1 /* Copyright (c) 2006-2020. 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 #ifndef SIMGRID_S4U_ACTOR_HPP
7 #define SIMGRID_S4U_ACTOR_HPP
9 #include <simgrid/forward.h>
11 #include <simgrid/chrono.hpp>
12 #include <xbt/Extendable.hpp>
13 #include <xbt/functional.hpp>
14 #include <xbt/signal.hpp>
15 #include <xbt/string.hpp>
18 #include <map> // deprecated wrappers
19 #include <unordered_map>
24 /** An actor is an independent stream of execution in your distributed application.
27 * It is located on a (simulated) :cpp:class:`host <simgrid::s4u::Host>`, but can interact
28 * with the whole simulated platform.
30 * You can think of an actor as a process in your distributed application, or as a thread in a multithreaded program.
31 * This is the only component in SimGrid that actually does something on its own, executing its own code.
32 * A resource will not get used if you don't schedule activities on them. This is the code of Actors that create and
33 * schedule these activities. **Please refer to the** :ref:`examples <s4u_ex_actors>` **for more information.**
35 * This API is strongly inspired from the C++11 threads.
36 * The `documentation of this standard <http://en.cppreference.com/w/cpp/thread>`_
37 * may help to understand the philosophy of the SimGrid actors.
40 class XBT_PUBLIC Actor : public xbt::Extendable<Actor> {
44 friend kernel::actor::ActorImpl;
45 friend kernel::activity::MailboxImpl;
47 kernel::actor::ActorImpl* const pimpl_;
50 explicit Actor(smx_actor_t pimpl) : pimpl_(pimpl) {}
54 // ***** No copy *****
55 Actor(Actor const&) = delete;
56 Actor& operator=(Actor const&) = delete;
58 // ***** Reference count *****
59 friend XBT_PUBLIC void intrusive_ptr_add_ref(const Actor* actor);
60 friend XBT_PUBLIC void intrusive_ptr_release(const Actor* actor);
62 /** Retrieve the amount of references on that object. Useful to debug the automatic refcounting */
65 // ***** Actor creation *****
66 /** Retrieve a reference to myself */
69 /** Fired when a new actor has been created **/
70 static xbt::signal<void(Actor&)> on_creation;
71 /** Signal to others that an actor has been suspended**/
72 static xbt::signal<void(Actor const&)> on_suspend;
73 /** Signal to others that an actor has been resumed **/
74 static xbt::signal<void(Actor const&)> on_resume;
75 /** Signal to others that an actor is sleeping **/
76 static xbt::signal<void(Actor const&)> on_sleep;
77 /** Signal to others that an actor wakes up for a sleep **/
78 static xbt::signal<void(Actor const&)> on_wake_up;
79 /** Signal to others that an actor is has been migrated to another host **/
80 static xbt::signal<void(Actor const&, Host const& previous_location)> on_host_change;
82 static xbt::signal<void(Actor const&)> on_migration_start; // XBT_ATTRIB_DEPRECATED_v329
83 static xbt::signal<void(Actor const&)> on_migration_end; // XBT_ATTRIB_DEPRECATED_v329
86 /** Signal indicating that an actor terminated its code.
88 * The actor may continue to exist if it is still referenced in the simulation, but it's not active anymore.
89 * If you want to free extra data when the actor's destructor is called, use :cpp:var:`Actor::on_destruction`.
90 * If you want to register to the termination of a given actor, use :cpp:func:`this_actor::on_exit()` instead.
93 static xbt::signal<void(Actor const&)> on_termination;
94 /** Signal indicating that an actor is about to disappear (its destructor was called).
95 * This signal is fired for any destructed actor, which is mostly useful when designing plugins and extensions.
96 * If you want to react to the end of the actor's code, use Actor::on_termination instead.
97 * If you want to register to the termination of a given actor, use this_actor::on_exit() instead.*/
98 static xbt::signal<void(Actor const&)> on_destruction;
100 /** Create an actor from a std::function<void()>.
