptask_L07.hpp"
   7 #include "src/kernel/EngineImpl.hpp"
   8 #include "src/kernel/resource/profile/Event.hpp"
   9 #include "surf/surf.hpp"
  10 #include "xbt/config.hpp"
  11
  12 #include <unordered_set>
  13
  14 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(res_host);
  15 XBT_LOG_EXTERNAL_CATEGORY(xbt_cfg);
  16
  17 /**************************************/
  18 /*** Resource Creation & Destruction **/
  19 /**************************************/
  20 void surf_host_model_init_ptask_L07()
  21 {
  22   XBT_CINFO(xbt_cfg, "Switching to the L07 model to handle parallel tasks.");
  23
  24   auto host_model = std::make_shared<simgrid::surf::HostL07Model>();
  25   simgrid::kernel::EngineImpl::get_instance()->add_model(simgrid::kernel::resource::Model::Type::HOST,
  26                                                          std::move(host_model), true);
  27 }
  28
  29 namespace simgrid {
  30 namespace surf {
  31
  32 HostL07Model::HostL07Model() : HostModel()
  33 {
  34   auto* maxmin_system = new simgrid::kernel::lmm::FairBottleneck(true /* selective update */);
  35   set_maxmin_system(maxmin_system);
  36
  37   auto net_model = std::make_shared<NetworkL07Model>(this, maxmin_system);
  38   auto engine    = simgrid::kernel::EngineImpl::get_instance();
  39   engine->add_model(simgrid::kernel::resource::Model::Type::NETWORK, std::move(net_model), true);
  40
  41   auto cpu_model = std::make_shared<CpuL07Model>(this, maxmin_system);
  42   engine->add_model(simgrid::kernel::resource::Model::Type::CPU_PM, std::move(cpu_model), true);
  43 }
  44
  45 CpuL07Model::CpuL07Model(HostL07Model* hmodel, kernel::lmm::System* sys)
  46     : CpuModel(Model::UpdateAlgo::FULL), hostModel_(hmodel)
  47 {
  48   set_maxmin_system(sys);
  49 }
  50
  51 CpuL07Model::~CpuL07Model()
  52 {
  53   set_maxmin_system(nullptr);
  54 }
  55
  56 NetworkL07Model::NetworkL07Model(HostL07Model* hmodel, kernel::lmm::System* sys)
  57     : NetworkModel(Model::UpdateAlgo::FULL), hostModel_(hmodel)
  58 {
  59   set_maxmin_system(sys);
  60   loopback_ = NetworkL07Model::create_link(
  61                   "__loopback__", std::vector<double>{simgrid::config::get_value<double>("network/loopback-bw")},
  62                   s4u::Link::SharingPolicy::FATPIPE)
  63                   ->set_latency(simgrid::config::get_value<double>("network/loopback-lat"));
  64   loopback_->seal();
  65 }
  66
  67 NetworkL07Model::~NetworkL07Model()
  68 {
  69   set_maxmin_system(nullptr);
  70 }
  71
  72 double HostL07Model::next_occurring_event(double now)
  73 {
  74   double min = HostModel::next_occurring_event_full(now);
  75   for (kernel::resource::Action const& action : *get_started_action_set()) {
  76     const auto& net_action = static_cast<const L07Action&>(action);
  77     if (net_action.get_latency() > 0 && (min < 0 || net_action.get_latency() < min)) {
  78       min = net_action.get_latency();
  79       XBT_DEBUG("Updating min with %p (start %f): %f", &net_action, net_action.get_start_time(), min);
  80     }
  81   }
  82   XBT_DEBUG("min value: %f", min);
  83
  84   return min;
  85 }
  86
  87 void HostL07Model::update_actions_state(double /*now*/, double delta)
  88 {
  89   for (auto it = std::begin(*get_started_action_set()); it != std::end(*get_started_action_set());) {
  90     auto& action = static_cast<L07Action&>(*it);
  91     ++it; // increment iterator here since the following calls to action.finish() may invalidate it
  92     if (action.get_latency() > 0) {
  93       if (action.get_latency() > delta) {
  94         action.update_latency(delta, sg_surf_precision);
  95       } else {
  96         action.set_latency(0.0);
  97       }
  98       if ((action.get_latency() <= 0.0) && (action.is_suspended() == 0)) {
  99         action.updateBound();
 100         get_maxmin_system()->update_variable_penalty(action.get_variable(), 1.0);
 101         action.set_last_update();
 102       }
 103     }
 104     XBT_DEBUG("Action (%p) : remains (%g) updated by %g.", &action, action.get_remains(),
 105               action.get_variable()->get_value() * delta);
 106     action.update_remains(action.get_variable()->get_value() * delta);
 107     action.update_max_duration(delta);
 108
 109     XBT_DEBUG("Action (%p) : remains (%g).", &action, action.get_remains());
 110
 111     /* In the next if cascade, the action can be finished either because:
 112      *  - The amount of remaining work reached 0
 113      *  - The max duration was reached
 114      * If it's not done, it may have failed.
