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 | |
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10 | # if you prefer function calls, look at the L<AE> manpage for |
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11 | # an alternative API. |
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12 | |
10 | # file descriptor readable |
13 | # file handle or descriptor readable |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
14 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
12 | |
15 | |
13 | # one-shot or repeating timers |
16 | # one-shot or repeating timers |
14 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
17 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
15 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
18 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
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37 | |
40 | |
38 | INTRODUCTION/TUTORIAL |
41 | INTRODUCTION/TUTORIAL |
39 | This manpage is mainly a reference manual. If you are interested in a |
42 | 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 |
43 | tutorial or some gentle introduction, have a look at the AnyEvent::Intro |
41 | manpage. |
44 | manpage. |
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45 | |
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46 | SUPPORT |
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47 | There is a mailinglist for discussing all things AnyEvent, and an IRC |
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48 | channel, too. |
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49 | |
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50 | See the AnyEvent project page at the Schmorpforge Ta-Sa Software |
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51 | Repository, at <http://anyevent.schmorp.de>, for more info. |
42 | |
52 | |
43 | WHY YOU SHOULD USE THIS MODULE (OR NOT) |
53 | WHY YOU SHOULD USE THIS MODULE (OR NOT) |
44 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
54 | Glib, POE, IO::Async, Event... CPAN offers event models by the dozen |
45 | nowadays. So what is different about AnyEvent? |
55 | nowadays. So what is different about AnyEvent? |
46 | |
56 | |
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166 | Note that "my $w; $w =" combination. This is necessary because in Perl, |
176 | 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 |
177 | my variables are only visible after the statement in which they are |
168 | declared. |
178 | declared. |
169 | |
179 | |
170 | I/O WATCHERS |
180 | I/O WATCHERS |
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181 | $w = AnyEvent->io ( |
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182 | fh => <filehandle_or_fileno>, |
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183 | poll => <"r" or "w">, |
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184 | cb => <callback>, |
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185 | ); |
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186 | |
171 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
187 | You can create an I/O watcher by calling the "AnyEvent->io" method with |
172 | the following mandatory key-value pairs as arguments: |
188 | the following mandatory key-value pairs as arguments: |
173 | |
189 | |
174 | "fh" is the Perl *file handle* (or a naked file descriptor) to watch for |
190 | "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 |
191 | events (AnyEvent might or might not keep a reference to this file |
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203 | warn "read: $input\n"; |
219 | warn "read: $input\n"; |
204 | undef $w; |
220 | undef $w; |
205 | }); |
221 | }); |
206 | |
222 | |
207 | TIME WATCHERS |
223 | TIME WATCHERS |
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224 | $w = AnyEvent->timer (after => <seconds>, cb => <callback>); |
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225 | |
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226 | $w = AnyEvent->timer ( |
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227 | after => <fractional_seconds>, |
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228 | interval => <fractional_seconds>, |
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229 | cb => <callback>, |
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230 | ); |
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231 | |
208 | You can create a time watcher by calling the "AnyEvent->timer" method |
232 | You can create a time watcher by calling the "AnyEvent->timer" method |
209 | with the following mandatory arguments: |
233 | with the following mandatory arguments: |
210 | |
234 | |
211 | "after" specifies after how many seconds (fractional values are |
235 | "after" specifies after how many seconds (fractional values are |
212 | supported) the callback should be invoked. "cb" is the callback to |
236 | supported) the callback should be invoked. "cb" is the callback to |
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333 | time, which might affect timers and time-outs. |
357 | time, which might affect timers and time-outs. |
334 | |
358 | |
335 | When this is the case, you can call this method, which will update |
359 | When this is the case, you can call this method, which will update |
336 | the event loop's idea of "current time". |
360 | the event loop's idea of "current time". |
337 | |
361 | |
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362 | A typical example would be a script in a web server (e.g. |
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363 | "mod_perl") - when mod_perl executes the script, then the event loop |
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364 | will have the wrong idea about the "current time" (being potentially |
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365 | far in the past, when the script ran the last time). In that case |
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366 | you should arrange a call to "AnyEvent->now_update" each time the |
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367 | web server process wakes up again (e.g. at the start of your script, |
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368 | or in a handler). |
