1 /* Copyright (c) 2006-2019. 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"
12 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(sd_task, sd, "Logging specific to SimDag (task)");
14 /* Destroys the data memorized by SD_task_schedule. Task state must be SD_SCHEDULED or SD_RUNNABLE. */
15 static void __SD_task_destroy_scheduling_data(SD_task_t task)
17 if (task->state != SD_SCHEDULED && task->state != SD_RUNNABLE)
18 THROWF(arg_error, 0, "Task '%s' must be SD_SCHEDULED or SD_RUNNABLE", SD_task_get_name(task));
20 xbt_free(task->flops_amount);
21 xbt_free(task->bytes_amount);
22 task->bytes_amount = nullptr;
23 task->flops_amount = nullptr;
27 * @brief Creates a new task.
29 * @param name the name of the task (can be @c nullptr)
30 * @param data the user data you want to associate with the task (can be @c nullptr)
31 * @param amount amount of the task
32 * @return the new task
33 * @see SD_task_destroy()
35 SD_task_t SD_task_create(const char *name, void *data, double amount)
37 SD_task_t task = xbt_new0(s_SD_task_t, 1);
38 task->kind = SD_TASK_NOT_TYPED;
39 task->state= SD_NOT_SCHEDULED;
40 sd_global->initial_tasks->insert(task);
43 task->start_time = -1.0;
44 task->finish_time = -1.0;
45 task->surf_action = nullptr;
46 task->watch_points = 0;
48 task->inputs = new std::set<SD_task_t>();
49 task->outputs = new std::set<SD_task_t>();
50 task->predecessors = new std::set<SD_task_t>();
51 task->successors = new std::set<SD_task_t>();
54 task->name = xbt_strdup(name);
55 task->amount = amount;
56 task->allocation = new std::vector<sg_host_t>();
61 static inline SD_task_t SD_task_create_sized(const char *name, void *data, double amount, int count)
63 SD_task_t task = SD_task_create(name, data, amount);
64 task->bytes_amount = xbt_new0(double, count * count);
65 task->flops_amount = xbt_new0(double, count);
69 /** @brief create a end-to-end communication task that can then be auto-scheduled
71 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
72 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
75 * A end-to-end communication must be scheduled on 2 hosts, and the amount specified at creation is sent from hosts[0]
78 SD_task_t SD_task_create_comm_e2e(const char *name, void *data, double amount)
80 SD_task_t res = SD_task_create_sized(name, data, amount, 2);
81 res->bytes_amount[2] = amount;
82 res->kind = SD_TASK_COMM_E2E;
87 /** @brief create a sequential computation task that can then be auto-scheduled
89 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
90 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
93 * A sequential computation must be scheduled on 1 host, and the amount specified at creation to be run on hosts[0].
95 * @param name the name of the task (can be @c nullptr)
96 * @param data the user data you want to associate with the task (can be @c nullptr)
97 * @param flops_amount amount of compute work to be done by the task
98 * @return the new SD_TASK_COMP_SEQ typed task
100 SD_task_t SD_task_create_comp_seq(const char *name, void *data, double flops_amount)
102 SD_task_t res = SD_task_create_sized(name, data, flops_amount, 1);
103 res->flops_amount[0] = flops_amount;
104 res->kind = SD_TASK_COMP_SEQ;
109 /** @brief create a parallel computation task that can then be auto-scheduled
111 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
112 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
115 * A parallel computation can be scheduled on any number of host.
116 * The underlying speedup model is Amdahl's law.
117 * To be auto-scheduled, @see SD_task_distribute_comp_amdahl has to be called first.
118 * @param name the name of the task (can be @c nullptr)
119 * @param data the user data you want to associate with the task (can be @c nullptr)
120 * @param flops_amount amount of compute work to be done by the task
121 * @param alpha purely serial fraction of the work to be done (in [0.;1.[)
122 * @return the new task
124 SD_task_t SD_task_create_comp_par_amdahl(const char *name, void *data, double flops_amount, double alpha)
126 xbt_assert(alpha < 1. && alpha >= 0., "Invalid parameter: alpha must be in [0.;1.[");
128 SD_task_t res = SD_task_create(name, data, flops_amount);
130 res->kind = SD_TASK_COMP_PAR_AMDAHL;
135 /** @brief create a complex data redistribution task that can then be auto-scheduled
137 * Auto-scheduling mean that the task can be used with SD_task_schedulev().
