1 | NAME |
1 | NAME |
2 | AnyEvent - provide framework for multiple event loops |
2 | AnyEvent - the DBI of event loop programming |
3 | |
3 | |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, |
5 | event loops. |
5 | Qt and POE are various supported event loops/environments. |
6 | |
6 | |
7 | SYNOPSIS |
7 | SYNOPSIS |
8 | use AnyEvent; |
8 | use AnyEvent; |
9 | |
9 | |
10 | # file descriptor readable |
10 | # file descriptor readable |
… | |
… | |
37 | |
37 | |
38 | INTRODUCTION/TUTORIAL |
38 | INTRODUCTION/TUTORIAL |
39 | This manpage is mainly a reference manual. If you are interested in a |
39 | This manpage is mainly a reference manual. If you are interested in a |
40 | tutorial or some gentle introduction, have a look at the AnyEvent::Intro |
40 | tutorial or some gentle introduction, have a look at the AnyEvent::Intro |
41 | manpage. |
41 | manpage. |
|
|
42 | |
|
|
43 | SUPPORT |
|
|
44 | There is a mailinglist for discussing all things AnyEvent, and an IRC |
|
|
45 | channel, too. |
|
|
46 | |
|
|
47 | See the AnyEvent project page at the Schmorpforge Ta-Sa Software |
|
|
48 | Repository, at <http://anyevent.schmorp.de>, for more info. |
42 | |
49 | |
43 | WHY YOU SHOULD USE THIS MODULE (OR NOT) |
50 | WHY YOU SHOULD USE THIS MODULE (OR NOT) |
44 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
51 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
45 | nowadays. So what is different about AnyEvent? |
52 | nowadays. So what is different about AnyEvent? |
46 | |
53 | |
… | |
… | |
166 | Note that "my $w; $w =" combination. This is necessary because in Perl, |
173 | Note that "my $w; $w =" combination. This is necessary because in Perl, |
167 | my variables are only visible after the statement in which they are |
174 | my variables are only visible after the statement in which they are |
168 | declared. |
175 | declared. |
169 | |
176 | |
170 | I/O WATCHERS |
177 | I/O WATCHERS |
|
|
178 | $w = AnyEvent->io ( |
|
|
179 | fh => <filehandle_or_fileno>, |
|
|
180 | poll => <"r" or "w">, |
|
|
181 | cb => <callback>, |
|
|
182 | ); |
|
|
183 | |
171 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
184 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
172 | the following mandatory key-value pairs as arguments: |
185 | the following mandatory key-value pairs as arguments: |
173 | |
186 | |
174 | "fh" is the Perl *file handle* (or a naked file descriptor) to watch for |
187 | "fh" is the Perl *file handle* (or a naked file descriptor) to watch for |
175 | events (AnyEvent might or might not keep a reference to this file |
188 | events (AnyEvent might or might not keep a reference to this file |
… | |
… | |
203 | warn "read: $input\n"; |
216 | warn "read: $input\n"; |
204 | undef $w; |
217 | undef $w; |
205 | }); |
218 | }); |
206 | |
219 | |
207 | TIME WATCHERS |
220 | TIME WATCHERS |
|
|
221 | $w = AnyEvent->timer (after => <seconds>, cb => <callback>); |
|
|
222 | |
|
|
223 | $w = AnyEvent->timer ( |
|
|
224 | after => <fractional_seconds>, |
|
|
225 | interval => <fractional_seconds>, |
|
|
226 | cb => <callback>, |
|
|
227 | ); |
|
|
228 | |
208 | You can create a time watcher by calling the "AnyEvent->timer" method |
229 | You can create a time watcher by calling the "AnyEvent->timer" method |
209 | with the following mandatory arguments: |
230 | with the following mandatory arguments: |
210 | |
231 | |
211 | "after" specifies after how many seconds (fractional values are |
232 | "after" specifies after how many seconds (fractional values are |
212 | supported) the callback should be invoked. "cb" is the callback to |
233 | supported) the callback should be invoked. "cb" is the callback to |
… | |
… | |
336 | the event loop's idea of "current time". |
357 | the event loop's idea of "current time". |
337 | |
358 | |
338 | Note that updating the time *might* cause some events to be handled. |
359 | Note that updating the time *might* cause some events to be handled. |
339 | |
360 | |
340 | SIGNAL WATCHERS |
361 | SIGNAL WATCHERS |
|
|
362 | $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>); |
|
|
363 | |
341 | You can watch for signals using a signal watcher, "signal" is the signal |
364 | You can watch for signals using a signal watcher, "signal" is the signal |
342 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