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369 | |
338 | Note that updating the time *might* cause some events to be handled. |
370 | Note that updating the time *might* cause some events to be handled. |
339 | |
371 | |
340 | SIGNAL WATCHERS |
372 | SIGNAL WATCHERS |
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373 | $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>); |
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374 | |
341 | You can watch for signals using a signal watcher, "signal" is the signal |
375 | 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 |
376 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
343 | callback to be invoked whenever a signal occurs. |
377 | callback to be invoked whenever a signal occurs. |
344 | |
378 | |
345 | Although the callback might get passed parameters, their value and |
379 | Although the callback might get passed parameters, their value and |
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357 | |
391 | |
358 | This watcher might use %SIG (depending on the event loop used), so |
392 | This watcher might use %SIG (depending on the event loop used), so |
359 | programs overwriting those signals directly will likely not work |
393 | programs overwriting those signals directly will likely not work |
360 | correctly. |
394 | correctly. |
361 | |
395 | |
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396 | Example: exit on SIGINT |
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397 | |
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398 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
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399 | |
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400 | Restart Behaviour |
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401 | While restart behaviour is up to the event loop implementation, most |
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402 | will not restart syscalls (that includes Async::Interrupt and AnyEvent's |
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403 | pure perl implementation). |
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404 | |
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405 | Safe/Unsafe Signals |
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406 | Perl signals can be either "safe" (synchronous to opcode handling) or |
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407 | "unsafe" (asynchronous) - the former might get delayed indefinitely, the |
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408 | latter might corrupt your memory. |
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409 | |
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410 | AnyEvent signal handlers are, in addition, synchronous to the event |
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411 | loop, i.e. they will not interrupt your running perl program but will |
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412 | only be called as part of the normal event handling (just like timer, |
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413 | I/O etc. callbacks, too). |
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414 | |
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415 | Signal Races, Delays and Workarounds |
362 | Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not |
416 | 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 |
417 | 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, |
418 | 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 |
419 | 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: |
420 | 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 |
421 | in $AnyEvent::MAX_SIGNAL_LATENCY (default: 10 seconds). This variable |
368 | watcher is created, and should be left alone otherwise. Higher values |
422 | can be changed only before the first signal watcher is created, and |
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423 | should be left alone otherwise. This variable determines how often |
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424 | 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 |
425 | will cause fewer spurious wake-ups, which is better for power and CPU |
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426 | saving. |
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427 | |
370 | saving. All these problems can be avoided by installing the optional |
428 | All these problems can be avoided by installing the optional |
371 | Async::Interrupt module. |
429 | Async::Interrupt module, which works with most event loops. It will not |
372 | |
430 | work with inherently broken event loops such as Event or Event::Lib (and |
373 | Example: exit on SIGINT |
431 | not with POE currently, as POE does it's own workaround with one-second |
374 | |
432 | latency). For those, you just have to suffer the delays. |
375 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
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376 | |
433 | |
377 | CHILD PROCESS WATCHERS |
434 | CHILD PROCESS WATCHERS |
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435 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
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436 | |
378 | You can also watch on a child process exit and catch its exit status. |
437 | You can also watch on a child process exit and catch its exit status. |
379 | |
438 | |
380 | The child process is specified by the "pid" argument (if set to 0, it |
439 | The child process is specified by the "pid" argument (one some backends, |
381 | watches for any child process exit). The watcher will triggered only |
440 | 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 |
441 | The watcher will be triggered only when the child process has finished |
383 | on any trace events (stopped/continued). |
442 | and an exit status is available, not on any trace events |
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443 | (stopped/continued). |
384 | |
444 | |
385 | The callback will be called with the pid and exit status (as returned by |
445 | 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 |
446 | waitpid), so unlike other watcher types, you *can* rely on child watcher |
387 | callback arguments. |
447 | callback arguments. |
388 | |
