1 /* Copyright (c) 2004-2017. The SimGrid Team. All rights reserved. */
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. */
6 /* \file callbacks.h */
8 #include "maxmin_private.hpp"
10 #include "xbt/mallocator.h"
11 #include "xbt/sysdep.h"
19 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_maxmin, surf, "Logging specific to SURF (maxmin)");
21 typedef std::vector<int> dyn_light_t;
23 double sg_maxmin_precision = 0.00001; /* Change this with --cfg=maxmin/precision:VALUE */
24 double sg_surf_precision = 0.00001; /* Change this with --cfg=surf/precision:VALUE */
25 int sg_concurrency_limit = -1; /* Change this with --cfg=maxmin/concurrency-limit:VALUE */
27 static void *lmm_variable_mallocator_new_f();
28 static void lmm_variable_mallocator_free_f(void *var);
29 #define lmm_variable_mallocator_reset_f ((void_f_pvoid_t)nullptr)
30 static void lmm_update_modified_set(lmm_system_t sys, lmm_constraint_t cnst);
31 static void lmm_remove_all_modified_set(lmm_system_t sys);
32 static int Global_debug_id = 1;
33 static int Global_const_debug_id = 1;
35 static inline void lmm_cnst_free(lmm_system_t sys, lmm_constraint_t cnst);
37 static void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr);
38 static void lmm_enable_var(lmm_system_t sys, lmm_variable_t var);
39 static int lmm_can_enable_var(lmm_variable_t var);
40 static void lmm_disable_var(lmm_system_t sys, lmm_variable_t var);
41 static int lmm_concurrency_slack(lmm_constraint_t cnstr);
42 static int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var);
44 inline int lmm_element_concurrency(lmm_element_t elem) {
45 //Ignore element with weight less than one (e.g. cross-traffic)
46 return (elem->consumption_weight >= 1) ? 1 : 0;
47 //There are other alternatives, but they will change the behaviour of the model..
48 //So do not use it unless you want to make a new model.
49 //If you do, remember to change the variables concurrency share to reflect it.
50 //Potential examples are:
51 //return (elem->weight>0)?1:0;//Include element as soon as weight is non-zero
52 //return (int)ceil(elem->weight);//Include element as the rounded-up integer value of the element weight
55 inline void lmm_decrease_concurrency(lmm_element_t elem) {
56 xbt_assert(elem->constraint->concurrency_current>=lmm_element_concurrency(elem));
57 elem->constraint->concurrency_current-=lmm_element_concurrency(elem);
60 inline void lmm_increase_concurrency(lmm_element_t elem) {
61 elem->constraint->concurrency_current+= lmm_element_concurrency(elem);
63 lmm_constraint_t cnstr=elem->constraint;
65 if(cnstr->concurrency_current > cnstr->concurrency_maximum)
66 cnstr->concurrency_maximum= cnstr->concurrency_current;
68 xbt_assert(cnstr->concurrency_limit<0 || cnstr->concurrency_current<=cnstr->concurrency_limit,
69 "Concurrency limit overflow!");
72 static void lmm_check_concurrency(lmm_system_t sys)
74 // These checks are very expensive, so do them only if we want to debug SURF LMM
75 if (not XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug))
79 xbt_swag_foreach(cnstIt, &(sys->constraint_set))
81 lmm_constraint_t cnst = (lmm_constraint_t)cnstIt;
84 xbt_swag_foreach(elemIt, &(cnst->enabled_element_set))
86 lmm_element_t elem = (lmm_element_t)elemIt;
87 xbt_assert(elem->variable->sharing_weight > 0);
88 concurrency += lmm_element_concurrency(elem);
91 xbt_swag_foreach(elemIt, &(cnst->disabled_element_set))
93 lmm_element_t elem = (lmm_element_t)elemIt;
94 // We should have staged variables only if concurrency is reached in some constraint
95 xbt_assert(cnst->concurrency_limit < 0 || elem->variable->staged_weight == 0 ||
96 lmm_cnstrs_min_concurrency_slack(elem->variable) < elem->variable->concurrency_share,
97 "should not have staged variable!");
100 xbt_assert(cnst->concurrency_limit < 0 || cnst->concurrency_limit >= concurrency, "concurrency check failed!");
101 xbt_assert(cnst->concurrency_current == concurrency, "concurrency_current is out-of-date!");
104 // Check that for each variable, all corresponding elements are in the same state (i.e. same element sets)
106 xbt_swag_foreach(varIt, &(sys->variable_set))
108 lmm_variable_t var = (lmm_variable_t)varIt;
110 if (var->cnsts.empty())
113 lmm_element_t elem = &var->cnsts[0];
114 int belong_to_enabled = xbt_swag_belongs(elem, &(elem->constraint->enabled_element_set));
115 int belong_to_disabled = xbt_swag_belongs(elem, &(elem->constraint->disabled_element_set));
116 int belong_to_active = xbt_swag_belongs(elem, &(elem->constraint->active_element_set));
118 for (s_lmm_element_t const& elem : var->cnsts) {
119 xbt_assert(belong_to_enabled == xbt_swag_belongs(&elem, &(elem.constraint->enabled_element_set)),
120 "Variable inconsistency (1): enabled_element_set");
121 xbt_assert(belong_to_disabled == xbt_swag_belongs(&elem, &(elem.constraint->disabled_element_set)),
122 "Variable inconsistency (2): disabled_element_set");
123 xbt_assert(belong_to_active == xbt_swag_belongs(&elem, &(elem.constraint->active_element_set)),
124 "Variable inconsistency (3): active_element_set");
129 static inline void lmm_variable_remove(lmm_system_t sys, lmm_variable_t var)
131 XBT_IN("(sys=%p, var=%p)", sys, var);
134 // TODOLATER Can do better than that by leaving only the variable in only one enabled_element_set, call
135 // lmm_update_modified_set, and then remove it..