 115      */
 116
 117     if (((action.get_remains() <= 0) && (action.get_variable()->get_penalty() > 0)) ||
 118         ((action.get_max_duration() != NO_MAX_DURATION) && (action.get_max_duration() <= 0))) {
 119       action.finish(kernel::resource::Action::State::FINISHED);
 120       continue;
 121     }
 122
 123     /* Need to check that none of the model has failed */
 124     int i                               = 0;
 125     const kernel::lmm::Constraint* cnst = action.get_variable()->get_constraint(i);
 126     while (cnst != nullptr) {
 127       i++;
 128       const kernel::resource::Resource* constraint_id = cnst->get_id();
 129       if (not constraint_id->is_on()) {
 130         XBT_DEBUG("Action (%p) Failed!!", &action);
 131         action.finish(kernel::resource::Action::State::FAILED);
 132         break;
 133       }
 134       cnst = action.get_variable()->get_constraint(i);
 135     }
 136   }
 137 }
 138
 139 kernel::resource::CpuAction* HostL07Model::execute_parallel(const std::vector<s4u::Host*>& host_list,
 140                                                             const double* flops_amount, const double* bytes_amount,
 141                                                             double rate)
 142 {
 143   return new L07Action(this, host_list, flops_amount, bytes_amount, rate);
 144 }
 145
 146 L07Action::L07Action(kernel::resource::Model* model, const std::vector<s4u::Host*>& host_list,
 147                      const double* flops_amount, const double* bytes_amount, double rate)
 148     : CpuAction(model, 1.0, false), computationAmount_(flops_amount), communicationAmount_(bytes_amount), rate_(rate)
 149 {
 150   size_t link_nb      = 0;
 151   size_t used_host_nb = 0; /* Only the hosts with something to compute (>0 flops) are counted) */
 152   double latency      = 0.0;
 153   this->set_last_update();
 154
 155   hostList_.insert(hostList_.end(), host_list.begin(), host_list.end());
 156
 157   if (flops_amount != nullptr)
 158     used_host_nb += std::count_if(flops_amount, flops_amount + host_list.size(), [](double x) { return x > 0.0; });
 159
 160   /* Compute the number of affected resources... */
 161   if (bytes_amount != nullptr) {
 162     std::unordered_set<const char*> affected_links;
 163
 164     for (size_t k = 0; k < host_list.size() * host_list.size(); k++) {
 165       if (bytes_amount[k] <= 0)
 166         continue;
 167
 168       double lat = 0.0;
 169       std::vector<kernel::resource::LinkImpl*> route;
 170       hostList_[k / host_list.size()]->route_to(hostList_[k % host_list.size()], route, &lat);
 171       latency = std::max(latency, lat);
 172
 173       for (auto const& link : route)
 174         affected_links.insert(link->get_cname());
 175     }
 176
 177     link_nb = affected_links.size();
 178   }
 179
 180   XBT_DEBUG("Creating a parallel task (%p) with %zu hosts and %zu unique links.", this, host_list.size(), link_nb);
 181   latency_ = latency;
 182
 183   set_variable(
 184       model->get_maxmin_system()->variable_new(this, 1.0, (rate > 0 ? rate : -1.0), host_list.size() + link_nb));
 185
 186   if (latency_ > 0)
 187     model->get_maxmin_system()->update_variable_penalty(get_variable(), 0.0);
 188
 189   /* Expand it for the CPUs even if there is nothing to compute, to make sure that it gets expended even if there is no
 190    * communication either */
 191   double bound = std::numeric_limits<double>::max();
 192   for (size_t i = 0; i < host_list.size(); i++) {
 193     model->get_maxmin_system()->expand(host_list[i]->pimpl_cpu->get_constraint(), get_variable(),
 194                                        (flops_amount == nullptr ? 0.0 : flops_amount[i]));
 195     if (flops_amount && flops_amount[i] > 0)
 196       bound = std::min(bound, host_list[i]->pimpl_cpu->get_speed(1.0) * host_list[i]->pimpl_cpu->get_speed_ratio() /
 197                                   flops_amount[i]);