365 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
343 | callback to be invoked whenever a signal occurs. |
366 | callback to be invoked whenever a signal occurs. |
344 | |
367 | |
345 | Although the callback might get passed parameters, their value and |
368 | Although the callback might get passed parameters, their value and |
… | |
… | |
357 | |
380 | |
358 | This watcher might use %SIG (depending on the event loop used), so |
381 | This watcher might use %SIG (depending on the event loop used), so |
359 | programs overwriting those signals directly will likely not work |
382 | programs overwriting those signals directly will likely not work |
360 | correctly. |
383 | correctly. |
361 | |
384 | |
|
|
385 | Example: exit on SIGINT |
|
|
386 | |
|
|
387 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
|
|
388 | |
|
|
389 | Signal Races, Delays and Workarounds |
362 | Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not |
390 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
363 | support attaching callbacks to signals, which is a pity, as you cannot |
391 | callbacks to signals in a generic way, which is a pity, as you cannot do |
364 | do race-free signal handling in perl. AnyEvent will try to do it's best, |
392 | race-free signal handling in perl, requiring C libraries for this. |
365 | but in some cases, signals will be delayed. The maximum time a signal |
393 | AnyEvent will try to do it's best, which means in some cases, signals |
366 | might be delayed is specified in $AnyEvent::MAX_SIGNAL_LATENCY (default: |
394 | will be delayed. The maximum time a signal might be delayed is specified |
367 | 10 seconds). This variable can be changed only before the first signal |
395 | in $AnyEvent::MAX_SIGNAL_LATENCY (default: 10 seconds). This variable |
368 | watcher is created, and should be left alone otherwise. Higher values |
396 | can be changed only before the first signal watcher is created, and |
|
|
397 | should be left alone otherwise. This variable determines how often |
|
|
398 | AnyEvent polls for signals (in case a wake-up was missed). Higher values |
369 | will cause fewer spurious wake-ups, which is better for power and CPU |
399 | will cause fewer spurious wake-ups, which is better for power and CPU |
|
|
400 | saving. |
|
|
401 | |
370 | saving. All these problems can be avoided by installing the optional |
402 | All these problems can be avoided by installing the optional |
371 | Async::Interrupt module. |
403 | Async::Interrupt module, which works with most event loops. It will not |
372 | |
404 | work with inherently broken event loops such as Event or Event::Lib (and |
373 | Example: exit on SIGINT |
405 | not with POE currently, as POE does it's own workaround with one-second |
374 | |
406 | latency). For those, you just have to suffer the delays. |
375 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
|
|
376 | |
407 | |
377 | CHILD PROCESS WATCHERS |
408 | CHILD PROCESS WATCHERS |
|
|
409 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
|
|
410 | |
378 | You can also watch on a child process exit and catch its exit status. |
411 | You can also watch on a child process exit and catch its exit status. |
379 | |
412 | |
380 | The child process is specified by the "pid" argument (if set to 0, it |
413 | The child process is specified by the "pid" argument (one some backends, |
381 | watches for any child process exit). The watcher will triggered only |
414 | using 0 watches for any child process exit, on others this will croak). |
382 | when the child process has finished and an exit status is available, not |
415 | The watcher will be triggered only when the child process has finished |
383 | on any trace events (stopped/continued). |
416 | and an exit status is available, not on any trace events |
|
|
417 | (stopped/continued). |
384 | |
418 | |
385 | The callback will be called with the pid and exit status (as returned by |
419 | The callback will be called with the pid and exit status (as returned by |
386 | waitpid), so unlike other watcher types, you *can* rely on child watcher |
420 | waitpid), so unlike other watcher types, you *can* rely on child watcher |
387 | callback arguments. |
421 | callback arguments. |
388 | |
422 | |
… | |
… | |
427 | |
461 | |
428 | # do something else, then wait for process exit |