448 | |
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427 | |
487 | |
428 | # do something else, then wait for process exit |
488 | # do something else, then wait for process exit |
429 | $done->recv; |
489 | $done->recv; |
430 | |
490 | |
431 | IDLE WATCHERS |
491 | IDLE WATCHERS |
432 | Sometimes there is a need to do something, but it is not so important to |
492 | $w = AnyEvent->idle (cb => <callback>); |
433 | do it instantly, but only when there is nothing better to do. This |
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434 | "nothing better to do" is usually defined to be "no other events need |
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435 | attention by the event loop". |
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436 | |
493 | |
437 | Idle watchers ideally get invoked when the event loop has nothing better |
494 | Repeatedly invoke the callback after the process becomes idle, until |
438 | to do, just before it would block the process to wait for new events. |
495 | either the watcher is destroyed or new events have been detected. |
439 | Instead of blocking, the idle watcher is invoked. |
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440 | |
496 | |
441 | Most event loops unfortunately do not really support idle watchers (only |
497 | Idle watchers are useful when there is a need to do something, but it is |
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498 | not so important (or wise) to do it instantly. The callback will be |
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499 | invoked only when there is "nothing better to do", which is usually |
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500 | defined as "all outstanding events have been handled and no new events |
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501 | have been detected". That means that idle watchers ideally get invoked |
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502 | when the event loop has just polled for new events but none have been |
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503 | detected. Instead of blocking to wait for more events, the idle watchers |
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504 | will be invoked. |
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505 | |
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506 | Unfortunately, most event loops do not really support idle watchers |
442 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
507 | (only EV, Event and Glib do it in a usable fashion) - for the rest, |
443 | will simply call the callback "from time to time". |
508 | AnyEvent will simply call the callback "from time to time". |
444 | |
509 | |
445 | Example: read lines from STDIN, but only process them when the program |
510 | Example: read lines from STDIN, but only process them when the program |
446 | is otherwise idle: |
511 | is otherwise idle: |
447 | |
512 | |
448 | my @lines; # read data |
513 | my @lines; # read data |
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461 | } |
526 | } |
462 | }); |
527 | }); |
463 | }); |
528 | }); |
464 | |
529 | |
465 | CONDITION VARIABLES |
530 | CONDITION VARIABLES |
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531 | $cv = AnyEvent->condvar; |
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532 | |
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533 | $cv->send (<list>); |
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534 | my @res = $cv->recv; |
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535 | |
466 | If you are familiar with some event loops you will know that all of them |
536 | 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 |
537 | require you to run some blocking "loop", "run" or similar function that |
468 | will actively watch for new events and call your callbacks. |
538 | will actively watch for new events and call your callbacks. |
469 | |
539 | |
470 | AnyEvent is slightly different: it expects somebody else to run the |
540 | AnyEvent is slightly different: it expects somebody else to run the |
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490 | Condition variables are similar to callbacks, except that you can |
560 | Condition variables are similar to callbacks, except that you can |
491 | optionally wait for them. They can also be called merge points - points |
561 | optionally wait for them. They can also be called merge points - points |
492 | in time where multiple outstanding events have been processed. And yet |
562 | in time where multiple outstanding events have been processed. And yet |
493 | another way to call them is transactions - each condition variable can |
563 | another way to call them is transactions - each condition variable can |
494 | be used to represent a transaction, which finishes at some point and |
564 | be used to represent a transaction, which finishes at some point and |
495 | delivers a result. |
565 | delivers a result. And yet some people know them as "futures" - a |
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566 | promise to compute/deliver something that you can wait for. |
496 | |
567 | |
497 | Condition variables are very useful to signal that something has |
568 | Condition variables are very useful to signal that something has |
498 | finished, for example, if you write a module that does asynchronous http |
569 | finished, for example, if you write a module that does asynchronous http |
499 | requests, then a condition variable would be the ideal candidate to |
570 | requests, then a condition variable would be the ideal candidate to |
500 | signal the availability of results. The user can either act when the |
571 | signal the availability of results. The user can either act when the |
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521 | which eventually calls "-> send", and the "consumer side", which waits |
592 | which eventually calls "-> send", and the "consumer side", which waits |
522 | for the send to occur. |
593 | for the send to occur. |
523 | |
594 | |
524 | Example: wait for a timer. |
595 | Example: wait for a timer. |
525 | |
596 | |
526 | # wait till the result is ready |
597 | # condition: "wait till the timer is fired" |
527 | my $result_ready = AnyEvent->condvar; |