138 * This allows to specify the task costs at creation, and decouple them from the scheduling process where you just
139 * specify which resource should communicate.
141 * A data redistribution can be scheduled on any number of host.
142 * The assumed distribution is a 1D block distribution. Each host owns the same share of the @see amount.
143 * To be auto-scheduled, @see SD_task_distribute_comm_mxn_1d_block has to be called first.
144 * @param name the name of the task (can be @c nullptr)
145 * @param data the user data you want to associate with the task (can be @c nullptr)
146 * @param amount amount of data to redistribute by the task
147 * @return the new task
149 SD_task_t SD_task_create_comm_par_mxn_1d_block(const char *name, void *data, double amount)
151 SD_task_t res = SD_task_create(name, data, amount);
152 res->kind = SD_TASK_COMM_PAR_MXN_1D_BLOCK;
158 * @brief Destroys a task.
160 * The user data (if any) should have been destroyed first.
162 * @param task the task you want to destroy
163 * @see SD_task_create()
165 void SD_task_destroy(SD_task_t task)
167 XBT_DEBUG("Destroying task %s...", SD_task_get_name(task));
169 /* First Remove all dependencies associated with the task. */
170 while (not task->predecessors->empty())
171 SD_task_dependency_remove(*(task->predecessors->begin()), task);
172 while (not task->inputs->empty())
173 SD_task_dependency_remove(*(task->inputs->begin()), task);
174 while (not task->successors->empty())
175 SD_task_dependency_remove(task, *(task->successors->begin()));
176 while (not task->outputs->empty())
177 SD_task_dependency_remove(task, *(task->outputs->begin()));
179 if (task->state == SD_SCHEDULED || task->state == SD_RUNNABLE)
180 __SD_task_destroy_scheduling_data(task);
182 xbt_free(task->name);
184 if (task->surf_action != nullptr)
185 task->surf_action->unref();
187 delete task->allocation;
188 xbt_free(task->bytes_amount);
189 xbt_free(task->flops_amount);
191 delete task->outputs;
192 delete task->predecessors;
193 delete task->successors;
196 XBT_DEBUG("Task destroyed.");
200 * @brief Returns the user data of a task
203 * @return the user data associated with this task (can be @c nullptr)
204 * @see SD_task_set_data()
206 void *SD_task_get_data(SD_task_t task)
212 * @brief Sets the user data of a task
214 * The new data can be @c nullptr. The old data should have been freed first, if it was not @c nullptr.
217 * @param data the new data you want to associate with this task
218 * @see SD_task_get_data()
220 void SD_task_set_data(SD_task_t task, void *data)
226 * @brief Sets the rate of a task
228 * This will change the network bandwidth a task can use. This rate cannot be dynamically changed. Once the task has
229 * started, this call is ineffective. This rate depends on both the nominal bandwidth on the route onto which the task
230 * is scheduled (@see SD_task_get_current_bandwidth) and the amount of data to transfer.
232 * To divide the nominal bandwidth by 2, the rate then has to be :
233 * rate = bandwidth/(2*amount)
235 * @param task a @see SD_TASK_COMM_E2E task (end-to-end communication)
236 * @param rate the new rate you want to associate with this task.
238 void SD_task_set_rate(SD_task_t task, double rate)
240 xbt_assert(task->kind == SD_TASK_COMM_E2E, "The rate can be modified for end-to-end communications only.");
241 if(task->state < SD_RUNNING) {
244 XBT_WARN("Task %p has started. Changing rate is ineffective.", task);
249 * @brief Returns the state of a task
252 * @return the current @ref e_SD_task_state_t "state" of this task:
253 * #SD_NOT_SCHEDULED, #SD_SCHEDULED, #SD_RUNNABLE, #SD_RUNNING, #SD_DONE or #SD_FAILED
254 * @see e_SD_task_state_t
256 e_SD_task_state_t SD_task_get_state(SD_task_t task)
261 /* Changes the state of a task. Updates the sd_global->watch_point_reached flag.