136 if (not var->cnsts.empty())
137 lmm_update_modified_set(sys, var->cnsts[0].constraint);
139 for (s_lmm_element_t& elem : var->cnsts) {
140 if (var->sharing_weight > 0)
141 lmm_decrease_concurrency(&elem);
142 xbt_swag_remove(&elem, &(elem.constraint->enabled_element_set));
143 xbt_swag_remove(&elem, &(elem.constraint->disabled_element_set));
144 xbt_swag_remove(&elem, &(elem.constraint->active_element_set));
145 int nelements = xbt_swag_size(&(elem.constraint->enabled_element_set)) +
146 xbt_swag_size(&(elem.constraint->disabled_element_set));
148 make_constraint_inactive(sys, elem.constraint);
150 lmm_on_disabled_var(sys, elem.constraint);
153 // Check if we can enable new variables going through the constraints where var was.
154 // Do it after removing all elements, so the first disabled variables get priority over those with smaller requirement
155 for (s_lmm_element_t& elem : var->cnsts) {
156 if (xbt_swag_size(&(elem.constraint->disabled_element_set)))
157 lmm_on_disabled_var(sys, elem.constraint);
162 lmm_check_concurrency(sys);
167 static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
169 lmm_variable_remove(sys, var);
170 xbt_mallocator_release(sys->variable_mallocator, var);
173 lmm_system_t lmm_system_new(bool selective_update)
175 s_lmm_variable_t var;
176 s_lmm_constraint_t cnst;
178 lmm_system_t l = new s_lmm_system_t();
181 l->selective_update_active = selective_update;
182 l->visited_counter = 1;
184 XBT_DEBUG("Setting selective_update_active flag to %d", l->selective_update_active);
186 xbt_swag_init(&(l->variable_set), xbt_swag_offset(var, variable_set_hookup));
187 xbt_swag_init(&(l->constraint_set), xbt_swag_offset(cnst, constraint_set_hookup));
189 xbt_swag_init(&(l->active_constraint_set), xbt_swag_offset(cnst, active_constraint_set_hookup));
191 xbt_swag_init(&(l->modified_constraint_set), xbt_swag_offset(cnst, modified_constraint_set_hookup));
192 xbt_swag_init(&(l->saturated_variable_set), xbt_swag_offset(var, saturated_variable_set_hookup));
193 xbt_swag_init(&(l->saturated_constraint_set), xbt_swag_offset(cnst, saturated_constraint_set_hookup));
195 l->variable_mallocator = xbt_mallocator_new(65536,
196 lmm_variable_mallocator_new_f,
197 lmm_variable_mallocator_free_f,
198 lmm_variable_mallocator_reset_f);
200 l->solve_fun = &lmm_solve;
205 void lmm_system_free(lmm_system_t sys)
207 lmm_variable_t var = nullptr;
208 lmm_constraint_t cnst = nullptr;
213 while ((var = (lmm_variable_t) extract_variable(sys))) {
215 char* demangled = abi::__cxa_demangle(typeid(*var->id).name(), 0, 0, &status);
217 XBT_WARN("Probable bug: a %s variable (#%d) not removed before the LMM system destruction.", demangled,
220 lmm_var_free(sys, var);
222 while ((cnst = (lmm_constraint_t) extract_constraint(sys)))
223 lmm_cnst_free(sys, cnst);
225 xbt_mallocator_free(sys->variable_mallocator);
229 static inline void lmm_cnst_free(lmm_system_t sys, lmm_constraint_t cnst)
231 make_constraint_inactive(sys, cnst);
235 lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id, double bound_value)
237 lmm_constraint_t cnst = nullptr;
238 s_lmm_element_t elem;
240 cnst = new s_lmm_constraint_t();
242 cnst->id_int = Global_const_debug_id++;
243 xbt_swag_init(&(cnst->enabled_element_set), xbt_swag_offset(elem, enabled_element_set_hookup));
244 xbt_swag_init(&(cnst->disabled_element_set), xbt_swag_offset(elem, disabled_element_set_hookup));
245 xbt_swag_init(&(cnst->active_element_set), xbt_swag_offset(elem, active_element_set_hookup));
247 cnst->bound = bound_value;
248 cnst->concurrency_maximum=0;
249 cnst->concurrency_current=0;
250 cnst->concurrency_limit = sg_concurrency_limit;
252 cnst->sharing_policy = 1; /* FIXME: don't hardcode the value */
253 insert_constraint(sys, cnst);
258 int lmm_constraint_concurrency_limit_get(lmm_constraint_t cnst)
260 return cnst->concurrency_limit;
263 void lmm_constraint_concurrency_limit_set(lmm_constraint_t cnst, int concurrency_limit)
265 xbt_assert(concurrency_limit<0 || cnst->concurrency_maximum<=concurrency_limit,
266 "New concurrency limit should be larger than observed concurrency maximum. Maybe you want to call"
267 " lmm_constraint_concurrency_maximum_reset() to reset the maximum?");
268 cnst->concurrency_limit = concurrency_limit;
271 void lmm_constraint_concurrency_maximum_reset(lmm_constraint_t cnst)
273 cnst->concurrency_maximum = 0;
276 int lmm_constraint_concurrency_maximum_get(lmm_constraint_t cnst)
278 xbt_assert(cnst->concurrency_limit<0 || cnst->concurrency_maximum<=cnst->concurrency_limit,
279 "Very bad: maximum observed concurrency is higher than limit. This is a bug of SURF, please report it.");
280 return cnst->concurrency_maximum;
283 void lmm_constraint_shared(lmm_constraint_t cnst)
285 cnst->sharing_policy = 0;
288 /** Return true if the constraint is shared, and false if it's FATPIPE */
289 int lmm_constraint_sharing_policy(lmm_constraint_t cnst)
291 return (cnst->sharing_policy);
294 /* @brief Remove a constraint
295 * Currently this is dead code, but it is exposed in maxmin.hpp
296 * Apparently, this call was designed assuming that constraint would no more have elements in it.
297 * If not the case, assertion will fail, and you need to add calls e.g. to lmm_shrink before effectively removing it.