462 | # do something else, then wait for process exit |
429 | $done->recv; |
463 | $done->recv; |
430 | |
464 | |
431 | IDLE WATCHERS |
465 | IDLE WATCHERS |
|
|
466 | $w = AnyEvent->idle (cb => <callback>); |
|
|
467 | |
432 | Sometimes there is a need to do something, but it is not so important to |
468 | Sometimes there is a need to do something, but it is not so important to |
433 | do it instantly, but only when there is nothing better to do. This |
469 | do it instantly, but only when there is nothing better to do. This |
434 | "nothing better to do" is usually defined to be "no other events need |
470 | "nothing better to do" is usually defined to be "no other events need |
435 | attention by the event loop". |
471 | attention by the event loop". |
436 | |
472 | |
… | |
… | |
461 | } |
497 | } |
462 | }); |
498 | }); |
463 | }); |
499 | }); |
464 | |
500 | |
465 | CONDITION VARIABLES |
501 | CONDITION VARIABLES |
|
|
502 | $cv = AnyEvent->condvar; |
|
|
503 | |
|
|
504 | $cv->send (<list>); |
|
|
505 | my @res = $cv->recv; |
|
|
506 | |
466 | If you are familiar with some event loops you will know that all of them |
507 | If you are familiar with some event loops you will know that all of them |
467 | require you to run some blocking "loop", "run" or similar function that |
508 | require you to run some blocking "loop", "run" or similar function that |
468 | will actively watch for new events and call your callbacks. |
509 | will actively watch for new events and call your callbacks. |
469 | |
510 | |
470 | AnyEvent is slightly different: it expects somebody else to run the |
511 | AnyEvent is slightly different: it expects somebody else to run the |
… | |
… | |
490 | Condition variables are similar to callbacks, except that you can |
531 | Condition variables are similar to callbacks, except that you can |
491 | optionally wait for them. They can also be called merge points - points |
532 | optionally wait for them. They can also be called merge points - points |
492 | in time where multiple outstanding events have been processed. And yet |
533 | in time where multiple outstanding events have been processed. And yet |
493 | another way to call them is transactions - each condition variable can |
534 | another way to call them is transactions - each condition variable can |
494 | be used to represent a transaction, which finishes at some point and |
535 | be used to represent a transaction, which finishes at some point and |
495 | delivers a result. |
536 | delivers a result. And yet some people know them as "futures" - a |
|
|
537 | promise to compute/deliver something that you can wait for. |
496 | |
538 | |
497 | Condition variables are very useful to signal that something has |
539 | Condition variables are very useful to signal that something has |
498 | finished, for example, if you write a module that does asynchronous http |
540 | finished, for example, if you write a module that does asynchronous http |
499 | requests, then a condition variable would be the ideal candidate to |
541 | requests, then a condition variable would be the ideal candidate to |
500 | signal the availability of results. The user can either act when the |
542 | signal the availability of results. The user can either act when the |
… | |
… | |
534 | after => 1, |
576 | after => 1, |
535 | cb => sub { $result_ready->send }, |
577 | cb => sub { $result_ready->send }, |
536 | ); |
578 | ); |
537 | |
579 | |
538 | # this "blocks" (while handling events) till the callback |
580 | # this "blocks" (while handling events) till the callback |
539 | # calls -<send |
581 | # calls ->send |
540 | $result_ready->recv; |
582 | $result_ready->recv; |
541 | |
583 | |
542 | Example: wait for a timer, but take advantage of the fact that condition |
584 | Example: wait for a timer, but take advantage of the fact that condition |
543 | variables are also callable directly. |
585 | variables are also callable directly. |
544 | |
586 | |
… | |
… | |
601 | into one. For example, a function that pings many hosts in parallel |
643 | into one. For example, a function that pings many hosts in parallel |
602 | might want to use a condition variable for the whole process. |
644 | might want to use a condition variable for the whole process. |
603 | |
645 | |
604 | Every call to "->begin" will increment a counter, and every call to |