598 | my $timer_fired = AnyEvent->condvar; |
528 | |
599 | |
529 | # do something such as adding a timer |
600 | # create the timer - we could wait for, say |
530 | # or socket watcher the calls $result_ready->send |
601 | # a handle becomign ready, or even an |
531 | # when the "result" is ready. |
602 | # AnyEvent::HTTP request to finish, but |
532 | # in this case, we simply use a timer: |
603 | # in this case, we simply use a timer: |
533 | my $w = AnyEvent->timer ( |
604 | my $w = AnyEvent->timer ( |
534 | after => 1, |
605 | after => 1, |
535 | cb => sub { $result_ready->send }, |
606 | cb => sub { $timer_fired->send }, |
536 | ); |
607 | ); |
537 | |
608 | |
538 | # this "blocks" (while handling events) till the callback |
609 | # this "blocks" (while handling events) till the callback |
539 | # calls -<send |
610 | # calls ->send |
540 | $result_ready->recv; |
611 | $timer_fired->recv; |
541 | |
612 | |
542 | Example: wait for a timer, but take advantage of the fact that condition |
613 | Example: wait for a timer, but take advantage of the fact that condition |
543 | variables are also callable directly. |
614 | variables are also callable directly. |
544 | |
615 | |
545 | my $done = AnyEvent->condvar; |
616 | my $done = AnyEvent->condvar; |
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601 | into one. For example, a function that pings many hosts in parallel |
672 | into one. For example, a function that pings many hosts in parallel |
602 | might want to use a condition variable for the whole process. |
673 | might want to use a condition variable for the whole process. |
603 | |
674 | |
604 | Every call to "->begin" will increment a counter, and every call to |
675 | Every call to "->begin" will increment a counter, and every call to |
605 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
676 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
606 | (last) callback passed to "begin" will be executed. That callback is |
677 | (last) callback passed to "begin" will be executed, passing the |
607 | *supposed* to call "->send", but that is not required. If no |
678 | condvar as first argument. That callback is *supposed* to call |
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679 | "->send", but that is not required. If no group callback was set, |
608 | callback was set, "send" will be called without any arguments. |
680 | "send" will be called without any arguments. |
609 | |
681 | |
610 | You can think of "$cv->send" giving you an OR condition (one call |
682 | You can think of "$cv->send" giving you an OR condition (one call |
611 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
683 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
612 | condition (all "begin" calls must be "end"'ed before the condvar |
684 | condition (all "begin" calls must be "end"'ed before the condvar |
613 | sends). |
685 | sends). |
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641 | that are begung can potentially be zero: |
713 | that are begung can potentially be zero: |
642 | |
714 | |
643 | my $cv = AnyEvent->condvar; |
715 | my $cv = AnyEvent->condvar; |
644 | |
716 | |
645 | my %result; |
717 | my %result; |
646 | $cv->begin (sub { $cv->send (\%result) }); |
718 | $cv->begin (sub { shift->send (\%result) }); |
647 | |
719 | |
648 | for my $host (@list_of_hosts) { |
720 | for my $host (@list_of_hosts) { |
649 | $cv->begin; |
721 | $cv->begin; |
650 | ping_host_then_call_callback $host, sub { |
722 | ping_host_then_call_callback $host, sub { |
651 | $result{$host} = ...; |
723 | $result{$host} = ...; |
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718 | |
790 | |
719 | $cb = $cv->cb ($cb->($cv)) |
791 | $cb = $cv->cb ($cb->($cv)) |
720 | This is a mutator function that returns the callback set and |
792 | This is a mutator function that returns the callback set and |
721 | optionally replaces it before doing so. |
793 | optionally replaces it before doing so. |
722 | |
794 | |
723 | The callback will be called when the condition becomes "true", i.e. |
795 | The callback will be called when the condition becomes (or already |
724 | when "send" or "croak" are called, with the only argument being the |
796 | was) "true", i.e. when "send" or "croak" are called (or were |
725 | condition variable itself. Calling "recv" inside the callback or at |
797 | called), with the only argument being the condition variable itself. |
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798 | Calling "recv" inside the callback or at any later time is |
726 | any later time is guaranteed not to block. |
799 | guaranteed not to block. |
727 | |
800 | |
728 | SUPPORTED EVENT LOOPS/BACKENDS |
801 | SUPPORTED EVENT LOOPS/BACKENDS |
729 | The available backend classes are (every class has its own manpage): |
802 | The available backend classes are (every class has its own manpage): |
730 | |
803 | |
731 | Backends that are autoprobed when no other event loop can be found. |
804 | 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 |
805 | 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, |
806 | 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, |
807 | pure-perl implementation, which is available everywhere as it comes |
735 | which is available everywhere as it comes with AnyEvent itself. |
808 | with AnyEvent itself. |
736 | |
809 | |
737 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
810 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
738 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
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739 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
811 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
740 | |
812 | |
741 | Backends that are transparently being picked up when they are used. |
813 | Backends that are transparently being picked up when they are used. |
742 | These will be used when they are currently loaded when the first |
814 | 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 |
815 | watcher is created, in which case it is assumed that the application |
744 | is using them. This means that AnyEvent will automatically pick the |
816 | is using them. This means that AnyEvent will automatically pick the |
745 | right backend when the main program loads an event module before |