 198   }
 199   if (bound < std::numeric_limits<double>::max())
 200     model->get_maxmin_system()->update_variable_bound(get_variable(), bound);
 201
 202   if (bytes_amount != nullptr) {
 203     for (size_t k = 0; k < host_list.size() * host_list.size(); k++) {
 204       if (bytes_amount[k] <= 0.0)
 205         continue;
 206       std::vector<kernel::resource::LinkImpl*> route;
 207       hostList_[k / host_list.size()]->route_to(hostList_[k % host_list.size()], route, nullptr);
 208
 209       for (auto const& link : route)
 210         model->get_maxmin_system()->expand_add(link->get_constraint(), this->get_variable(), bytes_amount[k]);
 211     }
 212   }
 213
 214   if (link_nb + used_host_nb == 0) {
 215     this->set_cost(1.0);
 216     this->set_remains(0.0);
 217   }
 218 }
 219
 220 kernel::resource::Action* NetworkL07Model::communicate(s4u::Host* src, s4u::Host* dst, double size, double rate)
 221 {
 222   std::vector<s4u::Host*> host_list = {src, dst};
 223   const auto* flops_amount          = new double[2]();
 224   auto* bytes_amount                = new double[4]();
 225
 226   bytes_amount[1] = size;
 227
 228   kernel::resource::Action* res = hostModel_->execute_parallel(host_list, flops_amount, bytes_amount, rate);
 229   static_cast<L07Action*>(res)->free_arrays_ = true;
 230   return res;
 231 }
 232
 233 kernel::resource::Cpu* CpuL07Model::create_cpu(s4u::Host* host, const std::vector<double>& speed_per_pstate)
 234 {
 235   return (new CpuL07(host, speed_per_pstate))->set_model(this);
 236 }
 237
 238 kernel::resource::LinkImpl* NetworkL07Model::create_link(const std::string& name, const std::vector<double>& bandwidths,
 239                                                          s4u::Link::SharingPolicy policy)
 240 {
 241   xbt_assert(bandwidths.size() == 1, "Non WIFI link must have only 1 bandwidth.");
 242   auto link = new LinkL07(name, bandwidths[0], policy, get_maxmin_system());
 243   link->set_model(this);
 244   return link;
 245 }
 246
 247 /************
 248  * Resource *
 249  ************/
 250
 251 kernel::resource::CpuAction* CpuL07::execution_start(double size)
 252 {
 253   std::vector<s4u::Host*> host_list = {get_iface()};
 254
 255   auto* flops_amount = new double[host_list.size()]();
 256   flops_amount[0]    = size;
 257
 258   kernel::resource::CpuAction* res =
 259       static_cast<CpuL07Model*>(get_model())->hostModel_->execute_parallel(host_list, flops_amount, nullptr, -1);
 260   static_cast<L07Action*>(res)->free_arrays_ = true;
 261   return res;
 262 }
 263
 264 kernel::resource::CpuAction* CpuL07::sleep(double duration)
 265 {
 266   auto* action = static_cast<L07Action*>(execution_start(1.0));
 267   action->set_max_duration(duration);
 268   action->set_suspend_state(kernel::resource::Action::SuspendStates::SLEEPING);
 269   get_model()->get_maxmin_system()->update_variable_penalty(action->get_variable(), 0.0);
 270
 271   return action;
 272 }
 273
 274 bool CpuL07::is_used() const
 275 {
 276   return get_model()->get_maxmin_system()->constraint_used(get_constraint());
 277 }
 278
 279 /** @brief take into account changes of speed (either load or max) */
 280 void CpuL07::on_speed_change()
 281 {
 282   const kernel::lmm::Variable* var;
 283   const kernel::lmm::Element* elem = nullptr;
 284
 285   get_model()->get_maxmin_system()->update_constraint_bound(get_constraint(), speed_.peak * speed_.scale);
 286   while ((var = get_constraint()->get_variable(&elem))) {
 287     const kernel::resource::Action* action = var->get_id();
 288
 289     get_model()->get_maxmin_system()->update_variable_bound(action->get_variable(), speed_.scale * speed_.peak);
 290   }
 291
 292   Cpu::on_speed_change();
 293 }
 294
 295 LinkL07::LinkL07(const std::string& name, double bandwidth, s4u::Link::SharingPolicy policy,
 296                  kernel::lmm::System* system)
 297     : LinkImpl(name)
 298 {