101 * If the actor is restarted, it gets a fresh copy of the function. */
102 static ActorPtr create(const std::string& name, s4u::Host* host, const std::function<void()>& code);
103 /** Create an actor, but don't start it yet.
105 * This is usefull to set some properties or extension before actually starting it */
106 static ActorPtr init(const std::string& name, s4u::Host* host);
107 /** Start a previously initialized actor */
108 ActorPtr start(const std::function<void()>& code);
110 /** Create an actor from a callable thing. */
111 template <class F> static ActorPtr create(const std::string& name, s4u::Host* host, F code)
113 return create(name, host, std::function<void()>(std::move(code)));
116 /** Create an actor using a callable thing and its arguments.
118 * Note that the arguments will be copied, so move-only parameters are forbidden */
119 template <class F, class... Args,
120 // This constructor is enabled only if the call code(args...) is valid:
121 typename = typename std::result_of<F(Args...)>::type>
122 static ActorPtr create(const std::string& name, s4u::Host* host, F code, Args... args)
124 return create(name, host, std::bind(std::move(code), std::move(args)...));
127 /** Create actor from function name and a vector of strings as arguments. */
128 static ActorPtr create(const std::string& name, s4u::Host* host, const std::string& function,
129 std::vector<std::string> args);
131 // ***** Methods *****
132 /** This actor will be automatically terminated when the last non-daemon actor finishes **/
135 /** Returns whether or not this actor has been daemonized or not **/
136 bool is_daemon() const;
138 /** Retrieves the name of that actor as a C++ string */
139 const simgrid::xbt::string& get_name() const;
140 /** Retrieves the name of that actor as a C string */
141 const char* get_cname() const;
142 /** Retrieves the host on which that actor is running */
143 Host* get_host() const;
144 /** Retrieves the actor ID of that actor */
145 aid_t get_pid() const;
146 /** Retrieves the actor ID of that actor's creator */
147 aid_t get_ppid() const;
149 /** Suspend an actor, that is blocked until resumeed by another actor */
152 /** Resume an actor that was previously suspended */
155 /** Returns true if the actor is suspended. */
158 /** If set to true, the actor will automatically restart when its host reboots */
159 void set_auto_restart(bool autorestart);
161 /** Add a function to the list of "on_exit" functions for the current actor. The on_exit functions are the functions
162 * executed when your actor is killed. You should use them to free the data used by your actor.
164 * Please note that functions registered in this signal cannot do any simcall themselves. It means that they cannot
165 * send or receive messages, acquire or release mutexes, nor even modify a host property or something. Not only are
166 * blocking functions forbidden in this setting, but also modifications to the global state.
168 * The parameter of on_exit's callbacks denotes whether or not the actor's execution failed.
169 * It will be set to true if the actor was killed or failed because of an exception,
170 * while it will remain to false if the actor terminated gracefully.
172 void on_exit(const std::function<void(bool /*failed*/)>& fun) const;
174 /** Sets the time at which that actor should be killed */
175 void set_kill_time(double time);
176 /** Retrieves the time at which that actor will be killed (or -1 if not set) */
177 double get_kill_time();
179 /** @brief Moves the actor to another host
181 * If the actor is currently blocked on an execution activity, the activity is also
182 * migrated to the new host. If it's blocked on another kind of activity, an error is
183 * raised as the mandated code is not written yet. Please report that bug if you need it.
185 * Asynchronous activities started by the actor are not migrated automatically, so you have
186 * to take care of this yourself (only you knows which ones should be migrated).
188 void set_host(Host* new_host);
190 XBT_ATTRIB_DEPRECATED_v329("Please use set_host() instead") void migrate(Host* new_host) { set_host(new_host); }
193 /** Ask the actor to die.
195 * Any blocking activity will be canceled, and it will be rescheduled to free its memory.
196 * Being killed is not something that actors can defer or avoid.
200 /** Retrieves the actor that have the given PID (or nullptr if not existing) */
201 static ActorPtr by_pid(aid_t pid);
203 /** Wait for the actor to finish.