263 void SD_task_set_state(SD_task_t task, e_SD_task_state_t new_state)
265 std::set<SD_task_t>::iterator idx;
266 XBT_DEBUG("Set state of '%s' to %d", task->name, new_state);
267 if ((new_state == SD_NOT_SCHEDULED || new_state == SD_SCHEDULABLE) && task->state == SD_FAILED){
268 sd_global->completed_tasks->erase(task);
269 sd_global->initial_tasks->insert(task);
272 if (new_state == SD_SCHEDULED && task->state == SD_RUNNABLE){
273 sd_global->initial_tasks->insert(task);
274 sd_global->runnable_tasks->erase(task);
277 if (new_state == SD_RUNNABLE){
278 idx = sd_global->initial_tasks->find(task);
279 if (idx != sd_global->initial_tasks->end()) {
280 sd_global->runnable_tasks->insert(*idx);
281 sd_global->initial_tasks->erase(idx);
285 if (new_state == SD_RUNNING)
286 sd_global->runnable_tasks->erase(task);
288 if (new_state == SD_DONE || new_state == SD_FAILED){
289 sd_global->completed_tasks->insert(task);
290 task->start_time = task->surf_action->get_start_time();
291 if (new_state == SD_DONE){
292 task->finish_time = task->surf_action->get_finish_time();
293 #if SIMGRID_HAVE_JEDULE
294 jedule_log_sd_event(task);
297 task->finish_time = surf_get_clock();
298 task->surf_action->unref();
299 task->surf_action = nullptr;
300 task->allocation->clear();
303 task->state = new_state;
305 if (task->watch_points & new_state) {
306 XBT_VERB("Watch point reached with task '%s'!", task->name);
307 sd_global->watch_point_reached = true;
308 SD_task_unwatch(task, new_state); /* remove the watch point */
313 * @brief Returns the name of a task
316 * @return the name of this task (can be @c nullptr)
318 const char *SD_task_get_name(SD_task_t task)
323 /** @brief Allows to change the name of a task */
324 void SD_task_set_name(SD_task_t task, const char *name)
326 xbt_free(task->name);
327 task->name = xbt_strdup(name);
330 /** @brief Returns the dynar of the parents of a task
333 * @return a newly allocated dynar comprising the parents of this task
336 xbt_dynar_t SD_task_get_parents(SD_task_t task)
338 xbt_dynar_t parents = xbt_dynar_new(sizeof(SD_task_t), nullptr);
340 for (auto const& it : *task->predecessors)
341 xbt_dynar_push(parents, &it);
342 for (auto const& it : *task->inputs)
343 xbt_dynar_push(parents, &it);
348 /** @brief Returns the dynar of the parents of a task
351 * @return a newly allocated dynar comprising the parents of this task
353 xbt_dynar_t SD_task_get_children(SD_task_t task)
355 xbt_dynar_t children = xbt_dynar_new(sizeof(SD_task_t), nullptr);
357 for (auto const& it : *task->successors)
358 xbt_dynar_push(children, &it);
359 for (auto const& it : *task->outputs)
360 xbt_dynar_push(children, &it);
366 * @brief Returns the number of workstations involved in a task
368 * Only call this on already scheduled tasks!
371 int SD_task_get_workstation_count(SD_task_t task)
373 return task->allocation->size();
377 * @brief Returns the list of workstations involved in a task
379 * Only call this on already scheduled tasks!
382 sg_host_t *SD_task_get_workstation_list(SD_task_t task)
384 return task->allocation->data();
388 * @brief Returns the total amount of work contained in a task
391 * @return the total amount of work (computation or data transfer) for this task
392 * @see SD_task_get_remaining_amount()
394 double SD_task_get_amount(SD_task_t task)
399 /** @brief Sets the total amount of work of a task
400 * For sequential typed tasks (COMP_SEQ and COMM_E2E), it also sets the appropriate values in the flops_amount and
401 * bytes_amount arrays respectively. Nothing more than modifying task->amount is done for parallel typed tasks
402 * (COMP_PAR_AMDAHL and COMM_PAR_MXN_1D_BLOCK) as the distribution of the amount of work is done at scheduling time.