817 | right backend when the main program loads an event module before |
746 | anything starts to create watchers. Nothing special needs to be done |
818 | anything starts to create watchers. Nothing special needs to be done |
747 | by the main program. |
819 | by the main program. |
748 | |
820 | |
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821 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
749 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
822 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
750 | AnyEvent::Impl::Tk based on Tk, very broken. |
823 | AnyEvent::Impl::Tk based on Tk, very broken. |
751 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
824 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
752 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
825 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
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826 | AnyEvent::Impl::Irssi used when running within irssi. |
753 | |
827 | |
754 | Backends with special needs. |
828 | Backends with special needs. |
755 | Qt requires the Qt::Application to be instantiated first, but will |
829 | Qt requires the Qt::Application to be instantiated first, but will |
756 | otherwise be picked up automatically. As long as the main program |
830 | otherwise be picked up automatically. As long as the main program |
757 | instantiates the application before any AnyEvent watchers are |
831 | instantiates the application before any AnyEvent watchers are |
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822 | creates and installs the global IO::AIO watcher in a "post_detect" |
896 | creates and installs the global IO::AIO watcher in a "post_detect" |
823 | block to avoid autodetecting the event module at load time. |
897 | block to avoid autodetecting the event module at load time. |
824 | |
898 | |
825 | If called in scalar or list context, then it creates and returns an |
899 | If called in scalar or list context, then it creates and returns an |
826 | object that automatically removes the callback again when it is |
900 | object that automatically removes the callback again when it is |
|
|
901 | destroyed (or "undef" when the hook was immediately executed). See |
827 | destroyed. See Coro::BDB for a case where this is useful. |
902 | AnyEvent::AIO for a case where this is useful. |
|
|
903 | |
|
|
904 | Example: Create a watcher for the IO::AIO module and store it in |
|
|
905 | $WATCHER. Only do so after the event loop is initialised, though. |
|
|
906 | |
|
|
907 | our WATCHER; |
|
|
908 | |
|
|
909 | my $guard = AnyEvent::post_detect { |
|
|
910 | $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); |
|
|
911 | }; |
|
|
912 | |
|
|
913 | # the ||= is important in case post_detect immediately runs the block, |
|
|
914 | # as to not clobber the newly-created watcher. assigning both watcher and |
|
|
915 | # post_detect guard to the same variable has the advantage of users being |
|
|
916 | # able to just C<undef $WATCHER> if the watcher causes them grief. |
|
|
917 | |
|
|
918 | $WATCHER ||= $guard; |
828 | |
919 | |
829 | @AnyEvent::post_detect |
920 | @AnyEvent::post_detect |
830 | If there are any code references in this array (you can "push" to it |
921 | 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 |
922 | before or after loading AnyEvent), then they will called directly |
832 | after the event loop has been chosen. |
923 | after the event loop has been chosen. |
… | |
… | |
834 | You should check $AnyEvent::MODEL before adding to this array, |
925 | You should check $AnyEvent::MODEL before adding to this array, |
835 | though: if it is defined then the event loop has already been |
926 | though: if it is defined then the event loop has already been |
836 | detected, and the array will be ignored. |
927 | detected, and the array will be ignored. |
837 | |
928 | |
838 | Best use "AnyEvent::post_detect { BLOCK }" when your application |
929 | Best use "AnyEvent::post_detect { BLOCK }" when your application |
839 | allows it,as it takes care of these details. |
930 | allows it, as it takes care of these details. |
840 | |
931 | |
841 | This variable is mainly useful for modules that can do something |
932 | This variable is mainly useful for modules that can do something |
842 | useful when AnyEvent is used and thus want to know when it is |
933 | useful when AnyEvent is used and thus want to know when it is |
843 | initialised, but do not need to even load it by default. This array |
934 | initialised, but do not need to even load it by default. This array |
844 | provides the means to hook into AnyEvent passively, without loading |
935 | provides the means to hook into AnyEvent passively, without loading |
845 | it. |
936 | it. |
|
|
937 | |
|
|
938 | Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used |
|
|
939 | together, you could put this into Coro (this is the actual code used |
|
|
940 | by Coro to accomplish this): |
|
|
941 | |
|
|
942 | if (defined $AnyEvent::MODEL) { |
|
|
943 | # AnyEvent already initialised, so load Coro::AnyEvent |
|
|
944 | require Coro::AnyEvent; |
|
|
945 | } else { |
|
|
946 | # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent |
|
|
947 | # as soon as it is |
|
|
948 | push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; |
|
|
949 | } |
846 | |
950 | |
847 | WHAT TO DO IN A MODULE |
951 | WHAT TO DO IN A MODULE |
848 | As a module author, you should "use AnyEvent" and call AnyEvent methods |
952 | As a module author, you should "use AnyEvent" and call AnyEvent methods |
849 | freely, but you should not load a specific event module or rely on it. |
953 | freely, but you should not load a specific event module or rely on it. |
850 | |
954 | |
… | |
… | |
971 | Event::ExecFlow |
1075 | Event::ExecFlow |
972 | High level API for event-based execution flow control. |
1076 | High level API for event-based execution flow control. |
973 | |
1077 | |
974 | Coro |
1078 | Coro |
975 | Has special support for AnyEvent via Coro::AnyEvent. |
1079 | Has special support for AnyEvent via Coro::AnyEvent. |
|
|
1080 | |
|
|
1081 | SIMPLIFIED AE API |
|
|
1082 | Starting with version 5.0, AnyEvent officially supports a second, much |
|
|