205 * Blocks the calling actor until the joined actor is terminated. If actor alice executes bob.join(), then alice is
206 * blocked until bob terminates.
210 /** Wait for the actor to finish, or for the timeout to elapse.
212 * Blocks the calling actor until the joined actor is terminated. If actor alice executes bob.join(), then alice is
213 * blocked until bob terminates.
215 void join(double timeout);
216 /** Kill that actor and restart it from start. */
219 /** Kill all actors (but the issuer). Being killed is not something that actors can delay or avoid. */
220 static void kill_all();
222 /** Returns the internal implementation of this actor */
223 kernel::actor::ActorImpl* get_impl() const { return pimpl_; }
225 /** Retrieve the property value (or nullptr if not set) */
226 const std::unordered_map<std::string, std::string>*
227 get_properties() const; // FIXME: do not export the map, but only the keys or something
228 const char* get_property(const std::string& key) const;
229 void set_property(const std::string& key, const std::string& value);
233 * @brief Static methods working on the current actor (see @ref s4u::Actor) */
234 namespace this_actor {
236 XBT_PUBLIC bool is_maestro();
238 /** Block the current actor sleeping for that amount of seconds */
239 XBT_PUBLIC void sleep_for(double duration);
240 /** Block the current actor sleeping until the specified timestamp */
241 XBT_PUBLIC void sleep_until(double wakeup_time);
243 template <class Rep, class Period> inline void sleep_for(std::chrono::duration<Rep, Period> duration)
245 auto seconds = std::chrono::duration_cast<SimulationClockDuration>(duration);
246 this_actor::sleep_for(seconds.count());
249 template <class Duration> inline void sleep_until(const SimulationTimePoint<Duration>& wakeup_time)
251 auto timeout_native = std::chrono::time_point_cast<SimulationClockDuration>(wakeup_time);
252 this_actor::sleep_until(timeout_native.time_since_epoch().count());
255 /** Block the current actor, computing the given amount of flops */
256 XBT_PUBLIC void execute(double flop);
258 /** Block the current actor, computing the given amount of flops at the given priority.
259 * An execution of priority 2 computes twice as fast as an execution at priority 1. */
260 XBT_PUBLIC void execute(double flop, double priority);
263 * @example examples/s4u/exec-ptask/s4u-exec-ptask.cpp
266 /** Block the current actor until the built parallel execution terminates
269 * .. _API_s4u_parallel_execute:
271 * **Example of use:** `examples/s4u/exec-ptask/s4u-exec-ptask.cpp
272 * <https://framagit.org/simgrid/simgrid/tree/master/examples/s4u/exec-ptask/s4u-exec-ptask.cpp>`_
274 * Parallel executions convenient abstractions of parallel computational kernels that span over several machines,
275 * such as a PDGEM and the other ScaLAPACK routines. If you are interested in the effects of such parallel kernel
276 * on the platform (e.g. to schedule them wisely), there is no need to model them in all details of their internal
277 * execution and communications. It is much more convenient to model them as a single execution activity that spans
278 * over several hosts. This is exactly what s4u's Parallel Executions are.
280 * To build such an object, you need to provide a list of hosts that are involved in the parallel kernel (the
281 * actor's own host may or may not be in this list) and specify the amount of computations that should be done by
282 * each host, using a vector of flops amount. Then, you should specify the amount of data exchanged between each
283 * hosts during the parallel kernel. For that, a matrix of values is expected.
285 * It is OK to build a parallel execution without any computation and/or without any communication.
286 * Just pass an empty vector to the corresponding parameter.