646 | Every call to "->begin" will increment a counter, and every call to |
605 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
647 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
606 | (last) callback passed to "begin" will be executed. That callback is |
648 | (last) callback passed to "begin" will be executed, passing the |
607 | *supposed* to call "->send", but that is not required. If no |
649 | condvar as first argument. That callback is *supposed* to call |
|
|
650 | "->send", but that is not required. If no group callback was set, |
608 | callback was set, "send" will be called without any arguments. |
651 | "send" will be called without any arguments. |
609 | |
652 | |
610 | You can think of "$cv->send" giving you an OR condition (one call |
653 | You can think of "$cv->send" giving you an OR condition (one call |
611 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
654 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
612 | condition (all "begin" calls must be "end"'ed before the condvar |
655 | condition (all "begin" calls must be "end"'ed before the condvar |
613 | sends). |
656 | sends). |
… | |
… | |
641 | that are begung can potentially be zero: |
684 | that are begung can potentially be zero: |
642 | |
685 | |
643 | my $cv = AnyEvent->condvar; |
686 | my $cv = AnyEvent->condvar; |
644 | |
687 | |
645 | my %result; |
688 | my %result; |
646 | $cv->begin (sub { $cv->send (\%result) }); |
689 | $cv->begin (sub { shift->send (\%result) }); |
647 | |
690 | |
648 | for my $host (@list_of_hosts) { |
691 | for my $host (@list_of_hosts) { |
649 | $cv->begin; |
692 | $cv->begin; |
650 | ping_host_then_call_callback $host, sub { |
693 | ping_host_then_call_callback $host, sub { |
651 | $result{$host} = ...; |
694 | $result{$host} = ...; |
… | |
… | |
718 | |
761 | |
719 | $cb = $cv->cb ($cb->($cv)) |
762 | $cb = $cv->cb ($cb->($cv)) |
720 | This is a mutator function that returns the callback set and |
763 | This is a mutator function that returns the callback set and |
721 | optionally replaces it before doing so. |
764 | optionally replaces it before doing so. |
722 | |
765 | |
723 | The callback will be called when the condition becomes "true", i.e. |
766 | The callback will be called when the condition becomes (or already |
724 | when "send" or "croak" are called, with the only argument being the |
767 | was) "true", i.e. when "send" or "croak" are called (or were |
725 | condition variable itself. Calling "recv" inside the callback or at |
768 | called), with the only argument being the condition variable itself. |
|
|
769 | Calling "recv" inside the callback or at any later time is |
726 | any later time is guaranteed not to block. |
770 | guaranteed not to block. |
727 | |
771 | |
728 | SUPPORTED EVENT LOOPS/BACKENDS |
772 | SUPPORTED EVENT LOOPS/BACKENDS |
729 | The available backend classes are (every class has its own manpage): |
773 | The available backend classes are (every class has its own manpage): |
730 | |
774 | |
731 | Backends that are autoprobed when no other event loop can be found. |
775 | Backends that are autoprobed when no other event loop can be found. |
732 | EV is the preferred backend when no other event loop seems to be in |
776 | EV is the preferred backend when no other event loop seems to be in |
733 | use. If EV is not installed, then AnyEvent will try Event, and, |
777 | use. If EV is not installed, then AnyEvent will fall back to its own |
734 | failing that, will fall back to its own pure-perl implementation, |
778 | pure-perl implementation, which is available everywhere as it comes |
735 | which is available everywhere as it comes with AnyEvent itself. |
779 | with AnyEvent itself. |
736 | |
780 | |
737 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
781 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
738 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
|
|
739 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
782 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
740 | |
783 | |
741 | Backends that are transparently being picked up when they are used. |
784 | Backends that are transparently being picked up when they are used. |
742 | These will be used when they are currently loaded when the first |
785 | These will be used when they are currently loaded when the first |