299 inline void lmm_constraint_free(lmm_system_t sys,lmm_constraint_t cnst)
301 xbt_assert(not xbt_swag_size(&(cnst->active_element_set)), "Removing constraint but it still has active elements");
302 xbt_assert(not xbt_swag_size(&(cnst->enabled_element_set)), "Removing constraint but it still has enabled elements");
303 xbt_assert(not xbt_swag_size(&(cnst->disabled_element_set)),
304 "Removing constraint but it still has disabled elements");
305 remove_constraint(sys, cnst);
306 lmm_cnst_free(sys, cnst);
309 static void *lmm_variable_mallocator_new_f()
311 return new s_lmm_variable_t;
314 static void lmm_variable_mallocator_free_f(void *var)
316 delete static_cast<lmm_variable_t>(var);
319 lmm_variable_t lmm_variable_new(lmm_system_t sys, simgrid::surf::Action* id, double sharing_weight, double bound,
320 int number_of_constraints)
322 XBT_IN("(sys=%p, id=%p, weight=%f, bound=%f, num_cons =%d)", sys, id, sharing_weight, bound, number_of_constraints);
324 lmm_variable_t var = (lmm_variable_t)xbt_mallocator_get(sys->variable_mallocator);
326 var->id_int = Global_debug_id++;
327 var->cnsts.reserve(number_of_constraints);
328 var->sharing_weight = sharing_weight;
329 var->staged_weight = 0.0;
331 var->concurrency_share = 1;
333 var->visited = sys->visited_counter - 1;
336 var->func_f = func_f_def;
337 var->func_fp = func_fp_def;
338 var->func_fpi = func_fpi_def;
340 var->variable_set_hookup.next = nullptr;
341 var->variable_set_hookup.prev = nullptr;
342 var->saturated_variable_set_hookup.next = nullptr;
343 var->saturated_variable_set_hookup.prev = nullptr;
346 xbt_swag_insert_at_head(var, &(sys->variable_set));
348 xbt_swag_insert_at_tail(var, &(sys->variable_set));
350 XBT_OUT(" returns %p", var);
354 void lmm_variable_free(lmm_system_t sys, lmm_variable_t var)
356 remove_variable(sys, var);
357 lmm_var_free(sys, var);
360 double lmm_variable_getvalue(lmm_variable_t var)
365 void lmm_variable_concurrency_share_set(lmm_variable_t var, short int concurrency_share)
367 var->concurrency_share=concurrency_share;
370 double lmm_variable_getbound(lmm_variable_t var)
375 void lmm_shrink(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var)
377 auto elem_it = std::find_if(begin(var->cnsts), end(var->cnsts),
378 [&cnst](s_lmm_element_t const& x) { return x.constraint == cnst; });
379 if (elem_it == end(var->cnsts)) {
380 XBT_DEBUG("cnst %p is not found in var %p", cnst, var);
383 s_lmm_element_t& elem = *elem_it;
387 XBT_DEBUG("remove elem(value %f, cnst %p, var %p) in var %p", elem.consumption_weight, elem.constraint, elem.variable,
390 /* We are going to change the constraint object and the variable object.
391 * Propagate this change to other objects. Calling here before removing variable from not active elements
392 * (inactive elements are not visited)
394 lmm_update_modified_set(sys, cnst);
395 //Useful in case var was already removed from the constraint
396 lmm_update_modified_set(sys, var->cnsts[0].constraint); // will look up enabled_element_set of this constraint, and
397 //then each var in the enabled_element_set, and each var->cnsts[i].
399 if (xbt_swag_remove(&elem, &(elem.constraint->enabled_element_set)))
400 lmm_decrease_concurrency(&elem);
402 xbt_swag_remove(&elem, &(elem.constraint->active_element_set));
403 elem.constraint = nullptr;
404 elem.variable = nullptr;
405 elem.consumption_weight = 0;
407 var->cnsts.pop_back();
409 //No variable in this constraint -> make it inactive
410 if (xbt_swag_size(&(cnst->enabled_element_set))+xbt_swag_size(&(cnst->disabled_element_set)) == 0)
411 make_constraint_inactive(sys, cnst);
413 //Check maxconcurrency to see if we can enable new variables
414 lmm_on_disabled_var(sys, elem.constraint);
417 lmm_check_concurrency(sys);
420 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double consumption_weight)
424 //Check if this variable already has an active element in this constraint
425 //If it does, substract it from the required slack
426 int current_share = 0;
427 if(var->concurrency_share>1){
428 for (s_lmm_element_t& elem : var->cnsts) {
429 if (elem.constraint == cnst && xbt_swag_belongs(&elem, &(elem.constraint->enabled_element_set)))
430 current_share += lmm_element_concurrency(&elem);
434 //Check if we need to disable the variable
435 if (var->sharing_weight > 0 && var->concurrency_share - current_share > lmm_concurrency_slack(cnst)) {
436 double weight = var->sharing_weight;
437 lmm_disable_var(sys,var);
438 for (s_lmm_element_t const& elem : var->cnsts)
439 lmm_on_disabled_var(sys, elem.constraint);
440 consumption_weight = 0;
441 var->staged_weight=weight;
442 xbt_assert(not var->sharing_weight);
445 xbt_assert(var->cnsts.size() < var->cnsts.capacity(), "Too much constraints");
447 var->cnsts.resize(var->cnsts.size() + 1);
448 s_lmm_element_t& elem = var->cnsts.back();
450 elem.consumption_weight = consumption_weight;
451 elem.constraint = cnst;
454 if (var->sharing_weight) {
455 xbt_swag_insert_at_head(&elem, &(elem.constraint->enabled_element_set));
456 lmm_increase_concurrency(&elem);
458 xbt_swag_insert_at_tail(&elem, &(elem.constraint->disabled_element_set));
460 if (not sys->selective_update_active) {
461 make_constraint_active(sys, cnst);
462 } else if (elem.consumption_weight > 0 || var->sharing_weight > 0) {
463 make_constraint_active(sys, cnst);
464 lmm_update_modified_set(sys, cnst);
465 //TODOLATER: Why do we need this second call?
