1 /* Copyright (c) 2006-2016. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 #include "simdag_private.hpp"
8 #include "src/surf/HostImpl.hpp"
9 #include "src/surf/surf_interface.hpp"
11 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(sd_task, sd, "Logging specific to SimDag (task)");
13 /* Destroys the data memorized by SD_task_schedule. Task state must be SD_SCHEDULED or SD_RUNNABLE. */
14 static void __SD_task_destroy_scheduling_data(SD_task_t task)
16 if (task->state != SD_SCHEDULED && task->state != SD_RUNNABLE)
17 THROWF(arg_error, 0, "Task '%s' must be SD_SCHEDULED or SD_RUNNABLE", SD_task_get_name(task));
19 xbt_free(task->flops_amount);
20 xbt_free(task->bytes_amount);
21 task->bytes_amount = nullptr;
22 task->flops_amount = nullptr;
26 * \brief Creates a new task.
28 * \param name the name of the task (can be \c nullptr)
29 * \param data the user data you want to associate with the task (can be \c nullptr)
30 * \param amount amount of the task
31 * \return the new task
32 * \see SD_task_destroy()
34 SD_task_t SD_task_create(const char *name, void *data, double amount)
36 SD_task_t task = xbt_new0(s_SD_task_t, 1);
37 task->kind = SD_TASK_NOT_TYPED;
38 task->state= SD_NOT_SCHEDULED;
39 sd_global->initial_tasks->insert(task);
42 task->start_time = -1.0;
43 task->finish_time = -1.0;
44 task->surf_action = nullptr;
45 task->watch_points = 0;
47 task->inputs = new std::set<SD_task_t>();
48 task->outputs = new std::set<SD_task_t>();
49 task->predecessors = new std::set<SD_task_t>();
50 task->successors = new std::set<SD_task_t>();
53 task->name = std::string(name);
54 task->amount = amount;
55 task->allocation = new std::vector<sg_host_t>();
60 static inline SD_task_t SD_task_create_sized(const char *name, void *data, double amount, int count)
62 SD_task_t task = SD_task_create(name, data, amount);
63 task->bytes_amount = xbt_new0(double, count * count);
64 task->flops_amount = xbt_new0(double, count);
68 /** @brief create a end-to-end communication task that can then be auto-scheduled
70 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
71 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
74 * A end-to-end communication must be scheduled on 2 hosts, and the amount specified at creation is sent from hosts[0]
77 SD_task_t SD_task_create_comm_e2e(const char *name, void *data, double amount)
79 SD_task_t res = SD_task_create_sized(name, data, amount, 2);
80 res->bytes_amount[2] = amount;
81 res->kind = SD_TASK_COMM_E2E;
86 /** @brief create a sequential computation task that can then be auto-scheduled
88 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
89 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
92 * A sequential computation must be scheduled on 1 host, and the amount specified at creation to be run on hosts[0].
94 * \param name the name of the task (can be \c nullptr)
95 * \param data the user data you want to associate with the task (can be \c nullptr)
96 * \param flops_amount amount of compute work to be done by the task
97 * \return the new SD_TASK_COMP_SEQ typed task
99 SD_task_t SD_task_create_comp_seq(const char *name, void *data, double flops_amount)
101 SD_task_t res = SD_task_create_sized(name, data, flops_amount, 1);
102 res->flops_amount[0] = flops_amount;
103 res->kind = SD_TASK_COMP_SEQ;
108 /** @brief create a parallel computation task that can then be auto-scheduled
110 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
111 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
114 * A parallel computation can be scheduled on any number of host.
115 * The underlying speedup model is Amdahl's law.
116 * To be auto-scheduled, \see SD_task_distribute_comp_amdahl has to be called first.
117 * \param name the name of the task (can be \c nullptr)
118 * \param data the user data you want to associate with the task (can be \c nullptr)
119 * \param flops_amount amount of compute work to be done by the task
120 * \param alpha purely serial fraction of the work to be done (in [0.;1.[)
121 * \return the new task
123 SD_task_t SD_task_create_comp_par_amdahl(const char *name, void *data, double flops_amount, double alpha)
125 xbt_assert(alpha < 1. && alpha >= 0., "Invalid parameter: alpha must be in [0.;1.[");
127 SD_task_t res = SD_task_create(name, data, flops_amount);
129 res->kind = SD_TASK_COMP_PAR_AMDAHL;
134 /** @brief create a complex data redistribution task that can then be auto-scheduled
136 * Auto-scheduling mean that the task can be used with SD_task_schedulev().