743 | watcher is created, in which case it is assumed that the application |
786 | watcher is created, in which case it is assumed that the application |
744 | is using them. This means that AnyEvent will automatically pick the |
787 | is using them. This means that AnyEvent will automatically pick the |
745 | right backend when the main program loads an event module before |
788 | right backend when the main program loads an event module before |
746 | anything starts to create watchers. Nothing special needs to be done |
789 | anything starts to create watchers. Nothing special needs to be done |
747 | by the main program. |
790 | by the main program. |
748 | |
791 | |
|
|
792 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
749 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
793 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
750 | AnyEvent::Impl::Tk based on Tk, very broken. |
794 | AnyEvent::Impl::Tk based on Tk, very broken. |
751 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
795 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
752 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
796 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
|
|
797 | AnyEvent::Impl::Irssi used when running within irssi. |
753 | |
798 | |
754 | Backends with special needs. |
799 | Backends with special needs. |
755 | Qt requires the Qt::Application to be instantiated first, but will |
800 | Qt requires the Qt::Application to be instantiated first, but will |
756 | otherwise be picked up automatically. As long as the main program |
801 | otherwise be picked up automatically. As long as the main program |
757 | instantiates the application before any AnyEvent watchers are |
802 | instantiates the application before any AnyEvent watchers are |
… | |
… | |
822 | creates and installs the global IO::AIO watcher in a "post_detect" |
867 | creates and installs the global IO::AIO watcher in a "post_detect" |
823 | block to avoid autodetecting the event module at load time. |
868 | block to avoid autodetecting the event module at load time. |
824 | |
869 | |
825 | If called in scalar or list context, then it creates and returns an |
870 | If called in scalar or list context, then it creates and returns an |
826 | object that automatically removes the callback again when it is |
871 | object that automatically removes the callback again when it is |
|
|
872 | destroyed (or "undef" when the hook was immediately executed). See |
827 | destroyed. See Coro::BDB for a case where this is useful. |
873 | AnyEvent::AIO for a case where this is useful. |
|
|
874 | |
|
|
875 | Example: Create a watcher for the IO::AIO module and store it in |
|
|
876 | $WATCHER. Only do so after the event loop is initialised, though. |
|
|
877 | |
|
|
878 | our WATCHER; |
|
|
879 | |
|
|
880 | my $guard = AnyEvent::post_detect { |
|
|
881 | $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); |
|
|
882 | }; |
|
|
883 | |
|
|
884 | # the ||= is important in case post_detect immediately runs the block, |
|
|
885 | # as to not clobber the newly-created watcher. assigning both watcher and |
|
|
886 | # post_detect guard to the same variable has the advantage of users being |
|
|
887 | # able to just C<undef $WATCHER> if the watcher causes them grief. |
|
|
888 | |
|
|
889 | $WATCHER ||= $guard; |
828 | |
890 | |
829 | @AnyEvent::post_detect |
891 | @AnyEvent::post_detect |
830 | If there are any code references in this array (you can "push" to it |
892 | If there are any code references in this array (you can "push" to it |
831 | before or after loading AnyEvent), then they will called directly |
893 | before or after loading AnyEvent), then they will called directly |
832 | after the event loop has been chosen. |
894 | after the event loop has been chosen. |
… | |
… | |
971 | Event::ExecFlow |
1033 | Event::ExecFlow |
972 | High level API for event-based execution flow control. |
1034 | High level API for event-based execution flow control. |
973 | |
1035 | |
974 | Coro |
1036 | Coro |
975 | Has special support for AnyEvent via Coro::AnyEvent. |
1037 | Has special support for AnyEvent via Coro::AnyEvent. |
|
|
1038 | |
|
|
1039 | SIMPLIFIED AE API |
|
|
1040 | Starting with version 5.0, AnyEvent officially supports a second, much |
|
|