466 if (var->cnsts.size() > 1)
467 lmm_update_modified_set(sys, var->cnsts[0].constraint);
470 lmm_check_concurrency(sys);
473 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double value)
477 lmm_check_concurrency(sys);
479 //BEWARE: In case you have multiple elements in one constraint, this will always add value to the first element.
480 auto elem_it = std::find_if(begin(var->cnsts), end(var->cnsts),
481 [&cnst](s_lmm_element_t const& x) { return x.constraint == cnst; });
482 if (elem_it != end(var->cnsts)) {
483 s_lmm_element_t& elem = *elem_it;
484 if (var->sharing_weight)
485 lmm_decrease_concurrency(&elem);
487 if (cnst->sharing_policy)
488 elem.consumption_weight += value;
490 elem.consumption_weight = MAX(elem.consumption_weight, value);
492 //We need to check that increasing value of the element does not cross the concurrency limit
493 if (var->sharing_weight) {
494 if (lmm_concurrency_slack(cnst) < lmm_element_concurrency(&elem)) {
495 double weight = var->sharing_weight;
496 lmm_disable_var(sys,var);
497 for (s_lmm_element_t const& elem2 : var->cnsts)
498 lmm_on_disabled_var(sys, elem2.constraint);
499 var->staged_weight=weight;
500 xbt_assert(not var->sharing_weight);
502 lmm_increase_concurrency(&elem);
504 lmm_update_modified_set(sys, cnst);
506 lmm_expand(sys, cnst, var, value);
508 lmm_check_concurrency(sys);
511 lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var, unsigned num)
513 if (num < var->cnsts.size())
514 return (var->cnsts[num].constraint);
519 double lmm_get_cnst_weight_from_var(lmm_system_t /*sys*/, lmm_variable_t var, unsigned num)
521 if (num < var->cnsts.size())
522 return (var->cnsts[num].consumption_weight);
527 int lmm_get_number_of_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var)
529 return (var->cnsts.size());
532 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem)
534 if (*elem == nullptr) {
535 // That is the first call, pick the first element among enabled_element_set (or disabled_element_set if
536 // enabled_element_set is empty)
537 *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
538 if (*elem == nullptr)
539 *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
541 //elem is not null, so we carry on
542 if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
543 //Look at enabled_element_set, and jump to disabled_element_set when finished
544 *elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
545 if (*elem == nullptr)
546 *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
548 *elem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
552 return (*elem)->variable;
557 //if we modify the swag between calls, normal version may loop forever
558 //this safe version ensures that we browse the swag elements only once
559 lmm_variable_t lmm_get_var_from_cnst_safe(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem,
560 lmm_element_t * nextelem, int * numelem)
562 if (*elem == nullptr) {
563 *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->enabled_element_set));
564 *numelem = xbt_swag_size(&(cnst->enabled_element_set))+xbt_swag_size(&(cnst->disabled_element_set))-1;
565 if (*elem == nullptr)
566 *elem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
575 //elem is not null, so we carry on
576 if(xbt_swag_belongs(*elem,&(cnst->enabled_element_set))){
577 //Look at enabled_element_set, and jump to disabled_element_set when finished
578 *nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->enabled_element_set.offset);
579 if (*nextelem == nullptr)
580 *nextelem = (lmm_element_t) xbt_swag_getFirst(&(cnst->disabled_element_set));
582 *nextelem = (lmm_element_t) xbt_swag_getNext(*elem, cnst->disabled_element_set.offset);
584 return (*elem)->variable;
589 void *lmm_constraint_id(lmm_constraint_t cnst)
594 void *lmm_variable_id(lmm_variable_t var)
599 static inline void saturated_constraint_set_update(double usage, int cnst_light_num,
600 dyn_light_t& saturated_constraint_set, double* min_usage)
602 xbt_assert(usage > 0,"Impossible");
604 if (*min_usage < 0 || *min_usage > usage) {
606 XBT_HERE(" min_usage=%f (cnst->remaining / cnst->usage =%f)", *min_usage, usage);
607 saturated_constraint_set.assign(1, cnst_light_num);
608 } else if (*min_usage == usage) {
609 saturated_constraint_set.emplace_back(cnst_light_num);
613 static inline void saturated_variable_set_update(s_lmm_constraint_light_t* cnst_light_tab,
614 const dyn_light_t& saturated_constraint_set, lmm_system_t sys)
616 /* Add active variables (i.e. variables that need to be set) from the set of constraints to saturate (cnst_light_tab)*/
617 for (int const& saturated_cnst : saturated_constraint_set) {
618 lmm_constraint_light_t cnst = &cnst_light_tab[saturated_cnst];
620 xbt_swag_t elem_list = &(cnst->cnst->active_element_set);
621 xbt_swag_foreach(_elem, elem_list) {
622 lmm_element_t elem = (lmm_element_t)_elem;
623 //Visiting active_element_set, so, by construction, should never get a zero weight, correct?
624 xbt_assert(elem->variable->sharing_weight > 0);
625 if (elem->consumption_weight > 0)
626 xbt_swag_insert(elem->variable, &(sys->saturated_variable_set));
631 void lmm_print(lmm_system_t sys)
633 std::string buf = std::string("MAX-MIN ( ");
636 /* Printing Objective */
637 xbt_swag_t var_list = &(sys->variable_set);
638 xbt_swag_foreach(_var, var_list) {
639 lmm_variable_t var = (lmm_variable_t)_var;
640 buf = buf + "'" + std::to_string(var->id_int) + "'(" + std::to_string(var->sharing_weight) + ") ";
643 XBT_DEBUG("%20s", buf.c_str());
646 XBT_DEBUG("Constraints");
647 /* Printing Constraints */
649 xbt_swag_t cnst_list = &(sys->active_constraint_set);
650 xbt_swag_foreach(_cnst, cnst_list) {
651 lmm_constraint_t cnst = (lmm_constraint_t)_cnst;
653 //Show the enabled variables
655 xbt_swag_t elem_list = &(cnst->enabled_element_set);
657 buf += ((cnst->sharing_policy) ? "(" : "max(");
658 xbt_swag_foreach(_elem, elem_list) {
659 lmm_element_t elem = (lmm_element_t)_elem;
660 buf = buf + std::to_string(elem->consumption_weight) + ".'" + std::to_string(elem->variable->id_int) + "'(" +
661 std::to_string(elem->variable->value) + ")" + ((cnst->sharing_policy) ? " + " : " , ");
662 if(cnst->sharing_policy)
663 sum += elem->consumption_weight * elem->variable->value;
665 sum = MAX(sum, elem->consumption_weight * elem->variable->value);
667 //TODO: Adding disabled elements only for test compatibility, but do we really want them to be printed?