1083 | simpler, API that is designed to reduce the calling, typing and memory |
|
|
1084 | overhead by using function call syntax and a fixed number of parameters. |
|
|
1085 | |
|
|
1086 | See the AE manpage for details. |
976 | |
1087 | |
977 | ERROR AND EXCEPTION HANDLING |
1088 | ERROR AND EXCEPTION HANDLING |
978 | In general, AnyEvent does not do any error handling - it relies on the |
1089 | 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 |
1090 | caller to do that if required. The AnyEvent::Strict module (see also the |
980 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
1091 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
… | |
… | |
1159 | warn "read: $input\n"; # output what has been read |
1270 | warn "read: $input\n"; # output what has been read |
1160 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1271 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1161 | }, |
1272 | }, |
1162 | ); |
1273 | ); |
1163 | |
1274 | |
1164 | my $time_watcher; # can only be used once |
|
|
1165 | |
|
|
1166 | sub new_timer { |
|
|
1167 | $timer = AnyEvent->timer (after => 1, cb => sub { |
1275 | my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub { |
1168 | warn "timeout\n"; # print 'timeout' about every second |
1276 | warn "timeout\n"; # print 'timeout' at most every second |
1169 | &new_timer; # and restart the time |
|
|
1170 | }); |
|
|
1171 | } |
1277 | }); |
1172 | |
|
|
1173 | new_timer; # create first timer |
|
|
1174 | |
1278 | |
1175 | $cv->recv; # wait until user enters /^q/i |
1279 | $cv->recv; # wait until user enters /^q/i |
1176 | |
1280 | |
1177 | REAL-WORLD EXAMPLE |
1281 | REAL-WORLD EXAMPLE |
1178 | Consider the Net::FCP module. It features (among others) the following |
1282 | Consider the Net::FCP module. It features (among others) the following |
… | |
… | |
1250 | |
1354 | |
1251 | The actual code goes further and collects all errors ("die"s, |
1355 | The actual code goes further and collects all errors ("die"s, |
1252 | exceptions) that occurred during request processing. The "result" method |
1356 | exceptions) that occurred during request processing. The "result" method |
1253 | detects whether an exception as thrown (it is stored inside the $txn |
1357 | detects whether an exception as thrown (it is stored inside the $txn |
1254 | object) and just throws the exception, which means connection errors and |
1358 | object) and just throws the exception, which means connection errors and |
1255 | other problems get reported tot he code that tries to use the result, |
1359 | other problems get reported to the code that tries to use the result, |
1256 | not in a random callback. |
1360 | not in a random callback. |
1257 | |
1361 | |
1258 | All of this enables the following usage styles: |
1362 | All of this enables the following usage styles: |
1259 | |
1363 | |
1260 | 1. Blocking: |
1364 | 1. Blocking: |
… | |
… | |
1305 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1409 | 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, |
1410 | 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. |
1411 | which it is), lets them fire exactly once and destroys them again. |
1308 | |
1412 | |
1309 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1413 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1310 | distribution. |
1414 | distribution. It uses the AE interface, which makes a real difference |
|
|
1415 | for the EV and Perl backends only. |
1311 | |
1416 | |
1312 | Explanation of the columns |
1417 | Explanation of the columns |
1313 | *watcher* is the number of event watchers created/destroyed. Since |
1418 | *watcher* is the number of event watchers created/destroyed. Since |
1314 | different event models feature vastly different performances, each event |
1419 | different event models feature vastly different performances, each event |
1315 | loop was given a number of watchers so that overall runtime is |
1420 | 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 |
1439 | *destroy* is the time, in microseconds, that it takes to destroy a |
1335 | single watcher. |
1440 | single watcher. |
1336 | |
1441 | |
1337 | Results |
1442 | Results |
1338 | name watchers bytes create invoke destroy comment |
1443 | name watchers bytes create invoke destroy comment |
1339 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1444 | 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 |
1445 | 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 |
1446 | 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 |
1447 | 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 |
1448 | 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 |
1449 | 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 |
1450 | 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 |
1451 | 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 |
1452 | 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 |
1453 | 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 |
1454 | 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 |
1455 | POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select |
1351 | |
1456 | |
1352 | Discussion |
1457 | Discussion |
1353 | The benchmark does *not* measure scalability of the event loop very |
1458 | 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) |
1459 | 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 |
1460 | 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 |
1471 | 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 |
1472 | EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 |
1368 | CPU cycles with POE. |
1473 | CPU cycles with POE. |
1369 | |
1474 | |
1370 | "EV" is the sole leader regarding speed and memory use, which are both |
1475 | "EV" is the sole leader regarding speed and memory use, which are both |
1371 | maximal/minimal, respectively. Even when going through AnyEvent, it uses |
1476 | maximal/minimal, respectively. When using the AE API there is zero |
|
|
1477 | overhead (when going through the AnyEvent API create is about 5-6 times |
|
|
1478 | 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 |
1479 | any other event loop and is still faster than Event natively). |
1373 | natively. |
|
|
1374 | |
1480 | |
1375 | The pure perl implementation is hit in a few sweet spots (both the |