1041 | simpler, API that is designed to reduce the calling, typing and memory |
|
|
1042 | overhead. |
|
|
1043 | |
|
|
1044 | See the AE manpage for details. |
976 | |
1045 | |
977 | ERROR AND EXCEPTION HANDLING |
1046 | ERROR AND EXCEPTION HANDLING |
978 | In general, AnyEvent does not do any error handling - it relies on the |
1047 | In general, AnyEvent does not do any error handling - it relies on the |
979 | caller to do that if required. The AnyEvent::Strict module (see also the |
1048 | caller to do that if required. The AnyEvent::Strict module (see also the |
980 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
1049 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
… | |
… | |
1305 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1374 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1306 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1375 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1307 | which it is), lets them fire exactly once and destroys them again. |
1376 | which it is), lets them fire exactly once and destroys them again. |
1308 | |
1377 | |
1309 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1378 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1310 | distribution. |
1379 | distribution. It uses the AE interface, which makes a real difference |
|
|
1380 | for the EV and Perl backends only. |
1311 | |
1381 | |
1312 | Explanation of the columns |
1382 | Explanation of the columns |
1313 | *watcher* is the number of event watchers created/destroyed. Since |
1383 | *watcher* is the number of event watchers created/destroyed. Since |
1314 | different event models feature vastly different performances, each event |
1384 | different event models feature vastly different performances, each event |
1315 | loop was given a number of watchers so that overall runtime is |
1385 | loop was given a number of watchers so that overall runtime is |
… | |
… | |
1334 | *destroy* is the time, in microseconds, that it takes to destroy a |
1404 | *destroy* is the time, in microseconds, that it takes to destroy a |
1335 | single watcher. |
1405 | single watcher. |
1336 | |
1406 | |
1337 | Results |
1407 | Results |
1338 | name watchers bytes create invoke destroy comment |
1408 | name watchers bytes create invoke destroy comment |
1339 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1409 | EV/EV 100000 223 0.47 0.43 0.27 EV native interface |
1340 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1410 | EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers |
1341 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1411 | Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal |
1342 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1412 | Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation |
1343 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1413 | Event/Event 16000 516 31.16 31.84 0.82 Event native interface |
1344 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1414 | Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers |
1345 | IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll |
1415 | IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll |
1346 | IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll |
1416 | IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll |
1347 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1417 | Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour |
1348 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1418 | Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers |
1349 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1419 | POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event |
1350 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1420 | POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select |
1351 | |
1421 | |
1352 | Discussion |
1422 | Discussion |
1353 | The benchmark does *not* measure scalability of the event loop very |
1423 | The benchmark does *not* measure scalability of the event loop very |
1354 | well. For example, a select-based event loop (such as the pure perl one) |
1424 | well. For example, a select-based event loop (such as the pure perl one) |
1355 | can never compete with an event loop that uses epoll when the number of |
1425 | can never compete with an event loop that uses epoll when the number of |
… | |
… | |
