[S4U] Add some tests for upcoming filtering feature

[simgrid.git] / examples / s4u / engine-filtering / s4u-engine-filtering.cpp

diff --git a/examples/s4u/engine-filtering/s4u-engine-filtering.cpp b/examples/s4u/engine-filtering/s4u-engine-filtering.cpp
new file mode 100644 (file)
index 0000000..935f110
--- /dev/null
+++ b/examples/s4u/engine-filtering/s4u-engine-filtering.cpp
@@ -0,0 +1,84 @@
+/* Copyright (c) 2017-2018. The SimGrid Team. All rights reserved.          */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "xbt/log.h"
+#include <simgrid/s4u.hpp>
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(s4u_engine_filtering, "Messages specific for this s4u example");
+
+namespace filter {
+class FrequencyChanged {
+  std::map<simgrid::s4u::Host*, int> host_list;
+
+public:
+  FrequencyChanged(simgrid::s4u::Engine& e) {
+    std::vector<simgrid::s4u::Host*> list = e.get_all_hosts();
+    for (auto& host : list) {
+      host_list.insert({host, host->get_pstate()});
+    }
+  }
+
+  bool operator()(simgrid::s4u::Host* host) { return host->get_pstate() != host_list.at(host); }
+
+  double get_old_speed(simgrid::s4u::Host* host) { return host_list.at(host); }
+};
+class SingleCore {
+public:
+  bool operator()(simgrid::s4u::Host* host) { return host->get_core_count() == 1; }
+};
+
+bool filter_speed_more_than_50Mf(simgrid::s4u::Host* host);
+bool filter_speed_more_than_50Mf(simgrid::s4u::Host* host)
+{
+  return host->getSpeed() > 50E6;
+}
+}
+int main(int argc, char* argv[])
+{
+  simgrid::s4u::Engine e(&argc, argv);
+  e.load_platform(argv[1]);
+
+  /**
+   * Use a lambda function to filter hosts: We only want multicore hosts
+   */
+  XBT_INFO("Hosts currently registered with this engine: %lu", e.get_host_count());
+  std::vector<simgrid::s4u::Host*> list =
+      e.get_filtered_hosts([](simgrid::s4u::Host* host) { return host->get_core_count() > 1; });
+
+  for (auto& host : list)
+    XBT_INFO("The following hosts have more than one core: %s", host->get_cname());
+
+  xbt_assert(list.size() == 1);
+
+  /*
+   * Use a function object (functor) without memory
+   */
+  list = e.get_filtered_hosts(filter::SingleCore());
+
+  for (auto& host : list)
+    XBT_INFO("The following hosts are SingleCore: %s", host->get_cname());
+
+  /**
+   * This just shows how to use a function object that uses
+   * memory to filter.
+   */
+  XBT_INFO("A simple example: Let's retrieve all hosts that changed their frequency");
+  filter::FrequencyChanged filter(e);
+  e.host_by_name("MyHost2")->set_pstate(2);
+  list = e.get_filtered_hosts(filter);
+
+  for (auto& host : list)
+    XBT_INFO("The following hosts changed their frequency: %s (from %.1ff to %.1ff)", host->get_cname(), host->getPstateSpeed(filter.get_old_speed(host)), host->getSpeed());
+
+  /*
+   * You can also just use any normal function (namespaced as well, if you want) to filter
+   */
+  list = e.get_filtered_hosts(filter::filter_speed_more_than_50Mf);
+
+  for (auto& host : list)
+    XBT_INFO("The following hosts have a frequency > 50Mf: %s", host->get_cname());
+
+  return 0;
+}