668 elem_list = &(cnst->disabled_element_set);
669 xbt_swag_foreach(_elem, elem_list) {
670 lmm_element_t elem = (lmm_element_t)_elem;
671 buf = buf + std::to_string(elem->consumption_weight) + ".'" + std::to_string(elem->variable->id_int) + "'(" +
672 std::to_string(elem->variable->value) + ")" + ((cnst->sharing_policy) ? " + " : " , ");
673 if(cnst->sharing_policy)
674 sum += elem->consumption_weight * elem->variable->value;
676 sum = MAX(sum, elem->consumption_weight * elem->variable->value);
679 buf = buf + "0) <= " + std::to_string(cnst->bound) + " ('" + std::to_string(cnst->id_int) + "')";
681 if (not cnst->sharing_policy) {
682 buf += " [MAX-Constraint]";
684 XBT_DEBUG("%s", buf.c_str());
686 xbt_assert(not double_positive(sum - cnst->bound, cnst->bound * sg_maxmin_precision),
687 "Incorrect value (%f is not smaller than %f): %g", sum, cnst->bound, sum - cnst->bound);
690 XBT_DEBUG("Variables");
691 /* Printing Result */
692 xbt_swag_foreach(_var, var_list) {
693 lmm_variable_t var = (lmm_variable_t)_var;
694 if (var->bound > 0) {
695 XBT_DEBUG("'%d'(%f) : %f (<=%f)", var->id_int, var->sharing_weight, var->value, var->bound);
696 xbt_assert(not double_positive(var->value - var->bound, var->bound * sg_maxmin_precision),
697 "Incorrect value (%f is not smaller than %f", var->value, var->bound);
699 XBT_DEBUG("'%d'(%f) : %f", var->id_int, var->sharing_weight, var->value);
704 void lmm_solve(lmm_system_t sys)
709 double min_usage = -1;
710 double min_bound = -1;
712 if (not sys->modified)
715 XBT_IN("(sys=%p)", sys);
717 /* Compute Usage and store the variables that reach the maximum. If selective_update_active is true, only constraints
718 * that changed are considered. Otherwise all constraints with active actions are considered.
720 xbt_swag_t cnst_list = sys->selective_update_active ? &(sys->modified_constraint_set) : &(sys->active_constraint_set);
722 XBT_DEBUG("Active constraints : %d", xbt_swag_size(cnst_list));
723 /* Init: Only modified code portions: reset the value of active variables */
724 xbt_swag_foreach(_cnst, cnst_list) {
725 lmm_constraint_t cnst = (lmm_constraint_t)_cnst;
726 xbt_swag_t elem_list = &(cnst->enabled_element_set);
727 xbt_swag_foreach(_elem, elem_list) {
728 lmm_variable_t var = ((lmm_element_t)_elem)->variable;
729 xbt_assert(var->sharing_weight > 0.0);
734 s_lmm_constraint_light_t* cnst_light_tab = new s_lmm_constraint_light_t[xbt_swag_size(cnst_list)]();
735 int cnst_light_num = 0;
736 dyn_light_t saturated_constraint_set;
738 xbt_swag_foreach_safe(_cnst, _cnst_next, cnst_list) {
739 lmm_constraint_t cnst = (lmm_constraint_t)_cnst;
740 /* INIT: Collect constraints that actually need to be saturated (i.e remaining and usage are strictly positive)
741 * into cnst_light_tab. */
742 cnst->remaining = cnst->bound;
743 if (not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision))
746 xbt_swag_t elem_list = &(cnst->enabled_element_set);
747 xbt_swag_foreach(_elem, elem_list) {
748 lmm_element_t elem = (lmm_element_t)_elem;
749 xbt_assert(elem->variable->sharing_weight > 0);
750 if (elem->consumption_weight > 0) {
751 if (cnst->sharing_policy)
752 cnst->usage += elem->consumption_weight / elem->variable->sharing_weight;
753 else if (cnst->usage < elem->consumption_weight / elem->variable->sharing_weight)
754 cnst->usage = elem->consumption_weight / elem->variable->sharing_weight;
756 make_elem_active(elem);
757 simgrid::surf::Action *action = static_cast<simgrid::surf::Action*>(elem->variable->id);
758 if (sys->keep_track && not action->is_linked())
759 sys->keep_track->push_back(*action);
762 XBT_DEBUG("Constraint '%d' usage: %f remaining: %f concurrency: %i<=%i<=%i", cnst->id_int, cnst->usage,
763 cnst->remaining,cnst->concurrency_current,cnst->concurrency_maximum,cnst->concurrency_limit);
764 /* Saturated constraints update */
766 if(cnst->usage > 0) {
767 cnst_light_tab[cnst_light_num].cnst = cnst;
768 cnst->cnst_light = &(cnst_light_tab[cnst_light_num]);
769 cnst_light_tab[cnst_light_num].remaining_over_usage = cnst->remaining / cnst->usage;
770 saturated_constraint_set_update(cnst_light_tab[cnst_light_num].remaining_over_usage,
771 cnst_light_num, saturated_constraint_set, &min_usage);
772 xbt_assert(cnst->active_element_set.count>0, "There is no sense adding a constraint that has no active element!");
777 saturated_variable_set_update( cnst_light_tab, saturated_constraint_set, sys);
779 /* Saturated variables update */
781 /* Fix the variables that have to be */
782 xbt_swag_t var_list = &(sys->saturated_variable_set);
784 lmm_variable_t var = nullptr;
785 xbt_swag_foreach(_var, var_list) {
786 var = (lmm_variable_t)_var;
787 if (var->sharing_weight <= 0.0)
789 /* First check if some of these variables could reach their upper bound and update min_bound accordingly. */
790 XBT_DEBUG("var=%d, var->bound=%f, var->weight=%f, min_usage=%f, var->bound*var->weight=%f", var->id_int,
791 var->bound, var->sharing_weight, min_usage, var->bound * var->sharing_weight);
792 if ((var->bound > 0) && (var->bound * var->sharing_weight < min_usage)) {
794 min_bound = var->bound * var->sharing_weight;
796 min_bound = MIN(min_bound, (var->bound * var->sharing_weight));
797 XBT_DEBUG("Updated min_bound=%f", min_bound);
801 while ((var = (lmm_variable_t)xbt_swag_getFirst(var_list))) {
803 //If no variable could reach its bound, deal iteratively the constraints usage ( at worst one constraint is
804 // saturated at each cycle)
805 var->value = min_usage / var->sharing_weight;
806 XBT_DEBUG("Setting var (%d) value to %f\n", var->id_int, var->value);
808 //If there exist a variable that can reach its bound, only update it (and other with the same bound) for now.