 299   this->set_constraint(system->constraint_new(this, bandwidth));
 300   bandwidth_.peak = bandwidth;
 301
 302   if (policy == s4u::Link::SharingPolicy::FATPIPE)
 303     get_constraint()->unshare();
 304 }
 305
 306 bool LinkL07::is_used() const
 307 {
 308   return get_model()->get_maxmin_system()->constraint_used(get_constraint());
 309 }
 310
 311 void CpuL07::apply_event(kernel::profile::Event* triggered, double value)
 312 {
 313   XBT_DEBUG("Updating cpu %s (%p) with value %g", get_cname(), this, value);
 314   if (triggered == speed_.event) {
 315     speed_.scale = value;
 316     on_speed_change();
 317     tmgr_trace_event_unref(&speed_.event);
 318
 319   } else if (triggered == state_event_) {
 320     if (value > 0) {
 321       if (not is_on()) {
 322         XBT_VERB("Restart actors on host %s", get_iface()->get_cname());
 323         get_iface()->turn_on();
 324       }
 325     } else
 326       get_iface()->turn_off();
 327     tmgr_trace_event_unref(&state_event_);
 328
 329   } else {
 330     xbt_die("Unknown event!\n");
 331   }
 332 }
 333
 334 void LinkL07::apply_event(kernel::profile::Event* triggered, double value)
 335 {
 336   XBT_DEBUG("Updating link %s (%p) with value=%f", get_cname(), this, value);
 337   if (triggered == bandwidth_.event) {
 338     set_bandwidth(value);
 339     tmgr_trace_event_unref(&bandwidth_.event);
 340
 341   } else if (triggered == latency_.event) {
 342     set_latency(value);
 343     tmgr_trace_event_unref(&latency_.event);
 344
 345   } else if (triggered == state_event_) {
 346     if (value > 0)
 347       turn_on();
 348     else
 349       turn_off();
 350     tmgr_trace_event_unref(&state_event_);
 351
 352   } else {
 353     xbt_die("Unknown event ! \n");
 354   }
 355 }
 356
 357 void LinkL07::set_bandwidth(double value)
 358 {
 359   bandwidth_.peak = value;
 360   LinkImpl::on_bandwidth_change();
 361
 362   get_model()->get_maxmin_system()->update_constraint_bound(get_constraint(), bandwidth_.peak * bandwidth_.scale);
 363 }
 364
 365 kernel::resource::LinkImpl* LinkL07::set_latency(double value)
 366 {
 367   latency_check(value);
 368   const kernel::lmm::Variable* var;
 369   L07Action* action;
 370   const kernel::lmm::Element* elem = nullptr;
 371
 372   latency_.peak = value;
 373   while ((var = get_constraint()->get_variable(&elem))) {
 374     action = static_cast<L07Action*>(var->get_id());
 375     action->updateBound();
 376   }
 377   return this;
 378 }
 379 LinkL07::~LinkL07() = default;
 380
 381 /**********
 382  * Action *
 383  **********/
 384
 385 L07Action::~L07Action()
 386 {
 387   if (free_arrays_) {
 388     delete[] computationAmount_;
 389     delete[] communicationAmount_;
 390   }
 391 }
 392
 393 void L07Action::updateBound()
 394 {
 395   double lat_current = 0.0;
 396
 397   size_t host_count = hostList_.size();
 398
 399   if (communicationAmount_ != nullptr) {
 400     for (size_t i = 0; i < host_count; i++) {
 401       for (size_t j = 0; j < host_count; j++) {
 402         if (communicationAmount_[i * host_count + j] > 0) {
 403           double lat = 0.0;
 404           std::vector<kernel::resource::LinkImpl*> route;
 405           hostList_.at(i)->route_to(hostList_.at(j), route, &lat);
 406
 407           lat_current = std::max(lat_current, lat * communicationAmount_[i * host_count + j]);
 408         }
 409       }
 410     }
 411   }
 412   double lat_bound = kernel::resource::NetworkModel::cfg_tcp_gamma / (2.0 * lat_current);
 413   XBT_DEBUG("action (%p) : lat_bound = %g", this, lat_bound);
 414   if ((latency_ <= 0.0) && is_running()) {
 415     if (rate_ < 0)
 416       get_model()->get_maxmin_system()->update_variable_bound(get_variable(), lat_bound);
 417     else
 418       get_model()->get_maxmin_system()->update_variable_bound(get_variable(), std::min(rate_, lat_bound));
 419   }
 420 }
 421
 422 } // namespace surf
 423 } // namespace simgrid