1 /* Copyright (c) 2019-2023. 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 <simgrid/s4u/Host.hpp>
8 #include "src/kernel/activity/CommImpl.hpp"
9 #include "src/kernel/resource/WifiLinkImpl.hpp"
11 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(res_network);
13 namespace simgrid::kernel::resource {
19 WifiLinkImpl::WifiLinkImpl(const std::string& name, const std::vector<double>& bandwidths, lmm::System* system)
20 : StandardLinkImpl(name)
22 this->set_constraint(system->constraint_new(this, 1));
23 for (auto bandwidth : bandwidths)
24 bandwidths_.push_back({bandwidth, 1.0, nullptr});
25 kernel::activity::CommImpl::on_start.connect(&update_bw_comm_start);
26 s4u::Link::on_communication_state_change_cb(&update_bw_comm_end);
29 void WifiLinkImpl::set_host_rate(const s4u::Host* host, int rate_level)
31 host_rates_[host->get_name()] = rate_level;
34 double WifiLinkImpl::get_host_rate(const s4u::Host* host) const
36 auto host_rates_it = host_rates_.find(host->get_name());
38 if (host_rates_it == host_rates_.end())
41 int rate_id = host_rates_it->second;
42 xbt_assert(rate_id >= 0,
43 "Negative host wifi rate levels are invalid but host '%s' uses %d as a rate level on link '%s'",
44 host->get_cname(), rate_id, this->get_cname());
45 xbt_assert(rate_id < (int)bandwidths_.size(),
46 "Link '%s' only has %zu wifi rate levels, so the provided level %d is invalid for host '%s'.",
47 this->get_cname(), bandwidths_.size(), rate_id, host->get_cname());
49 Metric rate = bandwidths_[rate_id];
50 return rate.peak * rate.scale;
53 s4u::Link::SharingPolicy WifiLinkImpl::get_sharing_policy() const
55 return s4u::Link::SharingPolicy::WIFI;
58 size_t WifiLinkImpl::get_host_count() const
60 return host_rates_.size();
63 double WifiLinkImpl::wifi_link_dynamic_sharing(const WifiLinkImpl& link, double /*capacity*/, int /*n*/)
65 double ratio = link.get_max_ratio();
66 XBT_DEBUG("New ratio value concurrency %d: %lf of link capacity on link %s", link.nb_active_flux_, ratio, link.get_name().c_str());
70 void WifiLinkImpl::inc_active_flux()
72 xbt_assert(nb_active_flux_ >= 0, "Negative nb_active_flux should not exist");
76 void WifiLinkImpl::dec_active_flux()
78 xbt_assert(nb_active_flux_ > 0, "Negative nb_active_flux should not exist");
82 void WifiLinkImpl::update_bw_comm_start(const kernel::activity::CommImpl& comm)
84 auto const* actionWifi = dynamic_cast<const simgrid::kernel::resource::WifiLinkAction*>(comm.model_action_);
85 if (actionWifi == nullptr)
88 if (auto* link_src = actionWifi->get_src_link()) {
89 link_src->inc_active_flux();
91 if (auto* link_dst = actionWifi->get_dst_link()) {
92 link_dst->inc_active_flux();
96 void WifiLinkImpl::update_bw_comm_end(const simgrid::kernel::resource::NetworkAction& action,
97 simgrid::kernel::resource::Action::State /*state*/)
99 if (action.get_state() != kernel::resource::Action::State::FINISHED)
102 auto const* actionWifi = dynamic_cast<const simgrid::kernel::resource::WifiLinkAction*>(&action);
103 if (actionWifi == nullptr)
106 if (auto* link_src = actionWifi->get_src_link()) {
107 link_src->dec_active_flux();
109 if (auto* link_dst = actionWifi->get_dst_link()) {
110 link_dst->dec_active_flux();
114 double WifiLinkImpl::get_max_ratio() const
117 if (nb_active_flux_ > conc_lim_) {
118 new_peak = (nb_active_flux_-conc_lim_) * co_acc_ + x0_;
119 XBT_DEBUG("Wi-Fi link peak=(%d-%d)*%lf+%lf=%lf", nb_active_flux_, conc_lim_, co_acc_, x0_, new_peak);
122 XBT_DEBUG("Wi-Fi link peak=%lf", x0_);
124 // should be the new maximum bandwidth ratio (comparison between max throughput without concurrency and with it)
125 double propCap = new_peak / x0_;
130 bool WifiLinkImpl::toggle_callback()
132 if (not use_callback_) {
133 XBT_DEBUG("Activate throughput reduction mechanism");
134 use_callback_ = true;
135 this->set_sharing_policy(
136 simgrid::s4u::Link::SharingPolicy::WIFI,
137 std::bind(&wifi_link_dynamic_sharing, std::cref(*this), std::placeholders::_1, std::placeholders::_2));
139 return use_callback_;
142 void WifiLinkImpl::set_latency(double value)
144 xbt_assert(value == 0, "Latency cannot be set for WiFi Links.");
146 } // namespace simgrid::kernel::resource