1366 | benchmark machine, handling an event takes roughly 1600 CPU cycles with |
1436 | benchmark machine, handling an event takes roughly 1600 CPU cycles with |
1367 | EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 |
1437 | EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 |
1368 | CPU cycles with POE. |
1438 | CPU cycles with POE. |
1369 | |
1439 | |
1370 | "EV" is the sole leader regarding speed and memory use, which are both |
1440 | "EV" is the sole leader regarding speed and memory use, which are both |
1371 | maximal/minimal, respectively. Even when going through AnyEvent, it uses |
1441 | maximal/minimal, respectively. When using the AE API there is zero |
|
|
1442 | overhead (when going through the AnyEvent API create is about 5-6 times |
|
|
1443 | slower, with other times being equal, so still uses far less memory than |
1372 | far less memory than any other event loop and is still faster than Event |
1444 | any other event loop and is still faster than Event natively). |
1373 | natively. |
|
|
1374 | |
1445 | |
1375 | The pure perl implementation is hit in a few sweet spots (both the |
1446 | The pure perl implementation is hit in a few sweet spots (both the |
1376 | constant timeout and the use of a single fd hit optimisations in the |
1447 | constant timeout and the use of a single fd hit optimisations in the |
1377 | perl interpreter and the backend itself). Nevertheless this shows that |
1448 | perl interpreter and the backend itself). Nevertheless this shows that |
1378 | it adds very little overhead in itself. Like any select-based backend |
1449 | it adds very little overhead in itself. Like any select-based backend |
… | |
… | |
1448 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which |
1519 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which |
1449 | 100 (1%) are active. This mirrors the activity of large servers with |
1520 | 100 (1%) are active. This mirrors the activity of large servers with |
1450 | many connections, most of which are idle at any one point in time. |
1521 | many connections, most of which are idle at any one point in time. |
1451 | |
1522 | |
1452 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1523 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1453 | distribution. |
1524 | distribution. It uses the AE interface, which makes a real difference |
|
|
1525 | for the EV and Perl backends only. |
1454 | |
1526 | |
1455 | Explanation of the columns |
1527 | Explanation of the columns |
1456 | *sockets* is the number of sockets, and twice the number of "servers" |
1528 | *sockets* is the number of sockets, and twice the number of "servers" |
1457 | (as each server has a read and write socket end). |
1529 | (as each server has a read and write socket end). |
1458 | |
1530 | |
… | |
… | |
1464 | forwarding it to another server. This includes deleting the old timeout |
1536 | forwarding it to another server. This includes deleting the old timeout |
1465 | and creating a new one that moves the timeout into the future. |
1537 | and creating a new one that moves the timeout into the future. |
1466 | |
1538 | |
1467 | Results |
1539 | Results |
1468 | name sockets create request |
1540 | name sockets create request |
1469 | EV 20000 69.01 11.16 |
1541 | EV 20000 62.66 7.99 |
1470 | Perl 20000 73.32 35.87 |
1542 | Perl 20000 68.32 32.64 |
1471 | IOAsync 20000 157.00 98.14 epoll |
1543 | IOAsync 20000 174.06 101.15 epoll |
1472 | IOAsync 20000 159.31 616.06 poll |
1544 | IOAsync 20000 174.67 610.84 poll |
1473 | Event 20000 212.62 257.32 |
1545 | Event 20000 202.69 242.91 |
1474 | Glib 20000 651.16 1896.30 |
1546 | Glib 20000 557.01 1689.52 |
1475 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1547 | POE 20000 341.54 12086.32 uses POE::Loop::Event |
1476 | |
1548 | |
1477 | Discussion |
1549 | Discussion |
1478 | This benchmark *does* measure scalability and overall performance of the |
1550 | This benchmark *does* measure scalability and overall performance of the |
1479 | particular event loop. |
1551 | particular event loop. |
1480 | |
1552 | |
… | |
… | |
1644 | Async::Interrupt |
1716 | Async::Interrupt |
1645 | This slightly arcane module is used to implement fast signal |
1717 | This slightly arcane module is used to implement fast signal |
1646 | handling: To my knowledge, there is no way to do completely |