809 if (double_equals(min_bound, var->bound * var->sharing_weight, sg_maxmin_precision)) {
810 var->value = var->bound;
811 XBT_DEBUG("Setting %p (%d) value to %f\n", var, var->id_int, var->value);
813 // Variables which bound is different are not considered for this cycle, but they will be afterwards.
814 XBT_DEBUG("Do not consider %p (%d) \n", var, var->id_int);
815 xbt_swag_remove(var, var_list);
819 XBT_DEBUG("Min usage: %f, Var(%d)->weight: %f, Var(%d)->value: %f ", min_usage, var->id_int, var->sharing_weight,
820 var->id_int, var->value);
822 /* Update the usage of contraints where this variable is involved */
823 for (s_lmm_element_t& elem : var->cnsts) {
824 lmm_constraint_t cnst = elem.constraint;
825 if (cnst->sharing_policy) {
826 // Remember: shared constraints require that sum(elem.value * var->value) < cnst->bound
827 double_update(&(cnst->remaining), elem.consumption_weight * var->value, cnst->bound * sg_maxmin_precision);
828 double_update(&(cnst->usage), elem.consumption_weight / var->sharing_weight, sg_maxmin_precision);
829 // If the constraint is saturated, remove it from the set of active constraints (light_tab)
830 if (not double_positive(cnst->usage, sg_maxmin_precision) ||
831 not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision)) {
832 if (cnst->cnst_light) {
833 int index = (cnst->cnst_light-cnst_light_tab);
834 XBT_DEBUG("index: %d \t cnst_light_num: %d \t || usage: %f remaining: %f bound: %f ",
835 index,cnst_light_num, cnst->usage, cnst->remaining, cnst->bound);
836 cnst_light_tab[index]=cnst_light_tab[cnst_light_num-1];
837 cnst_light_tab[index].cnst->cnst_light = &cnst_light_tab[index];
839 cnst->cnst_light = nullptr;
842 cnst->cnst_light->remaining_over_usage = cnst->remaining / cnst->usage;
844 make_elem_inactive(&elem);
846 // Remember: non-shared constraints only require that max(elem.value * var->value) < cnst->bound
848 make_elem_inactive(&elem);
849 xbt_swag_t elem_list = &(cnst->enabled_element_set);
850 xbt_swag_foreach(_elem, elem_list) {
851 lmm_element_t elem2 = static_cast<lmm_element_t>(_elem);
852 xbt_assert(elem2->variable->sharing_weight > 0);
853 if (elem2->variable->value > 0)
855 if (elem2->consumption_weight > 0)
856 cnst->usage = MAX(cnst->usage, elem2->consumption_weight / elem2->variable->sharing_weight);
858 //If the constraint is saturated, remove it from the set of active constraints (light_tab)
859 if (not double_positive(cnst->usage, sg_maxmin_precision) ||
860 not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision)) {
861 if(cnst->cnst_light) {
862 int index = (cnst->cnst_light-cnst_light_tab);
863 XBT_DEBUG("index: %d \t cnst_light_num: %d \t || \t cnst: %p \t cnst->cnst_light: %p "
864 "\t cnst_light_tab: %p usage: %f remaining: %f bound: %f ", index,cnst_light_num, cnst,
865 cnst->cnst_light, cnst_light_tab, cnst->usage, cnst->remaining, cnst->bound);
866 cnst_light_tab[index]=cnst_light_tab[cnst_light_num-1];
867 cnst_light_tab[index].cnst->cnst_light = &cnst_light_tab[index];
869 cnst->cnst_light = nullptr;
872 cnst->cnst_light->remaining_over_usage = cnst->remaining / cnst->usage;
873 xbt_assert(cnst->active_element_set.count>0, "Should not keep a maximum constraint that has no active"
874 " element! You want to check the maxmin precision and possible rounding effects." );
878 xbt_swag_remove(var, var_list);
881 /* Find out which variables reach the maximum */
884 saturated_constraint_set.clear();
886 for(pos=0; pos<cnst_light_num; pos++){
887 xbt_assert(cnst_light_tab[pos].cnst->active_element_set.count>0, "Cannot saturate more a constraint that has"
888 " no active element! You may want to change the maxmin precision (--cfg=maxmin/precision:<new_value>)"
889 " because of possible rounding effects.\n\tFor the record, the usage of this constraint is %g while "
890 "the maxmin precision to which it is compared is %g.\n\tThe usage of the previous constraint is %g.",
891 cnst_light_tab[pos].cnst->usage, sg_maxmin_precision, cnst_light_tab[pos-1].cnst->usage);
892 saturated_constraint_set_update(cnst_light_tab[pos].remaining_over_usage, pos, saturated_constraint_set,
896 saturated_variable_set_update(cnst_light_tab, saturated_constraint_set, sys);
898 } while (cnst_light_num > 0);
901 if (sys->selective_update_active)
902 lmm_remove_all_modified_set(sys);
904 if (XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug)) {
908 lmm_check_concurrency(sys);
910 delete[] cnst_light_tab;
914 /** \brief Attribute the value bound to var->bound.