137 * This allows to specify the task costs at creation, and decouple them from the scheduling process where you just
138 * specify which resource should communicate.
140 * A data redistribution can be scheduled on any number of host.
141 * The assumed distribution is a 1D block distribution. Each host owns the same share of the \see amount.
142 * To be auto-scheduled, \see SD_task_distribute_comm_mxn_1d_block has to be called first.
143 * \param name the name of the task (can be \c nullptr)
144 * \param data the user data you want to associate with the task (can be \c nullptr)
145 * \param amount amount of data to redistribute by the task
146 * \return the new task
148 SD_task_t SD_task_create_comm_par_mxn_1d_block(const char *name, void *data, double amount)
150 SD_task_t res = SD_task_create(name, data, amount);
151 res->kind = SD_TASK_COMM_PAR_MXN_1D_BLOCK;
157 * \brief Destroys a task.
159 * The user data (if any) should have been destroyed first.
161 * \param task the task you want to destroy
162 * \see SD_task_create()
164 void SD_task_destroy(SD_task_t task)
166 XBT_DEBUG("Destroying task %s...", SD_task_get_name(task));
168 /* First Remove all dependencies associated with the task. */
169 while (!task->predecessors->empty())
170 SD_task_dependency_remove(*(task->predecessors->begin()), task);
171 while (!task->inputs->empty())
172 SD_task_dependency_remove(*(task->inputs->begin()), task);
173 while (!task->successors->empty())
174 SD_task_dependency_remove(task, *(task->successors->begin()));
175 while (!task->outputs->empty())
176 SD_task_dependency_remove(task, *(task->outputs->begin()));
178 if (task->state == SD_SCHEDULED || task->state == SD_RUNNABLE)
179 __SD_task_destroy_scheduling_data(task);
181 if (task->surf_action != nullptr)
182 task->surf_action->unref();
184 delete task->allocation;
185 xbt_free(task->bytes_amount);
186 xbt_free(task->flops_amount);
188 delete task->outputs;
189 delete task->predecessors;
190 delete task->successors;
193 XBT_DEBUG("Task destroyed.");
197 * \brief Returns the user data of a task
200 * \return the user data associated with this task (can be \c nullptr)
201 * \see SD_task_set_data()
203 void *SD_task_get_data(SD_task_t task)
209 * \brief Sets the user data of a task
211 * The new data can be \c nullptr. The old data should have been freed first, if it was not \c nullptr.
214 * \param data the new data you want to associate with this task
215 * \see SD_task_get_data()
217 void SD_task_set_data(SD_task_t task, void *data)
223 * \brief Sets the rate of a task
225 * This will change the network bandwidth a task can use. This rate cannot be dynamically changed. Once the task has
226 * started, this call is ineffective. This rate depends on both the nominal bandwidth on the route onto which the task
227 * is scheduled (\see SD_task_get_current_bandwidth) and the amount of data to transfer.
229 * To divide the nominal bandwidth by 2, the rate then has to be :
230 * rate = bandwidth/(2*amount)
232 * \param task a \see SD_TASK_COMM_E2E task (end-to-end communication)
233 * \param rate the new rate you want to associate with this task.
235 void SD_task_set_rate(SD_task_t task, double rate)
237 xbt_assert(task->kind == SD_TASK_COMM_E2E, "The rate can be modified for end-to-end communications only.");
238 if(task->state < SD_RUNNING) {
241 XBT_WARN("Task %p has started. Changing rate is ineffective.", task);
246 * \brief Returns the state of a task
249 * \return the current \ref e_SD_task_state_t "state" of this task:
250 * #SD_NOT_SCHEDULED, #SD_SCHEDULED, #SD_RUNNABLE, #SD_RUNNING, #SD_DONE or #SD_FAILED
251 * \see e_SD_task_state_t
253 e_SD_task_state_t SD_task_get_state(SD_task_t task)
258 /* Changes the state of a task. Updates the sd_global->watch_point_reached flag.