405 * @param amount the new amount of work to execute
407 void SD_task_set_amount(SD_task_t task, double amount)
409 task->amount = amount;
410 if (task->kind == SD_TASK_COMP_SEQ)
411 task->flops_amount[0] = amount;
412 if (task->kind == SD_TASK_COMM_E2E)
413 task->bytes_amount[2] = amount;
417 * @brief Returns the alpha parameter of a SD_TASK_COMP_PAR_AMDAHL task
419 * @param task a parallel task assuming Amdahl's law as speedup model
420 * @return the alpha parameter (serial part of a task in percent) for this task
422 double SD_task_get_alpha(SD_task_t task)
424 xbt_assert(SD_task_get_kind(task) == SD_TASK_COMP_PAR_AMDAHL, "Alpha parameter is not defined for this kind of task");
429 * @brief Returns the remaining amount work to do till the completion of a task
432 * @return the remaining amount of work (computation or data transfer) of this task
433 * @see SD_task_get_amount()
435 double SD_task_get_remaining_amount(SD_task_t task)
437 if (task->surf_action)
438 return task->surf_action->get_remains();
440 return (task->state == SD_DONE) ? 0 : task->amount;
443 e_SD_task_kind_t SD_task_get_kind(SD_task_t task)
448 /** @brief Displays debugging information about a task */
449 void SD_task_dump(SD_task_t task)
451 XBT_INFO("Displaying task %s", SD_task_get_name(task));
452 if (task->state == SD_RUNNABLE)
453 XBT_INFO(" - state: runnable");
454 else if (task->state < SD_RUNNABLE)
455 XBT_INFO(" - state: %s not runnable", __get_state_name(task->state));
457 XBT_INFO(" - state: not runnable %s", __get_state_name(task->state));
459 if (task->kind != 0) {
460 switch (task->kind) {
461 case SD_TASK_COMM_E2E:
462 XBT_INFO(" - kind: end-to-end communication");
464 case SD_TASK_COMP_SEQ:
465 XBT_INFO(" - kind: sequential computation");
467 case SD_TASK_COMP_PAR_AMDAHL:
468 XBT_INFO(" - kind: parallel computation following Amdahl's law");
470 case SD_TASK_COMM_PAR_MXN_1D_BLOCK:
471 XBT_INFO(" - kind: MxN data redistribution assuming 1D block distribution");
474 XBT_INFO(" - (unknown kind %d)", task->kind);
478 XBT_INFO(" - amount: %.0f", SD_task_get_amount(task));
479 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
480 XBT_INFO(" - alpha: %.2f", task->alpha);
481 XBT_INFO(" - Dependencies to satisfy: %zu", task->inputs->size()+ task->predecessors->size());
482 if ((task->inputs->size()+ task->predecessors->size()) > 0) {
483 XBT_INFO(" - pre-dependencies:");
484 for (auto const& it : *task->predecessors)
485 XBT_INFO(" %s", it->name);
487 for (auto const& it : *task->inputs)
488 XBT_INFO(" %s", it->name);
490 if ((task->outputs->size() + task->successors->size()) > 0) {
491 XBT_INFO(" - post-dependencies:");
493 for (auto const& it : *task->successors)
494 XBT_INFO(" %s", it->name);
495 for (auto const& it : *task->outputs)
496 XBT_INFO(" %s", it->name);
500 /** @brief Dumps the task in dotty formalism into the FILE* passed as second argument */
501 void SD_task_dotty(SD_task_t task, void *out)
503 FILE *fout = static_cast<FILE*>(out);
504 fprintf(fout, " T%p [label=\"%.20s\"", task, task->name);
505 switch (task->kind) {
506 case SD_TASK_COMM_E2E:
507 case SD_TASK_COMM_PAR_MXN_1D_BLOCK:
508 fprintf(fout, ", shape=box");
510 case SD_TASK_COMP_SEQ:
511 case SD_TASK_COMP_PAR_AMDAHL:
512 fprintf(fout, ", shape=circle");
515 xbt_die("Unknown task type!");
517 fprintf(fout, "];\n");
518 for (auto const& it : *task->predecessors)
519 fprintf(fout, " T%p -> T%p;\n", it, task);
520 for (auto const& it : *task->inputs)
521 fprintf(fout, " T%p -> T%p;\n", it, task);
525 * @brief Adds a dependency between two tasks
527 * @a dst will depend on @a src, ie @a dst will not start before @a src is finished.
528 * Their @ref e_SD_task_state_t "state" must be #SD_NOT_SCHEDULED, #SD_SCHEDULED or #SD_RUNNABLE.
