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[SAMPI] Move ampi signals to simgrid::smpi::plugin::ampi
[simgrid.git] / src / smpi / plugins / sampi_loadbalancer.cpp
1 /* Copyright (c) 2018.      The SimGrid Team. All rights reserved.          */
2
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. */
5
6 #include <simgrid/plugins/load_balancer.h>
7 #include <simgrid/s4u.hpp>
8 #include <simgrid/smpi/replay.hpp>
9 #include <smpi/smpi.h>
10 #include <src/smpi/include/smpi_comm.hpp>
11 #include <src/smpi/include/smpi_actor.hpp>
12 #include <src/smpi/plugins/ampi/instr_ampi.hpp>
13 #include <src/smpi/plugins/ampi/ampi.hpp>
14 #include <xbt/replay.hpp>
15
16 #include "src/kernel/activity/ExecImpl.hpp"
17 #include "src/simix/ActorImpl.hpp"
18 #include <simgrid/smpi/loadbalancer/load_balancer.hpp>
19
20 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(plugin_load_balancer, smpi, "Logging specific to the SMPI load balancing plugin");
21
22 static simgrid::config::Flag<int> cfg_migration_frequency("smpi/plugin/lb/migration-frequency", {"smpi/plugin/lb/migration_frequency"},
23     "After how many calls to the migration function should the migration be actually executed?", 10,
24     [](double val){if (val != 10) sg_load_balancer_plugin_init();});
25
26 namespace simgrid {
27 namespace smpi {
28 namespace plugin {
29
30 static simgrid::plugin::loadbalancer::LoadBalancer lb;
31
32 class MigrateParser : public simgrid::smpi::replay::ActionArgParser {
33 public:
34   double memory_consumption;
35   void parse(simgrid::xbt::ReplayAction& action, std::string name)
36   {
37     // The only parameter is the amount of memory used by the current process.
38     CHECK_ACTION_PARAMS(action, 1, 0);
39     memory_consumption = std::stod(action[2]);
40   }
41 };
42
43 /* This function simulates what happens when the original application calls
44  * (A)MPI_Migrate. It executes the load balancing heuristics, makes the necessary
45  * migrations and updates the task mapping in the load balancer. 
46  */
47 class MigrateAction : public simgrid::smpi::replay::ReplayAction<simgrid::smpi::plugin::MigrateParser> {
48 public:
49   explicit MigrateAction() : ReplayAction("Migrate") {}
50   void kernel(simgrid::xbt::ReplayAction& action)
51   {
52     static std::map<simgrid::s4u::ActorPtr, int> migration_call_counter;
53     static simgrid::s4u::Barrier smpilb_bar(smpi_process_count());
54     simgrid::s4u::Host* cur_host = simgrid::s4u::this_actor::get_host();
55     simgrid::s4u::Host* migrate_to_host;
56
57     TRACE_migration_call(my_proc_id, NULL);
58
59     migration_call_counter[simgrid::s4u::Actor::self()]++;
60     if ((migration_call_counter[simgrid::s4u::Actor::self()] % simgrid::config::get_value<int>(cfg_migration_frequency.get_name())) != 0) {
61       return;
62     }
63
64     // TODO cheinrich: Why do we need this barrier?
65     smpilb_bar.wait();
66
67     static bool was_executed = false;
68     if (not was_executed) {
69       was_executed = true;
70       smpi_bench_begin();
71       XBT_INFO("RUNNING THE LB");
72       lb.run();
73       smpi_bench_end();
74     }
75
76     // This barrier is required to ensure that the mapping has been computed and is available
77     smpilb_bar.wait();
78     was_executed = false; // Must stay behind this barrier so that all processes have passed the if clause
79
80     migrate_to_host = lb.get_mapping();
81     if (cur_host != migrate_to_host) { // Origin and dest are not the same -> migrate
82       sg_host_t migration_hosts[2] = {cur_host, migrate_to_host};
83       // Changing this to double[2] ... will cause trouble with parallel_execute, because that fct is trying to call free().
84       double* comp_amount  = new double[2]{0, 0};
85       double* comm_amount  = new double[4]{0, /*must not be 0*/std::max(args.memory_consumption, 1.0), 0, 0};
86
87       xbt_os_timer_t timer = smpi_process()->timer();
88       xbt_os_threadtimer_start(timer);
89       simgrid::s4u::this_actor::parallel_execute(2, migration_hosts, comp_amount, comm_amount, -1.0);
90       xbt_os_threadtimer_stop(timer);
91       smpi_execute(xbt_os_timer_elapsed(timer));
92
93       // Update the process and host mapping in SimGrid.
94       TRACE_smpi_process_change_host(my_proc_id, migrate_to_host);
95       simgrid::s4u::this_actor::migrate(migrate_to_host);
96     }
97
98     smpilb_bar.wait();
99
100     smpi_bench_begin();
101   }
102 };
103
104 /******************************************************************************
105  *         Code to include the duration of iterations in the trace.           *
106  ******************************************************************************/
107
108 // FIXME Move declaration
109 XBT_PRIVATE void action_iteration_in(simgrid::xbt::ReplayAction& action);
110 void action_iteration_in(simgrid::xbt::ReplayAction& action)
111 {
112   CHECK_ACTION_PARAMS(action, 0, 0)
113   TRACE_Iteration_in(simgrid::s4u::this_actor::get_pid(), nullptr);
114   simgrid::smpi::plugin::ampi::on_iteration_in(MPI_COMM_WORLD->group()->actor(std::stol(action[0])));
115 }
116
117 XBT_PRIVATE void action_iteration_out(simgrid::xbt::ReplayAction& action);
118 void action_iteration_out(simgrid::xbt::ReplayAction& action)
119 {
120   CHECK_ACTION_PARAMS(action, 0, 0)
121   TRACE_Iteration_out(simgrid::s4u::this_actor::get_pid(), nullptr);
122   simgrid::smpi::plugin::ampi::on_iteration_out(MPI_COMM_WORLD->group()->actor(std::stol(action[0])));
123 }
124 }
125 }
126 }
127
128 /** @ingroup plugin_loadbalancer
129  * @brief Initializes the load balancer plugin
130  * @details The load balancer plugin supports several AMPI load balancers that move ranks
131  * around, based on their host's load.
132  */
133 void sg_load_balancer_plugin_init()
134 {
135   static bool done = false;
136   if (!done) {
137     done = true;
138     simgrid::kernel::activity::ExecImpl::on_completion.connect([](simgrid::kernel::activity::ExecImplPtr activity){
139         simgrid::smpi::plugin::lb.record_actor_computation(activity->simcalls_.front()->issuer->iface(), activity->surf_action_->get_cost());
140     });
141
142     xbt_replay_action_register(
143         "migrate", [](simgrid::xbt::ReplayAction& action) { simgrid::smpi::plugin::MigrateAction().execute(action); });
144     xbt_replay_action_register("iteration_in", simgrid::smpi::plugin::action_iteration_in);
145     xbt_replay_action_register("iteration_out", simgrid::smpi::plugin::action_iteration_out);
146   }
147 }