260 void SD_task_set_state(SD_task_t task, e_SD_task_state_t new_state)
262 std::set<SD_task_t>::iterator idx;
263 XBT_DEBUG("Set state of '%s' to %d", task->name.c_str(), new_state);
264 if ((new_state == SD_NOT_SCHEDULED || new_state == SD_SCHEDULABLE) && task->state == SD_FAILED){
265 sd_global->completed_tasks->erase(task);
266 sd_global->initial_tasks->insert(task);
269 if (new_state == SD_SCHEDULED && task->state == SD_RUNNABLE){
270 sd_global->initial_tasks->insert(task);
271 sd_global->runnable_tasks->erase(task);
274 if (new_state == SD_RUNNABLE){
275 idx = sd_global->initial_tasks->find(task);
276 if (idx != sd_global->initial_tasks->end()) {
277 sd_global->runnable_tasks->insert(*idx);
278 sd_global->initial_tasks->erase(idx);
282 if (new_state == SD_RUNNING)
283 sd_global->runnable_tasks->erase(task);
285 if (new_state == SD_DONE || new_state == SD_FAILED){
286 sd_global->completed_tasks->insert(task);
287 task->start_time = task->surf_action->getStartTime();
288 if (new_state == SD_DONE){
289 task->finish_time = task->surf_action->getFinishTime();
291 jedule_log_sd_event(task);
294 task->finish_time = surf_get_clock();
295 task->surf_action->unref();
296 task->surf_action = nullptr;
297 task->allocation->clear();
300 task->state = new_state;
302 if (task->watch_points & new_state) {
303 XBT_VERB("Watch point reached with task '%s'!", task->name.c_str());
304 sd_global->watch_point_reached = true;
305 SD_task_unwatch(task, new_state); /* remove the watch point */
310 * \brief Returns the name of a task
313 * \return the name of this task (can be \c nullptr)
315 const char *SD_task_get_name(SD_task_t task)
317 return task->name.c_str();
320 /** @brief Allows to change the name of a task */
321 void SD_task_set_name(SD_task_t task, const char *name)
323 task->name = std::string(name);
326 /** @brief Returns the dynar of the parents of a task
329 * \return a newly allocated dynar comprising the parents of this task
332 xbt_dynar_t SD_task_get_parents(SD_task_t task)
334 xbt_dynar_t parents = xbt_dynar_new(sizeof(SD_task_t), nullptr);
336 for (auto it : *task->predecessors)
337 xbt_dynar_push(parents, &it);
338 for (auto it : *task->inputs)
339 xbt_dynar_push(parents, &it);
344 /** @brief Returns the dynar of the parents of a task
347 * \return a newly allocated dynar comprising the parents of this task
349 xbt_dynar_t SD_task_get_children(SD_task_t task)
351 xbt_dynar_t children = xbt_dynar_new(sizeof(SD_task_t), nullptr);
353 for (auto it : *task->successors)
354 xbt_dynar_push(children, &it);
355 for (auto it : *task->outputs)
356 xbt_dynar_push(children, &it);
362 * \brief Returns the number of workstations involved in a task
364 * Only call this on already scheduled tasks!
367 int SD_task_get_workstation_count(SD_task_t task)
369 return task->allocation->size();
373 * \brief Returns the list of workstations involved in a task
375 * Only call this on already scheduled tasks!
378 sg_host_t *SD_task_get_workstation_list(SD_task_t task)
380 return &(*(task->allocation))[0];
384 * \brief Returns the total amount of work contained in a task
387 * \return the total amount of work (computation or data transfer) for this task
388 * \see SD_task_get_remaining_amount()
390 double SD_task_get_amount(SD_task_t task)
395 /** @brief Sets the total amount of work of a task
396 * For sequential typed tasks (COMP_SEQ and COMM_E2E), it also sets the appropriate values in the flops_amount and
397 * bytes_amount arrays respectively. Nothing more than modifying task->amount is done for parallel typed tasks
398 * (COMP_PAR_AMDAHL and COMM_PAR_MXN_1D_BLOCK) as the distribution of the amount of work is done at scheduling time.