1718 | handling: To my knowledge, there is no way to do completely |
1647 | race-free and quick signal handling in pure perl. To ensure that |
1719 | race-free and quick signal handling in pure perl. To ensure that |
1648 | signals still get delivered, AnyEvent will start an interval timer |
1720 | signals still get delivered, AnyEvent will start an interval timer |
1649 | to wake up perl (and catch the signals) with soemd elay (default is |
1721 | to wake up perl (and catch the signals) with some delay (default is |
1650 | 10 seconds, look for $AnyEvent::MAX_SIGNAL_LATENCY). |
1722 | 10 seconds, look for $AnyEvent::MAX_SIGNAL_LATENCY). |
1651 | |
1723 | |
1652 | If this module is available, then it will be used to implement |
1724 | If this module is available, then it will be used to implement |
1653 | signal catching, which means that signals will not be delayed, and |
1725 | signal catching, which means that signals will not be delayed, and |
1654 | the event loop will not be interrupted regularly, which is more |
1726 | the event loop will not be interrupted regularly, which is more |
1655 | efficient (And good for battery life on laptops). |
1727 | efficient (And good for battery life on laptops). |
1656 | |
1728 | |
1657 | This affects not just the pure-perl event loop, but also other event |
1729 | This affects not just the pure-perl event loop, but also other event |
1658 | loops that have no signal handling on their own (e.g. Glib, Tk, Qt). |
1730 | loops that have no signal handling on their own (e.g. Glib, Tk, Qt). |
|
|
1731 | |
|
|
1732 | Some event loops (POE, Event, Event::Lib) offer signal watchers |
|
|
1733 | natively, and either employ their own workarounds (POE) or use |
|
|
1734 | AnyEvent's workaround (using $AnyEvent::MAX_SIGNAL_LATENCY). |
|
|
1735 | Installing Async::Interrupt does nothing for those backends. |
1659 | |
1736 | |
1660 | EV This module isn't really "optional", as it is simply one of the |
1737 | EV This module isn't really "optional", as it is simply one of the |
1661 | backend event loops that AnyEvent can use. However, it is simply the |
1738 | backend event loops that AnyEvent can use. However, it is simply the |
1662 | best event loop available in terms of features, speed and stability: |
1739 | best event loop available in terms of features, speed and stability: |
1663 | It supports the AnyEvent API optimally, implements all the watcher |
1740 | It supports the AnyEvent API optimally, implements all the watcher |
… | |
… | |
1674 | operation much. It is purely used for performance. |
1751 | operation much. It is purely used for performance. |
1675 | |
1752 | |
1676 | JSON and JSON::XS |
1753 | JSON and JSON::XS |
1677 | This module is required when you want to read or write JSON data via |
1754 | This module is required when you want to read or write JSON data via |
1678 | AnyEvent::Handle. It is also written in pure-perl, but can take |
1755 | AnyEvent::Handle. It is also written in pure-perl, but can take |
1679 | advantage of the ulta-high-speed JSON::XS module when it is |
1756 | advantage of the ultra-high-speed JSON::XS module when it is |
1680 | installed. |
1757 | installed. |
1681 | |
1758 | |
1682 | In fact, AnyEvent::Handle will use JSON::XS by default if it is |
1759 | In fact, AnyEvent::Handle will use JSON::XS by default if it is |
1683 | installed. |
1760 | installed. |
1684 | |
1761 | |
… | |
… | |
1741 | Event::Lib, Qt, POE. |
1818 | Event::Lib, Qt, POE. |
1742 | |
1819 | |
1743 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1820 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1744 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1821 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1745 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE, |
1822 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE, |
1746 | AnyEvent::Impl::IOAsync. |
1823 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi. |
1747 | |
1824 | |
1748 | Non-blocking file handles, sockets, TCP clients and servers: |
1825 | Non-blocking file handles, sockets, TCP clients and servers: |
1749 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
1826 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
1750 | |
1827 | |
1751 | Asynchronous DNS: AnyEvent::DNS. |
1828 | Asynchronous DNS: AnyEvent::DNS. |