530 * @param src the task which must be executed first
531 * @param dst the task you want to make depend on @a src
532 * @see SD_task_dependency_remove()
534 void SD_task_dependency_add(SD_task_t src, SD_task_t dst)
537 THROWF(arg_error, 0, "Cannot add a dependency between task '%s' and itself", SD_task_get_name(src));
539 if (src->state == SD_DONE || src->state == SD_FAILED)
540 THROWF(arg_error, 0, "Task '%s' must be SD_NOT_SCHEDULED, SD_SCHEDULABLE, SD_SCHEDULED, SD_RUNNABLE, or SD_RUNNING",
543 if (dst->state == SD_DONE || dst->state == SD_FAILED || dst->state == SD_RUNNING)
544 THROWF(arg_error, 0, "Task '%s' must be SD_NOT_SCHEDULED, SD_SCHEDULABLE, SD_SCHEDULED, or SD_RUNNABLE",
547 if (dst->inputs->find(src) != dst->inputs->end() || src->outputs->find(dst) != src->outputs->end() ||
548 src->successors->find(dst) != src->successors->end() || dst->predecessors->find(src) != dst->predecessors->end())
549 THROWF(arg_error, 0, "A dependency already exists between task '%s' and task '%s'", src->name, dst->name);
551 XBT_DEBUG("SD_task_dependency_add: src = %s, dst = %s", src->name, dst->name);
553 if (src->kind == SD_TASK_COMM_E2E || src->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK){
554 if (dst->kind == SD_TASK_COMP_SEQ || dst->kind == SD_TASK_COMP_PAR_AMDAHL)
555 dst->inputs->insert(src);
557 dst->predecessors->insert(src);
558 src->successors->insert(dst);
560 if (dst->kind == SD_TASK_COMM_E2E|| dst->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK)
561 src->outputs->insert(dst);
563 src->successors->insert(dst);
564 dst->predecessors->insert(src);
567 /* if the task was runnable, the task goes back to SD_SCHEDULED because of the new dependency*/
568 if (dst->state == SD_RUNNABLE) {
569 XBT_DEBUG("SD_task_dependency_add: %s was runnable and becomes scheduled!", dst->name);
570 SD_task_set_state(dst, SD_SCHEDULED);
575 * @brief Indicates whether there is a dependency between two tasks.
578 * @param dst a task depending on @a src
580 * If src is nullptr, checks whether dst has any pre-dependency.
581 * If dst is nullptr, checks whether src has any post-dependency.
583 int SD_task_dependency_exists(SD_task_t src, SD_task_t dst)
585 xbt_assert(src != nullptr || dst != nullptr, "Invalid parameter: both src and dst are nullptr");
589 return (src->successors->find(dst) != src->successors->end() || src->outputs->find(dst) != src->outputs->end());
591 return src->successors->size() + src->outputs->size();
594 return dst->predecessors->size() + dst->inputs->size();
599 * @brief Remove a dependency between two tasks
602 * @param dst a task depending on @a src
603 * @see SD_task_dependency_add()
605 void SD_task_dependency_remove(SD_task_t src, SD_task_t dst)
607 XBT_DEBUG("SD_task_dependency_remove: src = %s, dst = %s", SD_task_get_name(src), SD_task_get_name(dst));
609 if (src->successors->find(dst) == src->successors->end() && src->outputs->find(dst) == src->outputs->end())
610 THROWF(arg_error, 0, "No dependency found between task '%s' and '%s': task '%s' is not a successor of task '%s'",
611 src->name, dst->name, dst->name, src->name);
613 if (src->kind == SD_TASK_COMM_E2E || src->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK){
614 if (dst->kind == SD_TASK_COMP_SEQ || dst->kind == SD_TASK_COMP_PAR_AMDAHL)
615 dst->inputs->erase(src);
617 dst->predecessors->erase(src);
618 src->successors->erase(dst);
620 if (dst->kind == SD_TASK_COMM_E2E|| dst->kind == SD_TASK_COMM_PAR_MXN_1D_BLOCK)
621 src->outputs->erase(dst);
623 src->successors->erase(dst);
624 dst->predecessors->erase(src);
627 /* if the task was scheduled and dependencies are satisfied, we can make it runnable */
628 if (dst->predecessors->empty() && dst->inputs->empty() && dst->state == SD_SCHEDULED)
629 SD_task_set_state(dst, SD_RUNNABLE);
633 * @brief Adds a watch point to a task
635 * SD_simulate() will stop as soon as the @ref e_SD_task_state_t "state" of this task becomes the one given in argument.