401 * \param amount the new amount of work to execute
403 void SD_task_set_amount(SD_task_t task, double amount)
405 task->amount = amount;
406 if (task->kind == SD_TASK_COMP_SEQ)
407 task->flops_amount[0] = amount;
408 if (task->kind == SD_TASK_COMM_E2E)
409 task->bytes_amount[2] = amount;
413 * \brief Returns the alpha parameter of a SD_TASK_COMP_PAR_AMDAHL task
415 * \param task a parallel task assuming Amdahl's law as speedup model
416 * \return the alpha parameter (serial part of a task in percent) for this task
418 double SD_task_get_alpha(SD_task_t task)
420 xbt_assert(SD_task_get_kind(task) == SD_TASK_COMP_PAR_AMDAHL, "Alpha parameter is not defined for this kind of task");
425 * \brief Returns the remaining amount work to do till the completion of a task
428 * \return the remaining amount of work (computation or data transfer) of this task
429 * \see SD_task_get_amount()
431 double SD_task_get_remaining_amount(SD_task_t task)
433 if (task->surf_action)
434 return task->surf_action->getRemains();
436 return (task->state == SD_DONE) ? 0 : task->amount;
439 e_SD_task_kind_t SD_task_get_kind(SD_task_t task)
444 /** @brief Displays debugging information about a task */
445 void SD_task_dump(SD_task_t task)
447 XBT_INFO("Displaying task %s", SD_task_get_name(task));
448 if (task->state == SD_RUNNABLE)
449 XBT_INFO(" - state: runnable");
450 else if (task->state < SD_RUNNABLE)
451 XBT_INFO(" - state: %s not runnable", __get_state_name(task->state));
453 XBT_INFO(" - state: not runnable %s", __get_state_name(task->state));
455 if (task->kind != 0) {
456 switch (task->kind) {
457 case SD_TASK_COMM_E2E:
458 XBT_INFO(" - kind: end-to-end communication");
460 case SD_TASK_COMP_SEQ:
461 XBT_INFO(" - kind: sequential computation");
463 case SD_TASK_COMP_PAR_AMDAHL:
464 XBT_INFO(" - kind: parallel computation following Amdahl's law");
466 case SD_TASK_COMM_PAR_MXN_1D_BLOCK:
467 XBT_INFO(" - kind: MxN data redistribution assuming 1D block distribution");
470 XBT_INFO(" - (unknown kind %d)", task->kind);
474 XBT_INFO(" - amount: %.0f", SD_task_get_amount(task));
475 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
476 XBT_INFO(" - alpha: %.2f", task->alpha);
477 XBT_INFO(" - Dependencies to satisfy: %zu", task->inputs->size()+ task->predecessors->size());
478 if ((task->inputs->size()+ task->predecessors->size()) > 0) {
479 XBT_INFO(" - pre-dependencies:");
480 for (auto it : *task->predecessors)
481 XBT_INFO(" %s", it->name.c_str());
483 for (auto it: *task->inputs)
484 XBT_INFO(" %s", it->name.c_str());
486 if ((task->outputs->size() + task->successors->size()) > 0) {
487 XBT_INFO(" - post-dependencies:");
489 for (auto it : *task->successors)
490 XBT_INFO(" %s", it->name.c_str());
491 for (auto it : *task->outputs)
492 XBT_INFO(" %s", it->name.c_str());
496 /** @brief Dumps the task in dotty formalism into the FILE* passed as second argument */
497 void SD_task_dotty(SD_task_t task, void *out)
499 FILE *fout = static_cast<FILE*>(out);
500 fprintf(fout, " T%p [label=\"%.20s\"", task, task->name.c_str());
501 switch (task->kind) {
502 case SD_TASK_COMM_E2E:
503 case SD_TASK_COMM_PAR_MXN_1D_BLOCK:
504 fprintf(fout, ", shape=box");
506 case SD_TASK_COMP_SEQ:
507 case SD_TASK_COMP_PAR_AMDAHL:
508 fprintf(fout, ", shape=circle");
511 xbt_die("Unknown task type!");
513 fprintf(fout, "];\n");
514 for (auto it : *task->predecessors)
515 fprintf(fout, " T%p -> T%p;\n", it, task);
516 for (auto it : *task->inputs)
517 fprintf(fout, " T%p -> T%p;\n", it, task);
521 * \brief Adds a dependency between two tasks
523 * \a dst will depend on \a src, ie \a dst will not start before \a src is finished.
524 * Their \ref e_SD_task_state_t "state" must be #SD_NOT_SCHEDULED, #SD_SCHEDULED or #SD_RUNNABLE.