288 * For example, if your list of hosts is ``[host0, host1]``, passing a vector ``[1000, 2000]`` as a `flops_amount`
289 * vector means that `host0` should compute 1000 flops while `host1` will compute 2000 flops. A matrix of
290 * communications' sizes of ``[0, 1, 2, 3]`` specifies the following data exchanges:
292 * +-----------+-------+------+
293 * |from \\ to | host0 | host1|
294 * +===========+=======+======+
296 * +-----------+-------+------+
298 * +-----------+-------+------+
300 * - From host0 to host0: 0 bytes are exchanged
301 * - From host0 to host1: 1 byte is exchanged
302 * - From host1 to host0: 2 bytes are exchanged
303 * - From host1 to host1: 3 bytes are exchanged
305 * In a parallel execution, all parts (all executions on each hosts, all communications) progress exactly at the
306 * same pace, so they all terminate at the exact same pace. If one part is slow because of a slow resource or
307 * because of contention, this slows down the parallel execution as a whole.
309 * These objects are somewhat surprising from a modeling point of view. For example, the unit of their speed is
310 * somewhere between flop/sec and byte/sec. Arbitrary parallel executions will simply not work with the usual platform
311 * models, and you must :ref:`use the ptask_L07 host model <options_model_select>` for that. Note that you can mix
312 * regular executions and communications with parallel executions, provided that the host model is ptask_L07.
316 /** Block the current actor until the built parallel execution completes */
317 XBT_PUBLIC void parallel_execute(const std::vector<s4u::Host*>& hosts, const std::vector<double>& flops_amounts,
318 const std::vector<double>& bytes_amounts);
320 XBT_ATTRIB_DEPRECATED_v329("Please use exec_init(...)->wait_for(timeout)") XBT_PUBLIC
321 void parallel_execute(const std::vector<s4u::Host*>& hosts, const std::vector<double>& flops_amounts,
322 const std::vector<double>& bytes_amounts, double timeout);
324 /** Initialize a sequential execution that must then be started manually */
325 XBT_PUBLIC ExecPtr exec_init(double flops_amounts);
326 /** Initialize a parallel execution that must then be started manually */
327 XBT_PUBLIC ExecPtr exec_init(const std::vector<s4u::Host*>& hosts, const std::vector<double>& flops_amounts,
328 const std::vector<double>& bytes_amounts);
330 XBT_PUBLIC ExecPtr exec_async(double flops_amounts);
332 /** @brief Returns the actor ID of the current actor. */
333 XBT_PUBLIC aid_t get_pid();
335 /** @brief Returns the ancestor's actor ID of the current actor. */
336 XBT_PUBLIC aid_t get_ppid();
338 /** @brief Returns the name of the current actor. */
339 XBT_PUBLIC std::string get_name();
340 /** @brief Returns the name of the current actor as a C string. */
341 XBT_PUBLIC const char* get_cname();
343 /** @brief Returns the name of the host on which the current actor is running. */
344 XBT_PUBLIC Host* get_host();
346 /** @brief Suspend the current actor, that is blocked until resume()ed by another actor. */
347 XBT_PUBLIC void suspend();
349 /** @brief Yield the current actor. */
350 XBT_PUBLIC void yield();
352 /** @brief Resume the current actor, that was suspend()ed previously. */
353 XBT_PUBLIC void resume();
355 /** @brief kill the current actor. */
356 XBT_PUBLIC void exit();
358 /** @brief Add a function to the list of "on_exit" functions of the current actor.
360 * The on_exit functions are the functions executed when your actor is killed. You should use them to free the data used
363 * Please note that functions registered in this signal cannot do any simcall themselves. It means that they cannot
364 * send or receive messages, acquire or release mutexes, nor even modify a host property or something. Not only are
365 * blocking functions forbidden in this setting, but also modifications to the global state.
367 * The parameter of on_exit's callbacks denotes whether or not the actor's execution failed.
368 * It will be set to true if the actor was killed or failed because of an exception,
369 * while it will remain to false if the actor terminated gracefully.
372 XBT_PUBLIC void on_exit(const std::function<void(bool)>& fun);
374 /** @brief Migrate the current actor to a new host. */
375 XBT_PUBLIC void set_host(Host* new_host);
377 XBT_ATTRIB_DEPRECATED_v329("Please use set_host() instead") XBT_PUBLIC void migrate(Host* new_host);
382 }} // namespace simgrid::s4u
385 #endif /* SIMGRID_S4U_ACTOR_HPP */