636 * The watch point is then automatically removed.
639 * @param state the @ref e_SD_task_state_t "state" you want to watch (cannot be #SD_NOT_SCHEDULED)
640 * @see SD_task_unwatch()
642 void SD_task_watch(SD_task_t task, e_SD_task_state_t state)
644 if (state & SD_NOT_SCHEDULED)
645 THROWF(arg_error, 0, "Cannot add a watch point for state SD_NOT_SCHEDULED");
647 task->watch_points = task->watch_points | state;
651 * @brief Removes a watch point from a task
654 * @param state the @ref e_SD_task_state_t "state" you no longer want to watch
655 * @see SD_task_watch()
657 void SD_task_unwatch(SD_task_t task, e_SD_task_state_t state)
659 xbt_assert(state != SD_NOT_SCHEDULED, "SimDag error: Cannot have a watch point for state SD_NOT_SCHEDULED");
660 task->watch_points = task->watch_points & ~state;
664 * @brief Returns an approximative estimation of the execution time of a task.
666 * The estimation is very approximative because the value returned is the time the task would take if it was executed
667 * now and if it was the only task.
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]->get_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 += (sg_host_route_latency(host_list[i], host_list[j]) +
691 bytes_amount[i * host_count + j] / sg_host_route_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 host_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);
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, (int) task->state);
792 xbt_assert(task->allocation != nullptr, "Task '%s': host_list is nullptr!", task->name);
794 XBT_VERB("Executing task '%s'", task->name);
796 /* Beware! The scheduling data are now used by the surf action directly! no copy was done */
798 surf_host_model->execute_parallel(*task->allocation, task->flops_amount, task->bytes_amount, task->rate);
800 task->surf_action->set_data(task);
802 XBT_DEBUG("surf_action = %p", task->surf_action);
804 SD_task_set_state(task, SD_RUNNING);
805 sd_global->return_set->insert(task);
809 * @brief Returns the start time of a task
811 * The task state must be SD_RUNNING, SD_DONE or SD_FAILED.
813 * @param task: a task
814 * @return the start time of this task
816 double SD_task_get_start_time(SD_task_t task)
818 if (task->surf_action)
819 return task->surf_action->get_start_time();
821 return task->start_time;
825 * @brief Returns the finish time of a task
827 * The task state must be SD_RUNNING, SD_DONE or SD_FAILED.
828 * If the state is not completed yet, the returned value is an estimation of the task finish time. This value can
829 * vary until the task is completed.
831 * @param task: a task
832 * @return the start time of this task
834 double SD_task_get_finish_time(SD_task_t task)
836 if (task->surf_action) /* should never happen as actions are destroyed right after their completion */
837 return task->surf_action->get_finish_time();
839 return task->finish_time;
842 void SD_task_distribute_comp_amdahl(SD_task_t task, int count)
844 xbt_assert(task->kind == SD_TASK_COMP_PAR_AMDAHL, "Task %s is not a SD_TASK_COMP_PAR_AMDAHL typed task."
845 "Cannot use this function.", task->name);
846 task->flops_amount = xbt_new0(double, count);
847 task->bytes_amount = xbt_new0(double, count * count);
849 for (int i=0; i<count; i++){
850 task->flops_amount[i] = (task->alpha + (1 - task->alpha)/count) * task->amount;
854 void SD_task_build_MxN_1D_block_matrix(SD_task_t task, int src_nb, int dst_nb){
855 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."