526 * \param name the name of the new dependency (can be \c nullptr)
527 * \param data the user data you want to associate with this dependency (can be \c nullptr)
528 * \param src the task which must be executed first
529 * \param dst the task you want to make depend on \a src
530 * \see SD_task_dependency_remove()
532 void SD_task_dependency_add(const char *name, void *data, SD_task_t src, SD_task_t dst)
535 THROWF(arg_error, 0, "Cannot add a dependency between task '%s' and itself", SD_task_get_name(src));
537 if (src->state == SD_DONE || src->state == SD_FAILED)
538 THROWF(arg_error, 0, "Task '%s' must be SD_NOT_SCHEDULED, SD_SCHEDULABLE, SD_SCHEDULED, SD_RUNNABLE, or SD_RUNNING",
541 if (dst->state == SD_DONE || dst->state == SD_FAILED || dst->state == SD_RUNNING)
542 THROWF(arg_error, 0, "Task '%s' must be SD_NOT_SCHEDULED, SD_SCHEDULABLE, SD_SCHEDULED, or SD_RUNNABLE",
545 if (dst->inputs->find(src) != dst->inputs->end() || src->outputs->find(dst) != src->outputs->end() ||
546 src->successors->find(dst) != src->successors->end() || dst->predecessors->find(src) != dst->predecessors->end())
547 THROWF(arg_error, 0, "A dependency already exists between task '%s' and task '%s'", src->name.c_str(), dst->name.c_str());
549 XBT_DEBUG("SD_task_dependency_add: src = %s, dst = %s", src->name.c_str(), dst->name.c_str());
551 if (src->kind == SD_TASK_COMM_E2E || src->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK){
552 if (dst->kind == SD_TASK_COMP_SEQ || dst->kind == SD_TASK_COMP_PAR_AMDAHL)
553 dst->inputs->insert(src);
555 dst->predecessors->insert(src);
556 src->successors->insert(dst);
558 if (dst->kind == SD_TASK_COMM_E2E|| dst->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK)
559 src->outputs->insert(dst);
561 src->successors->insert(dst);
562 dst->predecessors->insert(src);
565 /* if the task was runnable, the task goes back to SD_SCHEDULED because of the new dependency*/
566 if (dst->state == SD_RUNNABLE) {
567 XBT_DEBUG("SD_task_dependency_add: %s was runnable and becomes scheduled!", dst->name.c_str());
568 SD_task_set_state(dst, SD_SCHEDULED);
573 * \brief Indicates whether there is a dependency between two tasks.
576 * \param dst a task depending on \a src
578 * If src is nullptr, checks whether dst has any pre-dependency.
579 * If dst is nullptr, checks whether src has any post-dependency.
581 int SD_task_dependency_exists(SD_task_t src, SD_task_t dst)
583 xbt_assert(src != nullptr || dst != nullptr, "Invalid parameter: both src and dst are nullptr");
587 return (src->successors->find(dst) != src->successors->end() || src->outputs->find(dst) != src->outputs->end());
589 return src->successors->size() + src->outputs->size();
592 return dst->predecessors->size() + dst->inputs->size();
598 * \brief Remove a dependency between two tasks
601 * \param dst a task depending on \a src
602 * \see SD_task_dependency_add()
604 void SD_task_dependency_remove(SD_task_t src, SD_task_t dst)
606 XBT_DEBUG("SD_task_dependency_remove: src = %s, dst = %s", SD_task_get_name(src), SD_task_get_name(dst));
608 if (src->successors->find(dst) == src->successors->end() && src->outputs->find(dst) == src->outputs->end())
609 THROWF(arg_error, 0, "No dependency found between task '%s' and '%s': task '%s' is not a successor of task '%s'",
610 src->name.c_str(), dst->name.c_str(), dst->name.c_str(), src->name.c_str());
612 if (src->kind == SD_TASK_COMM_E2E || src->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK){
613 if (dst->kind == SD_TASK_COMP_SEQ || dst->kind == SD_TASK_COMP_PAR_AMDAHL)
614 dst->inputs->erase(src);
616 dst->predecessors->erase(src);
617 src->successors->erase(dst);
619 if (dst->kind == SD_TASK_COMM_E2E|| dst->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK)
620 src->outputs->erase(dst);
622 src->successors->erase(dst);
623 dst->predecessors->erase(src);
626 /* if the task was scheduled and dependencies are satisfied, we can make it runnable */
627 if (dst->predecessors->empty() && dst->inputs->empty() && dst->state == SD_SCHEDULED)
628 SD_task_set_state(dst, SD_RUNNABLE);
632 * \brief Adds a watch point to a task
634 * SD_simulate() will stop as soon as the \ref e_SD_task_state_t "state" of this task becomes the one given in argument.
635 * The watch point is then automatically removed.