916 * \param sys the lmm_system_t
917 * \param var the lmm_variable_t
918 * \param bound the new bound to associate with var
920 * Makes var->bound equal to bound. Whenever this function is called a change is signed in the system. To
921 * avoid false system changing detection it is a good idea to test (bound != 0) before calling it.
923 void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var, double bound)
928 if (not var->cnsts.empty())
929 lmm_update_modified_set(sys, var->cnsts[0].constraint);
932 int lmm_concurrency_slack(lmm_constraint_t cnstr){
933 //FIXME MARTIN: Replace by infinite value std::numeric_limits<int>::(max)(), or something better within Simgrid?
934 if(cnstr->concurrency_limit<0)
937 return cnstr->concurrency_limit - cnstr->concurrency_current;
940 /** \brief Measure the minimum concurrency slack across all constraints where the given var is involved */
941 int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var){
942 int minslack = std::numeric_limits<int>::max();
943 for (s_lmm_element_t const& elem : var->cnsts) {
944 int slack = lmm_concurrency_slack(elem.constraint);
946 //This is only an optimization, to avoid looking at more constraints when slack is already zero
947 //Disable it when debugging to let lmm_concurrency_slack catch nasty things
948 if (not slack && not XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug))
958 /* /Check if a variable can be enabled
960 * Make sure to set staged_weight before, if your intent is only to check concurrency
962 int lmm_can_enable_var(lmm_variable_t var){
963 return var->staged_weight>0 && lmm_cnstrs_min_concurrency_slack(var)>=var->concurrency_share;
966 //Small remark: In this implementation of lmm_enable_var and lmm_disable_var, we will meet multiple times with var when
967 // running lmm_update_modified_set.
968 //A priori not a big performance issue, but we might do better by calling lmm_update_modified_set within the for loops
969 // (after doing the first for enabling==1, and before doing the last for disabling==1)
970 void lmm_enable_var(lmm_system_t sys, lmm_variable_t var){
971 xbt_assert(lmm_can_enable_var(var));
973 var->sharing_weight = var->staged_weight;
974 var->staged_weight = 0;
976 // Enabling the variable, move to var to list head. Subtlety is: here, we need to call lmm_update_modified_set AFTER
977 // moving at least one element of var.
979 xbt_swag_remove(var, &(sys->variable_set));
980 xbt_swag_insert_at_head(var, &(sys->variable_set));
981 for (s_lmm_element_t& elem : var->cnsts) {
982 xbt_swag_remove(&elem, &(elem.constraint->disabled_element_set));
983 xbt_swag_insert_at_head(&elem, &(elem.constraint->enabled_element_set));
984 lmm_increase_concurrency(&elem);
986 if (not var->cnsts.empty())
987 lmm_update_modified_set(sys, var->cnsts[0].constraint);
989 //When used within lmm_on_disabled_var, we would get an assertion fail, because transiently there can be variables
990 // that are staged and could be activated.
991 //Anyway, caller functions all call lmm_check_concurrency() in the end.
994 void lmm_disable_var(lmm_system_t sys, lmm_variable_t var){
995 xbt_assert(not var->staged_weight, "Staged weight should have been cleared");
996 // Disabling the variable, move to var to list tail. Subtlety is: here, we need to call lmm_update_modified_set BEFORE
997 // moving the last element of var.
998 xbt_swag_remove(var, &(sys->variable_set));
999 xbt_swag_insert_at_tail(var, &(sys->variable_set));
1000 if (not var->cnsts.empty())
1001 lmm_update_modified_set(sys, var->cnsts[0].constraint);
1002 for (s_lmm_element_t& elem : var->cnsts) {
1003 xbt_swag_remove(&elem, &(elem.constraint->enabled_element_set));
1004 xbt_swag_insert_at_tail(&elem, &(elem.constraint->disabled_element_set));
1006 xbt_swag_remove(&elem, &(elem.constraint->active_element_set));
1008 lmm_decrease_concurrency(&elem);
1011 var->sharing_weight = 0.0;
1012 var->staged_weight=0.0;
1014 lmm_check_concurrency(sys);
1017 /* /brief Find variables that can be enabled and enable them.
1019 * Assuming that the variable has already been removed from non-zero weights
1020 * Can we find a staged variable to add?
1021 * If yes, check that none of the constraints that this variable is involved in is at the limit of its concurrency
1022 * And then add it to enabled variables
1024 void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
1026 if(cnstr->concurrency_limit<0)
1029 int numelem = xbt_swag_size(&(cnstr->disabled_element_set));
1033 lmm_element_t elem = (lmm_element_t)xbt_swag_getFirst(&(cnstr->disabled_element_set));
1035 //Cannot use xbt_swag_foreach, because lmm_enable_var will modify disabled_element_set.. within the loop
1036 while (numelem-- && elem) {
1038 lmm_element_t nextelem = (lmm_element_t)xbt_swag_getNext(elem, cnstr->disabled_element_set.offset);
1040 if (elem->variable->staged_weight>0 ){
1041 //Found a staged variable
1042 //TODOLATER: Add random timing function to model reservation protocol fuzziness? Then how to make sure that
1043 //staged variables will eventually be called?
1044 if(lmm_can_enable_var(elem->variable)){
1045 lmm_enable_var(sys,elem->variable);
1049 xbt_assert(cnstr->concurrency_current<=cnstr->concurrency_limit,"Concurrency overflow!");
1050 if(cnstr->concurrency_current==cnstr->concurrency_limit)
1056 //We could get an assertion fail, because transiently there can be variables that are staged and could be activated.