856 "Cannot use this function.", task->name);
857 xbt_free(task->bytes_amount);
858 task->bytes_amount = xbt_new0(double,task->allocation->size() * task->allocation->size());
860 for (int i=0; i<src_nb; i++) {
861 double src_start = i*task->amount/src_nb;
862 double src_end = src_start + task->amount/src_nb;
863 for (int j=0; j<dst_nb; j++) {
864 double dst_start = j*task->amount/dst_nb;
865 double dst_end = dst_start + task->amount/dst_nb;
866 XBT_VERB("(%d->%d): (%.2f, %.2f)-> (%.2f, %.2f)", i, j, src_start, src_end, dst_start, dst_end);
867 task->bytes_amount[i*(src_nb+dst_nb)+src_nb+j]=0.0;
868 if ((src_end > dst_start) && (dst_end > src_start)) { /* There is something to send */
869 task->bytes_amount[i * (src_nb + dst_nb) + src_nb + j] =
870 std::min(src_end, dst_end) - std::max(src_start, dst_start);
871 XBT_VERB("==> %.2f", task->bytes_amount[i*(src_nb+dst_nb)+src_nb+j]);
877 /** @brief Auto-schedules a task.
879 * Auto-scheduling mean that the task can be used with SD_task_schedulev(). This allows to specify the task costs at
880 * creation, and decouple them from the scheduling process where you just specify which resource should deliver the
883 * To be auto-schedulable, a task must be a typed computation SD_TASK_COMP_SEQ or SD_TASK_COMP_PAR_AMDAHL.
885 void SD_task_schedulev(SD_task_t task, int count, const sg_host_t * list)
887 xbt_assert(task->kind == SD_TASK_COMP_SEQ || task->kind == SD_TASK_COMP_PAR_AMDAHL,
888 "Task %s is not typed. Cannot automatically schedule it.", SD_task_get_name(task));
890 for(int i =0; i<count; i++)
891 task->allocation->push_back(list[i]);
893 XBT_VERB("Schedule computation task %s on %zu host(s)", task->name, task->allocation->size());
895 if (task->kind == SD_TASK_COMP_SEQ) {
896 if (not task->flops_amount) { /*This task has failed and is rescheduled. Reset the flops_amount*/
897 task->flops_amount = xbt_new0(double, 1);
898 task->flops_amount[0] = task->amount;
900 XBT_VERB("It costs %.f flops", task->flops_amount[0]);
903 if (task->kind == SD_TASK_COMP_PAR_AMDAHL) {
904 SD_task_distribute_comp_amdahl(task, count);
905 XBT_VERB("%.f flops will be distributed following Amdahl's Law", task->flops_amount[0]);
908 SD_task_do_schedule(task);
910 /* Iterate over all inputs and outputs to say where I am located (and start them if runnable) */
911 for (auto const& input : *task->inputs) {
912 int src_nb = input->allocation->size();
914 if (input->allocation->empty())
915 XBT_VERB("Sender side of '%s' not scheduled. Set receiver side to '%s''s allocation", input->name, task->name);
917 for (int i=0; i<count;i++)
918 input->allocation->push_back(task->allocation->at(i));
920 if (input->allocation->size () > task->allocation->size()) {
921 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
922 SD_task_build_MxN_1D_block_matrix(input, src_nb, dst_nb);
924 SD_task_do_schedule(input);
925 XBT_VERB ("Auto-Schedule Communication task '%s'. Send %.f bytes from %d hosts to %d hosts.",
926 input->name,input->amount, src_nb, dst_nb);
930 for (auto const& output : *task->outputs) {
932 int dst_nb = output->allocation->size();
933 if (output->allocation->empty())
934 XBT_VERB("Receiver side of '%s' not scheduled. Set sender side to '%s''s allocation", output->name, task->name);
936 for (int i=0; i<count;i++)
937 output->allocation->insert(output->allocation->begin()+i, task->allocation->at(i));
939 if (output->allocation->size () > task->allocation->size()) {
940 if (task->kind == SD_TASK_COMP_PAR_AMDAHL)
941 SD_task_build_MxN_1D_block_matrix(output, src_nb, dst_nb);
943 SD_task_do_schedule(output);
944 XBT_VERB ("Auto-Schedule Communication task %s. Send %.f bytes from %d hosts to %d hosts.",
945 output->name, output->amount, src_nb, dst_nb);
950 /** @brief autoschedule a task on a list of hosts
952 * This function is similar to SD_task_schedulev(), but takes the list of hosts to schedule onto as separate parameters.
953 * It builds a proper vector of hosts and then call SD_task_schedulev()
955 void SD_task_schedulel(SD_task_t task, int count, ...)
958 sg_host_t* list = new sg_host_t[count];
960 for (int i=0; i<count; i++)
961 list[i] = va_arg(ap, sg_host_t);
964 SD_task_schedulev(task, count, list);