638 * \param state the \ref e_SD_task_state_t "state" you want to watch (cannot be #SD_NOT_SCHEDULED)
639 * \see SD_task_unwatch()
641 void SD_task_watch(SD_task_t task, e_SD_task_state_t state)
643 if (state & SD_NOT_SCHEDULED)
644 THROWF(arg_error, 0, "Cannot add a watch point for state SD_NOT_SCHEDULED");
646 task->watch_points = task->watch_points | state;
650 * \brief Removes a watch point from a task
653 * \param state the \ref e_SD_task_state_t "state" you no longer want to watch
654 * \see SD_task_watch()
656 void SD_task_unwatch(SD_task_t task, e_SD_task_state_t state)
658 xbt_assert(state != SD_NOT_SCHEDULED, "SimDag error: Cannot have a watch point for state SD_NOT_SCHEDULED");
659 task->watch_points = task->watch_points & ~state;
663 * \brief Returns an approximative estimation of the execution time of a task.
665 * The estimation is very approximative because the value returned is the time the task would take if it was executed
666 * now and if it was the only task.
668 * \param task the task to evaluate
669 * \param host_count number of hosts on which the task would be executed
670 * \param host_list the hosts on which the task would be executed
671 * \param flops_amount computation amount for each host(i.e., an array of host_count doubles)
672 * \param bytes_amount communication amount between each pair of hosts (i.e., a matrix of host_count*host_count doubles)
675 double SD_task_get_execution_time(SD_task_t task, int host_count, const sg_host_t *host_list,
676 const double *flops_amount, const double *bytes_amount)
678 xbt_assert(host_count > 0, "Invalid parameter");
679 double max_time = 0.0;
681 /* the task execution time is the maximum execution time of the parallel tasks */
682 for (int i = 0; i < host_count; i++) {
684 if (flops_amount != nullptr)
685 time = flops_amount[i] / host_list[i]->speed();
687 if (bytes_amount != nullptr)
688 for (int j = 0; j < host_count; j++)
689 if (bytes_amount[i * host_count + j] != 0)
690 time += (SD_route_get_latency(host_list[i], host_list[j]) +
691 bytes_amount[i * host_count + j] / SD_route_get_bandwidth(host_list[i], host_list[j]));
699 static inline void SD_task_do_schedule(SD_task_t task)
701 if (SD_task_get_state(task) > SD_SCHEDULABLE)
702 THROWF(arg_error, 0, "Task '%s' has already been scheduled", SD_task_get_name(task));
704 if (task->predecessors->empty() && task->inputs->empty())
705 SD_task_set_state(task, SD_RUNNABLE);
707 SD_task_set_state(task, SD_SCHEDULED);
711 * \brief Schedules a task
713 * The task state must be #SD_NOT_SCHEDULED.
714 * Once scheduled, a task is executed as soon as possible in \see SD_simulate, i.e. when its dependencies are satisfied.
716 * \param task the task you want to schedule
717 * \param host_count number of hosts on which the task will be executed
718 * \param workstation_list the hosts on which the task will be executed
719 * \param flops_amount computation amount for each hosts (i.e., an array of host_count doubles)
720 * \param bytes_amount communication amount between each pair of hosts (i.e., a matrix of host_count*host_count doubles)
721 * \param rate task execution speed rate
722 * \see SD_task_unschedule()
724 void SD_task_schedule(SD_task_t task, int host_count, const sg_host_t * host_list,
725 const double *flops_amount, const double *bytes_amount, double rate)
727 xbt_assert(host_count > 0, "host_count must be positive");
732 task->flops_amount = static_cast<double*>(xbt_realloc(task->flops_amount, sizeof(double) * host_count));
733 memcpy(task->flops_amount, flops_amount, sizeof(double) * host_count);
735 xbt_free(task->flops_amount);
736 task->flops_amount = nullptr;
739 int communication_nb = host_count * host_count;
741 task->bytes_amount = static_cast<double*>(xbt_realloc(task->bytes_amount, sizeof(double) * communication_nb));
742 memcpy(task->bytes_amount, bytes_amount, sizeof(double) * communication_nb);
744 xbt_free(task->bytes_amount);
745 task->bytes_amount = nullptr;
748 for(int i =0; i<host_count; i++)
749 task->allocation->push_back(host_list[i]);
751 SD_task_do_schedule(task);
755 * \brief Unschedules a task
757 * The task state must be #SD_SCHEDULED, #SD_RUNNABLE, #SD_RUNNING or #SD_FAILED.
758 * If you call this function, the task state becomes #SD_NOT_SCHEDULED.
759 * Call SD_task_schedule() to schedule it again.