1481 | 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 |
1482 | constant timeout and the use of a single fd hit optimisations in the |
1377 | perl interpreter and the backend itself). Nevertheless this shows that |
1483 | perl interpreter and the backend itself). Nevertheless this shows that |
1378 | it adds very little overhead in itself. Like any select-based backend |
1484 | 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 |
1554 | 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 |
1555 | 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. |
1556 | many connections, most of which are idle at any one point in time. |
1451 | |
1557 | |
1452 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1558 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1453 | distribution. |
1559 | distribution. It uses the AE interface, which makes a real difference |
|
|
1560 | for the EV and Perl backends only. |
1454 | |
1561 | |
1455 | Explanation of the columns |
1562 | Explanation of the columns |
1456 | *sockets* is the number of sockets, and twice the number of "servers" |
1563 | *sockets* is the number of sockets, and twice the number of "servers" |
1457 | (as each server has a read and write socket end). |
1564 | (as each server has a read and write socket end). |
1458 | |
1565 | |
… | |
… | |
1464 | forwarding it to another server. This includes deleting the old timeout |
1571 | forwarding it to another server. This includes deleting the old timeout |
1465 | and creating a new one that moves the timeout into the future. |
1572 | and creating a new one that moves the timeout into the future. |
1466 | |
1573 | |
1467 | Results |
1574 | Results |
1468 | name sockets create request |
1575 | name sockets create request |
1469 | EV 20000 69.01 11.16 |
1576 | EV 20000 62.66 7.99 |
1470 | Perl 20000 73.32 35.87 |
1577 | Perl 20000 68.32 32.64 |
1471 | IOAsync 20000 157.00 98.14 epoll |
1578 | IOAsync 20000 174.06 101.15 epoll |
1472 | IOAsync 20000 159.31 616.06 poll |
1579 | IOAsync 20000 174.67 610.84 poll |
1473 | Event 20000 212.62 257.32 |
1580 | Event 20000 202.69 242.91 |
1474 | Glib 20000 651.16 1896.30 |
1581 | Glib 20000 557.01 1689.52 |
1475 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1582 | POE 20000 341.54 12086.32 uses POE::Loop::Event |
1476 | |
1583 | |
1477 | Discussion |
1584 | Discussion |
1478 | This benchmark *does* measure scalability and overall performance of the |
1585 | This benchmark *does* measure scalability and overall performance of the |
1479 | particular event loop. |
1586 | particular event loop. |
1480 | |
1587 | |
… | |
… | |
1593 | As you can see, the AnyEvent + EV combination even beats the |
1700 | As you can see, the AnyEvent + EV combination even beats the |
1594 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
1701 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
1595 | backend easily beats IO::Lambda and POE. |
1702 | backend easily beats IO::Lambda and POE. |
1596 | |
1703 | |
1597 | And even the 100% non-blocking version written using the high-level (and |
1704 | And even the 100% non-blocking version written using the high-level (and |
1598 | slow :) AnyEvent::Handle abstraction beats both POE and IO::Lambda by a |
1705 | slow :) AnyEvent::Handle abstraction beats both POE and IO::Lambda |
1599 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
1706 | higher level ("unoptimised") abstractions by a large margin, even though |
1600 | in a non-blocking way. |
1707 | it does all of DNS, tcp-connect and socket I/O in a non-blocking way. |
1601 | |
1708 | |
1602 | The two AnyEvent benchmarks programs can be found as eg/ae0.pl and |
1709 | The two AnyEvent benchmarks programs can be found as eg/ae0.pl and |
1603 | eg/ae2.pl in the AnyEvent distribution, the remaining benchmarks are |
1710 | eg/ae2.pl in the AnyEvent distribution, the remaining benchmarks are |
1604 | part of the IO::lambda distribution and were used without any changes. |
1711 | part of the IO::Lambda distribution and were used without any changes. |
1605 | |
1712 | |
1606 | SIGNALS |
1713 | SIGNALS |
1607 | AnyEvent currently installs handlers for these signals: |
1714 | AnyEvent currently installs handlers for these signals: |
1608 | |
1715 | |
1609 | SIGCHLD |
1716 | SIGCHLD |
… | |
… | |
1636 | it's built-in modules) are required to use it. |
1743 | it's built-in modules) are required to use it. |
1637 | |
1744 | |
1638 | That does not mean that AnyEvent won't take advantage of some additional |
1745 | That does not mean that AnyEvent won't take advantage of some additional |
1639 | modules if they are installed. |
1746 | modules if they are installed. |
1640 | |
1747 | |
1641 | This section epxlains which additional modules will be used, and how |
1748 | This section explains which additional modules will be used, and how |
1642 | they affect AnyEvent's operetion. |
1749 | they affect AnyEvent's operation. |
1643 | |
1750 | |
1644 | Async::Interrupt |
1751 | Async::Interrupt |
1645 | This slightly arcane module is used to implement fast signal |
1752 | This slightly arcane module is used to implement fast signal |
1646 | handling: To my knowledge, there is no way to do completely |
1753 | handling: To my knowledge, there is no way to do completely |
1647 | race-free and quick signal handling in pure perl. To ensure that |
1754 | race-free and quick signal handling in pure perl. To ensure that |
1648 | signals still get delivered, AnyEvent will start an interval timer |
1755 | signals still get delivered, AnyEvent will start an interval timer |
1649 | to wake up perl (and catch the signals) with soemd elay (default is |
1756 | to wake up perl (and catch the signals) with some delay (default is |
1650 | 10 seconds, look for $AnyEvent::MAX_SIGNAL_LATENCY). |
1757 | 10 seconds, look for $AnyEvent::MAX_SIGNAL_LATENCY). |
1651 | |
1758 | |
1652 | If this module is available, then it will be used to implement |
1759 | If this module is available, then it will be used to implement |
1653 | signal catching, which means that signals will not be delayed, and |
1760 | signal catching, which means that signals will not be delayed, and |
1654 | the event loop will not be interrupted regularly, which is more |
