1 /* Copyright (c) 2007-2023. 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 #include "src/kernel/lmm/fair_bottleneck.hpp"
7 #include "src/simgrid/math_utils.h"
8 #include "xbt/sysdep.h"
14 #include <xbt/utility.hpp>
16 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(ker_lmm);
18 void simgrid::kernel::lmm::FairBottleneck::do_solve()
20 XBT_DEBUG("Variable set : %zu", variable_set.size());
21 for (Variable& var : variable_set) {
23 XBT_DEBUG("Handling variable %p", &var);
24 if (var.sharing_penalty_ > 0.0 && std::find_if(begin(var.cnsts_), end(var.cnsts_), [](Element const& x) {
25 return x.consumption_weight != 0.0;
26 }) != end(var.cnsts_)) {
27 saturated_variable_set.push_back(var);
29 XBT_DEBUG("Err, finally, there is no need to take care of variable %p", &var);
30 if (var.sharing_penalty_ > 0.0)
35 XBT_DEBUG("Active constraints : %zu", active_constraint_set.size());
36 saturated_constraint_set.insert(saturated_constraint_set.end(), active_constraint_set.begin(),
37 active_constraint_set.end());
38 for (Constraint& cnst : saturated_constraint_set) {
39 cnst.remaining_ = cnst.bound_;
43 XBT_DEBUG("Fair bottleneck Initialized");
46 * Compute Usage and store the variables that reach the maximum.
48 auto& var_list = saturated_variable_set;
49 auto& cnst_list = saturated_constraint_set;
51 if (XBT_LOG_ISENABLED(ker_lmm, xbt_log_priority_debug)) {
52 XBT_DEBUG("Fair bottleneck done");
55 XBT_DEBUG("******* Constraints to process: %zu *******", cnst_list.size());
56 for (auto iter = std::begin(cnst_list); iter != std::end(cnst_list);) {
57 Constraint& cnst = *iter;
59 XBT_DEBUG("Processing cnst %p ", &cnst);
61 for (const Element& elem : cnst.enabled_element_set_) {
62 xbt_assert(elem.variable->sharing_penalty_ > 0);
63 if (elem.consumption_weight > 0 && elem.variable->saturated_variable_set_hook_.is_linked())
66 XBT_DEBUG("\tThere are %d variables", nb);
67 if (nb > 0 && cnst.sharing_policy_ == Constraint::SharingPolicy::FATPIPE)
70 cnst.remaining_ = 0.0;
72 iter = cnst_list.erase(iter);
74 cnst.usage_ = cnst.remaining_ / nb;
75 XBT_DEBUG("\tConstraint Usage %p : %f with %d variables", &cnst, cnst.usage_, nb);
80 for (auto iter = std::begin(var_list); iter != std::end(var_list);) {
81 Variable& var = *iter;
82 double min_inc = DBL_MAX;
83 for (Element const& elm : var.cnsts_) {
84 if (elm.consumption_weight > 0)
85 min_inc = std::min(min_inc, elm.constraint->usage_ / elm.consumption_weight);
88 min_inc = std::min(min_inc, var.bound_ - var.value_);
90 XBT_DEBUG("Updating variable %p maximum increment: %g", &var, var.mu_);
91 var.value_ += var.mu_;
92 if (var.value_ == var.bound_)
93 iter = var_list.erase(iter);
98 for (auto iter = std::begin(cnst_list); iter != std::end(cnst_list);) {
99 Constraint& cnst = *iter;
100 XBT_DEBUG("Updating cnst %p ", &cnst);
101 if (cnst.sharing_policy_ != Constraint::SharingPolicy::FATPIPE) {
102 for (const Element& elem : cnst.enabled_element_set_) {
103 xbt_assert(elem.variable->sharing_penalty_ > 0);
104 XBT_DEBUG("\tUpdate constraint %p (%g) with variable %p by %g", &cnst, cnst.remaining_, elem.variable,
106 double_update(&cnst.remaining_, elem.consumption_weight * elem.variable->mu_, sg_precision_workamount);
109 for (const Element& elem : cnst.enabled_element_set_) {
110 xbt_assert(elem.variable->sharing_penalty_ > 0);
111 XBT_DEBUG("\tNon-Shared variable. Update constraint usage of %p (%g) with variable %p by %g", &cnst,
112 cnst.usage_, elem.variable, elem.variable->mu_);
113 cnst.usage_ = std::min(cnst.usage_, elem.consumption_weight * elem.variable->mu_);
115 XBT_DEBUG("\tUpdate constraint %p (%g) by %g", &cnst, cnst.remaining_, cnst.usage_);
116 double_update(&cnst.remaining_, cnst.usage_, sg_precision_workamount);
119 XBT_DEBUG("\tRemaining for %p : %g", &cnst, cnst.remaining_);
120 if (cnst.remaining_ <= 0.0) {
121 XBT_DEBUG("\tGet rid of constraint %p", &cnst);
123 iter = cnst_list.erase(iter);
124 for (const Element& elem : cnst.enabled_element_set_) {
125 if (elem.variable->sharing_penalty_ <= 0)
127 if (elem.consumption_weight > 0 && elem.variable->saturated_variable_set_hook_.is_linked()) {
128 XBT_DEBUG("\t\tGet rid of variable %p", elem.variable);
129 simgrid::xbt::intrusive_erase(var_list, *elem.variable);
136 } while (not var_list.empty());