761 * \param task the task you want to unschedule
762 * \see SD_task_schedule()
764 void SD_task_unschedule(SD_task_t task)
766 if (task->state == SD_NOT_SCHEDULED || task->state == SD_SCHEDULABLE)
767 THROWF(arg_error, 0, "Task %s: the state must be SD_SCHEDULED, SD_RUNNABLE, SD_RUNNING or SD_FAILED", task->name.c_str());
769 if ((task->state == SD_SCHEDULED || task->state == SD_RUNNABLE) /* if the task is scheduled or runnable */
770 && ((task->kind == SD_TASK_COMP_PAR_AMDAHL) || (task->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK))) {
771 /* Don't free scheduling data for typed tasks */
772 __SD_task_destroy_scheduling_data(task);
773 task->allocation->clear();
776 if (SD_task_get_state(task) == SD_RUNNING)
777 /* the task should become SD_FAILED */
778 task->surf_action->cancel();
780 if (task->predecessors->empty() && task->inputs->empty())
781 SD_task_set_state(task, SD_SCHEDULABLE);
783 SD_task_set_state(task, SD_NOT_SCHEDULED);
785 task->start_time = -1.0;
789 void SD_task_run(SD_task_t task)
791 xbt_assert(task->state == SD_RUNNABLE, "Task '%s' is not runnable! Task state: %d", task->name.c_str(), (int) task->state);
792 xbt_assert(task->allocation != nullptr, "Task '%s': host_list is nullptr!", task->name.c_str());
794 XBT_VERB("Executing task '%s'", task->name.c_str());
796 /* Copy the elements of the task into the action */
797 int host_nb = task->allocation->size();
798 sg_host_t *hosts = xbt_new(sg_host_t, host_nb);
800 for (auto host: *task->allocation){
805 double *flops_amount = xbt_new0(double, host_nb);
806 double *bytes_amount = xbt_new0(double, host_nb * host_nb);
808 if(task->flops_amount)
809 memcpy(flops_amount, task->flops_amount, sizeof(double) * host_nb);
810 if(task->bytes_amount)
811 memcpy(bytes_amount, task->bytes_amount, sizeof(double) * host_nb * host_nb);
813 task->surf_action = surf_host_model->executeParallelTask(host_nb, hosts, flops_amount, bytes_amount, task->rate);
815 task->surf_action->setData(task);
817 XBT_DEBUG("surf_action = %p", task->surf_action);
819 __SD_task_destroy_scheduling_data(task); /* now the scheduling data are not useful anymore */
820 SD_task_set_state(task, SD_RUNNING);
821 sd_global->return_set->insert(task);
825 * \brief Returns the start time of a task
827 * The task state must be SD_RUNNING, SD_DONE or SD_FAILED.
829 * \param task: a task
830 * \return the start time of this task
832 double SD_task_get_start_time(SD_task_t task)
834 if (task->surf_action)
835 return task->surf_action->getStartTime();
837 return task->start_time;
841 * \brief Returns the finish time of a task
843 * The task state must be SD_RUNNING, SD_DONE or SD_FAILED.
844 * If the state is not completed yet, the returned value is an estimation of the task finish time. This value can
845 * vary until the task is completed.
847 * \param task: a task
848 * \return the start time of this task
850 double SD_task_get_finish_time(SD_task_t task)
852 if (task->surf_action) /* should never happen as actions are destroyed right after their completion */
853 return task->surf_action->getFinishTime();
855 return task->finish_time;
858 void SD_task_distribute_comp_amdahl(SD_task_t task, int count)
860 xbt_assert(task->kind == SD_TASK_COMP_PAR_AMDAHL, "Task %s is not a SD_TASK_COMP_PAR_AMDAHL typed task."
861 "Cannot use this function.", task->name.c_str());
862 task->flops_amount = xbt_new0(double, count);
863 task->bytes_amount = xbt_new0(double, count * count);
865 for (int i=0; i<count; i++){
866 task->flops_amount[i] = (task->alpha + (1 - task->alpha)/count) * task->amount;
870 void SD_task_build_MxN_1D_block_matrix(SD_task_t task, int src_nb, int dst_nb){
871 xbt_assert(task->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK, "Task %s is not a SD_TASK_COMM_PAR_MXN_1D_BLOCK typed task."
