1 /* Copyright (c) 2019-2022. 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/resource/WifiLinkImpl.hpp"
9 #include "src/surf/surf_interface.hpp"
10 #include "src/kernel/activity/CommImpl.hpp"
12 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(res_network);
14 namespace simgrid::kernel::resource {
20 WifiLinkImpl::WifiLinkImpl(const std::string& name, const std::vector<double>& bandwidths, lmm::System* system)
21 : StandardLinkImpl(name)
23 this->set_constraint(system->constraint_new(this, 1));
24 for (auto bandwidth : bandwidths)
25 bandwidths_.push_back({bandwidth, 1.0, nullptr});
26 kernel::activity::CommImpl::on_start.connect(&update_bw_comm_start);
27 s4u::Link::on_communication_state_change_cb(&update_bw_comm_end);
30 void WifiLinkImpl::set_host_rate(const s4u::Host* host, int rate_level)
32 host_rates_[host->get_name()] = rate_level;
35 double WifiLinkImpl::get_host_rate(const s4u::Host* host) const
37 auto host_rates_it = host_rates_.find(host->get_name());
39 if (host_rates_it == host_rates_.end())
42 int rate_id = host_rates_it->second;
43 xbt_assert(rate_id >= 0,
44 "Negative host wifi rate levels are invalid but host '%s' uses %d as a rate level on link '%s'",
45 host->get_cname(), rate_id, this->get_cname());
46 xbt_assert(rate_id < (int)bandwidths_.size(),
47 "Link '%s' only has %zu wifi rate levels, so the provided level %d is invalid for host '%s'.",
48 this->get_cname(), bandwidths_.size(), rate_id, host->get_cname());
50 Metric rate = bandwidths_[rate_id];
51 return rate.peak * rate.scale;
54 s4u::Link::SharingPolicy WifiLinkImpl::get_sharing_policy() const
56 return s4u::Link::SharingPolicy::WIFI;
59 size_t WifiLinkImpl::get_host_count() const
61 return host_rates_.size();
64 double WifiLinkImpl::wifi_link_dynamic_sharing(const WifiLinkImpl& link, double /*capacity*/, int /*n*/)
66 double ratio = link.get_max_ratio();
67 XBT_DEBUG("New ratio value concurrency %d: %lf of link capacity on link %s", link.nb_active_flux_, ratio, link.get_name().c_str());
71 void WifiLinkImpl::inc_active_flux()
73 xbt_assert(nb_active_flux_ >= 0, "Negative nb_active_flux should not exist");
77 void WifiLinkImpl::dec_active_flux()
79 xbt_assert(nb_active_flux_ > 0, "Negative nb_active_flux should not exist");
83 void WifiLinkImpl::update_bw_comm_start(const kernel::activity::CommImpl& comm)
85 auto const* actionWifi = dynamic_cast<const simgrid::kernel::resource::WifiLinkAction*>(comm.surf_action_);
86 if (actionWifi == nullptr)
89 if (auto* link_src = actionWifi->get_src_link()) {
90 link_src->inc_active_flux();
92 if (auto* link_dst = actionWifi->get_dst_link()) {
93 link_dst->inc_active_flux();
97 void WifiLinkImpl::update_bw_comm_end(const simgrid::kernel::resource::NetworkAction& action,
98 simgrid::kernel::resource::Action::State /*state*/)
100 if (action.get_state() != kernel::resource::Action::State::FINISHED)
103 auto const* actionWifi = dynamic_cast<const simgrid::kernel::resource::WifiLinkAction*>(&action);
104 if (actionWifi == nullptr)
107 if (auto* link_src = actionWifi->get_src_link()) {
108 link_src->dec_active_flux();
110 if (auto* link_dst = actionWifi->get_dst_link()) {
111 link_dst->dec_active_flux();
115 double WifiLinkImpl::get_max_ratio() const
118 if (nb_active_flux_ > conc_lim_) {
119 new_peak = (nb_active_flux_-conc_lim_) * co_acc_ + x0_;
120 XBT_DEBUG("Wi-Fi link peak=(%d-%d)*%lf+%lf=%lf", nb_active_flux_, conc_lim_, co_acc_, x0_, new_peak);
123 XBT_DEBUG("Wi-Fi link peak=%lf", x0_);
125 // should be the new maximum bandwidth ratio (comparison between max throughput without concurrency and with it)
126 double propCap = new_peak / x0_;
131 bool WifiLinkImpl::toggle_callback()
133 if (not use_callback_) {
134 XBT_DEBUG("Activate throughput reduction mechanism");
135 use_callback_ = true;
136 this->set_sharing_policy(
137 simgrid::s4u::Link::SharingPolicy::WIFI,
138 std::bind(&wifi_link_dynamic_sharing, std::cref(*this), std::placeholders::_1, std::placeholders::_2));
140 return use_callback_;
143 void WifiLinkImpl::set_latency(double value)
145 xbt_assert(value == 0, "Latency cannot be set for WiFi Links.");
147 } // namespace simgrid::kernel::resource