1057 //And we need to go through all constraints of the disabled var before getting back a coherent state.
1058 //Anyway, caller functions all call lmm_check_concurrency() in the end.
1061 /* \brief update the weight of a variable, and enable/disable it.
1062 * @return Returns whether a change was made
1064 void lmm_update_variable_weight(lmm_system_t sys, lmm_variable_t var, double weight)
1066 xbt_assert(weight>=0,"Variable weight should not be negative!");
1068 if (weight == var->sharing_weight)
1071 int enabling_var = (weight > 0 && var->sharing_weight <= 0);
1072 int disabling_var = (weight <= 0 && var->sharing_weight > 0);
1074 XBT_IN("(sys=%p, var=%p, weight=%f)", sys, var, weight);
1078 //Are we enabling this variable?
1080 var->staged_weight = weight;
1081 int minslack = lmm_cnstrs_min_concurrency_slack(var);
1082 if (minslack < var->concurrency_share) {
1083 XBT_DEBUG("Staging var (instead of enabling) because min concurrency slack %i, with weight %f and concurrency"
1084 " share %i", minslack, weight, var->concurrency_share);
1087 XBT_DEBUG("Enabling var with min concurrency slack %i", minslack);
1088 lmm_enable_var(sys,var);
1089 } else if (disabling_var){
1090 //Are we disabling this variable?
1091 lmm_disable_var(sys,var);
1093 var->sharing_weight = weight;
1096 lmm_check_concurrency(sys);
1101 double lmm_get_variable_weight(lmm_variable_t var)
1103 return var->sharing_weight;
1106 void lmm_update_constraint_bound(lmm_system_t sys, lmm_constraint_t cnst, double bound)
1109 lmm_update_modified_set(sys, cnst);
1110 cnst->bound = bound;
1113 int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
1115 return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
1118 inline lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t sys)
1120 return (lmm_constraint_t)xbt_swag_getFirst(&(sys->active_constraint_set));
1123 inline lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t sys, lmm_constraint_t cnst)
1125 return (lmm_constraint_t)xbt_swag_getNext(cnst, (sys->active_constraint_set).offset);
1128 /** \brief Update the constraint set propagating recursively to other constraints so the system should not be entirely
1131 * \param sys the lmm_system_t
1132 * \param cnst the lmm_constraint_t affected by the change
1134 * A recursive algorithm to optimize the system recalculation selecting only constraints that have changed. Each
1135 * constraint change is propagated to the list of constraints for each variable.
1137 static void lmm_update_modified_set_rec(lmm_system_t sys, lmm_constraint_t cnst)
1141 //TODOLATER: Why lmm_modified_set has been changed in git version 2392B5157...? Looks equivalent logically and less obvious..
1142 xbt_swag_foreach(_elem, &cnst->enabled_element_set) {
1143 lmm_variable_t var = ((lmm_element_t)_elem)->variable;
1144 for (s_lmm_element_t const& elem : var->cnsts) {
1145 if (var->visited == sys->visited_counter)
1147 if (elem.constraint != cnst && not xbt_swag_belongs(elem.constraint, &sys->modified_constraint_set)) {
1148 xbt_swag_insert(elem.constraint, &sys->modified_constraint_set);
1149 lmm_update_modified_set_rec(sys, elem.constraint);
1152 //var will be ignored in later visits as long as sys->visited_counter does not move
1153 var->visited = sys->visited_counter;
1157 static void lmm_update_modified_set(lmm_system_t sys, lmm_constraint_t cnst)
1159 /* nothing to do if selective update isn't active */
1160 if (sys->selective_update_active && not xbt_swag_belongs(cnst, &sys->modified_constraint_set)) {
1161 xbt_swag_insert(cnst, &sys->modified_constraint_set);
1162 lmm_update_modified_set_rec(sys, cnst);
1166 /** \brief Remove all constraints of the modified_constraint_set.
1168 * \param sys the lmm_system_t
1170 static void lmm_remove_all_modified_set(lmm_system_t sys)
1172 // We cleverly un-flag all variables just by incrementing sys->visited_counter
1173 // In effect, the var->visited value will no more be equal to sys->visited counter
1174 // To be clean, when visited counter has wrapped around, we force these var->visited values so that variables that
1175 // were in the modified a long long time ago are not wrongly skipped here, which would lead to very nasty bugs
1176 // (i.e. not readibily reproducible, and requiring a lot of run time before happening).
1177 if (++sys->visited_counter == 1) {
1178 /* the counter wrapped around, reset each variable->visited */
1180 xbt_swag_foreach(_var, &sys->variable_set)
1181 ((lmm_variable_t)_var)->visited = 0;
1183 xbt_swag_reset(&sys->modified_constraint_set);
1187 * Returns resource load (in flop per second, or byte per second, or similar)
1189 * If the resource is shared (the default case), the load is sum of resource usage made by every variables located on
1192 * If the resource is not shared (ie in FATPIPE mode), then the load is the max (not the sum) of all resource usages
1193 * located on this resource.
1195 * \param cnst the lmm_constraint_t associated to the resource
1197 double lmm_constraint_get_usage(lmm_constraint_t cnst) {
1199 xbt_swag_t elem_list = &(cnst->enabled_element_set);
1202 xbt_swag_foreach(_elem, elem_list)
1204 lmm_element_t elem = (lmm_element_t)_elem;
1205 if (elem->consumption_weight > 0) {
1206 if (cnst->sharing_policy)
1207 usage += elem->consumption_weight * elem->variable->value;
1208 else if (usage < elem->consumption_weight * elem->variable->value)
1209 usage = std::max(usage, elem->consumption_weight * elem->variable->value);
1215 int lmm_constraint_get_variable_amount(lmm_constraint_t cnst) {
1217 xbt_swag_t elem_list = &(cnst->enabled_element_set);
1220 xbt_swag_foreach(_elem, elem_list) {
1221 lmm_element_t elem = (lmm_element_t)_elem;
1222 if (elem->consumption_weight > 0)