872 "Cannot use this function.", task->name.c_str());
873 xbt_free(task->bytes_amount);
874 task->bytes_amount = xbt_new0(double,task->allocation->size() * task->allocation->size());
876 for (int i=0; i<src_nb; i++) {
877 double src_start = i*task->amount/src_nb;
878 double src_end = src_start + task->amount/src_nb;
879 for (int j=0; j<dst_nb; j++) {
880 double dst_start = j*task->amount/dst_nb;
881 double dst_end = dst_start + task->amount/dst_nb;
882 XBT_VERB("(%d->%d): (%.2f, %.2f)-> (%.2f, %.2f)", i, j, src_start, src_end, dst_start, dst_end);
883 task->bytes_amount[i*(src_nb+dst_nb)+src_nb+j]=0.0;
884 if ((src_end > dst_start) && (dst_end > src_start)) { /* There is something to send */
885 task->bytes_amount[i*(src_nb+dst_nb)+src_nb+j] = MIN(src_end, dst_end)- MAX(src_start, dst_start);
886 XBT_VERB("==> %.2f", task->bytes_amount[i*(src_nb+dst_nb)+src_nb+j]);
892 /** @brief Auto-schedules a task.
894 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
895 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
898 * To be auto-schedulable, a task must be a typed computation SD_TASK_COMP_SEQ or SD_TASK_COMP_PAR_AMDAHL.
900 void SD_task_schedulev(SD_task_t task, int count, const sg_host_t * list)
902 xbt_assert(task->kind == SD_TASK_COMP_SEQ || task->kind == SD_TASK_COMP_PAR_AMDAHL,
903 "Task %s is not typed. Cannot automatically schedule it.", SD_task_get_name(task));
905 for(int i =0; i<count; i++)
906 task->allocation->push_back(list[i]);
908 XBT_VERB("Schedule computation task %s on %zu host(s)", task->name.c_str(), task->allocation->size());
910 if (task->kind == SD_TASK_COMP_SEQ) {
911 if (!task->flops_amount){ /*This task has failed and is rescheduled. Reset the flops_amount*/
912 task->flops_amount = xbt_new0(double, 1);
913 task->flops_amount[0] = task->amount;
915 XBT_VERB("It costs %.f flops", task->flops_amount[0]);
918 if (task->kind == SD_TASK_COMP_PAR_AMDAHL) {
919 SD_task_distribute_comp_amdahl(task, count);
920 XBT_VERB("%.f flops will be distributed following Amdahl's Law", task->flops_amount[0]);
923 SD_task_do_schedule(task);
925 /* Iterate over all inputs and outputs to say where I am located (and start them if runnable) */
926 for (auto input : *task->inputs){
927 int src_nb = input->allocation->size();
929 if (input->allocation->empty())
930 XBT_VERB("Sender side of '%s' not scheduled. Set receiver side to '%s''s allocation", input->name.c_str(), task->name.c_str());
932 for (int i=0; i<count;i++)
933 input->allocation->push_back(task->allocation->at(i));
935 if (input->allocation->size () > task->allocation->size()) {
936 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
937 SD_task_build_MxN_1D_block_matrix(input, src_nb, dst_nb);
939 SD_task_do_schedule(input);
940 XBT_VERB ("Auto-Schedule Communication task '%s'. Send %.f bytes from %d hosts to %d hosts.",
941 input->name.c_str(),input->amount, src_nb, dst_nb);
945 for (auto output : *task->outputs){
947 int dst_nb = output->allocation->size();
948 if (output->allocation->empty())
949 XBT_VERB("Receiver side of '%s' not scheduled. Set sender side to '%s''s allocation", output->name.c_str(), task->name.c_str());
951 for (int i=0; i<count;i++)
952 output->allocation->insert(output->allocation->begin()+i, task->allocation->at(i));
954 if (output->allocation->size () > task->allocation->size()) {
955 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
956 SD_task_build_MxN_1D_block_matrix(output, src_nb, dst_nb);
958 SD_task_do_schedule(output);
959 XBT_VERB ("Auto-Schedule Communication task %s. Send %.f bytes from %d hosts to %d hosts.",
960 output->name.c_str(), output->amount, src_nb, dst_nb);
965 /** @brief autoschedule a task on a list of hosts
967 * This function is similar to SD_task_schedulev(), but takes the list of hosts to schedule onto as separate parameters.
968 * It builds a proper vector of hosts and then call SD_task_schedulev()
970 void SD_task_schedulel(SD_task_t task, int count, ...)
973 sg_host_t *list = xbt_new(sg_host_t, count);
975 for (int i=0; i<count; i++)
976 list[i] = va_arg(ap, sg_host_t);
979 SD_task_schedulev(task, count, list);