1761 | the event loop will not be interrupted regularly, which is more |
1655 | efficient (And good for battery life on laptops). |
1762 | efficient (and good for battery life on laptops). |
1656 | |
1763 | |
1657 | This affects not just the pure-perl event loop, but also other event |
1764 | 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). |
1765 | loops that have no signal handling on their own (e.g. Glib, Tk, Qt). |
|
|
1766 | |
|
|
1767 | Some event loops (POE, Event, Event::Lib) offer signal watchers |
|
|
1768 | natively, and either employ their own workarounds (POE) or use |
|
|
1769 | AnyEvent's workaround (using $AnyEvent::MAX_SIGNAL_LATENCY). |
|
|
1770 | Installing Async::Interrupt does nothing for those backends. |
1659 | |
1771 | |
1660 | EV This module isn't really "optional", as it is simply one of the |
1772 | 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 |
1773 | backend event loops that AnyEvent can use. However, it is simply the |
1662 | best event loop available in terms of features, speed and stability: |
1774 | best event loop available in terms of features, speed and stability: |
1663 | It supports the AnyEvent API optimally, implements all the watcher |
1775 | It supports the AnyEvent API optimally, implements all the watcher |
… | |
… | |
1665 | clock is available, can take avdantage of advanced kernel interfaces |
1777 | clock is available, can take avdantage of advanced kernel interfaces |
1666 | such as "epoll" and "kqueue", and is the fastest backend *by far*. |
1778 | such as "epoll" and "kqueue", and is the fastest backend *by far*. |
1667 | You can even embed Glib/Gtk2 in it (or vice versa, see EV::Glib and |
1779 | You can even embed Glib/Gtk2 in it (or vice versa, see EV::Glib and |
1668 | Glib::EV). |
1780 | Glib::EV). |
1669 | |
1781 | |
|
|
1782 | If you only use backends that rely on another event loop (e.g. |
|
|
1783 | "Tk"), then this module will do nothing for you. |
|
|
1784 | |
1670 | Guard |
1785 | Guard |
1671 | The guard module, when used, will be used to implement |
1786 | The guard module, when used, will be used to implement |
1672 | "AnyEvent::Util::guard". This speeds up guards considerably (and |
1787 | "AnyEvent::Util::guard". This speeds up guards considerably (and |
1673 | uses a lot less memory), but otherwise doesn't affect guard |
1788 | uses a lot less memory), but otherwise doesn't affect guard |
1674 | operation much. It is purely used for performance. |
1789 | operation much. It is purely used for performance. |
1675 | |
1790 | |
1676 | JSON and JSON::XS |
1791 | JSON and JSON::XS |
1677 | This module is required when you want to read or write JSON data via |
1792 | One of these modules is required when you want to read or write JSON |
1678 | AnyEvent::Handle. It is also written in pure-perl, but can take |
1793 | data via AnyEvent::Handle. JSON is also written in pure-perl, but |
1679 | advantage of the ulta-high-speed JSON::XS module when it is |
1794 | can take advantage of the ultra-high-speed JSON::XS module when it |
1680 | installed. |
1795 | is installed. |
1681 | |
|
|
1682 | In fact, AnyEvent::Handle will use JSON::XS by default if it is |
|
|
1683 | installed. |
|
|
1684 | |
1796 | |
1685 | Net::SSLeay |
1797 | Net::SSLeay |
1686 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
1798 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
1687 | worthwhile: If this module is installed, then AnyEvent::Handle (with |
1799 | worthwhile: If this module is installed, then AnyEvent::Handle (with |
1688 | the help of AnyEvent::TLS), gains the ability to do TLS/SSL. |
1800 | the help of AnyEvent::TLS), gains the ability to do TLS/SSL. |
… | |
… | |
1694 | additionally use it to try to use a monotonic clock for timing |
1806 | additionally use it to try to use a monotonic clock for timing |
1695 | stability. |
1807 | stability. |
1696 | |
1808 | |
1697 | FORK |
1809 | FORK |
1698 | Most event libraries are not fork-safe. The ones who are usually are |
1810 | Most event libraries are not fork-safe. The ones who are usually are |
1699 | because they rely on inefficient but fork-safe "select" or "poll" calls. |
1811 | because they rely on inefficient but fork-safe "select" or "poll" calls |
1700 | Only EV is fully fork-aware. |
1812 | - higher performance APIs such as BSD's kqueue or the dreaded Linux |
|
|
1813 | epoll are usually badly thought-out hacks that are incompatible with |
|
|
1814 | fork in one way or another. Only EV is fully fork-aware and ensures that |
|
|
1815 | you continue event-processing in both parent and child (or both, if you |
|
|
1816 | know what you are doing). |
|
|
1817 | |
|
|
1818 | This means that, in general, you cannot fork and do event processing in |
|
|
1819 | the child if the event library was initialised before the fork (which |
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|
1820 | usually happens when the first AnyEvent watcher is created, or the |
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|
1821 | library is loaded). |
1701 | |
1822 | |
1702 | If you have to fork, you must either do so *before* creating your first |
1823 | If you have to fork, you must either do so *before* creating your first |
1703 | watcher OR you must not use AnyEvent at all in the child OR you must do |
1824 | watcher OR you must not use AnyEvent at all in the child OR you must do |
1704 | something completely out of the scope of AnyEvent. |
1825 | something completely out of the scope of AnyEvent. |
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|
1826 | |
|
|
1827 | The problem of doing event processing in the parent *and* the child is |
|
|
1828 | much more complicated: even for backends that *are* fork-aware or |
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|
1829 | fork-safe, their behaviour is not usually what you want: fork clones all |
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|
1830 | watchers, that means all timers, I/O watchers etc. are active in both |
|
|
1831 | parent and child, which is almost never what you want. USing "exec" to |
|
|
1832 | start worker children from some kind of manage rprocess is usually |
|
|
1833 | preferred, because it is much easier and cleaner, at the expense of |
|
|
1834 | having to have another binary. |
1705 | |
1835 | |
1706 | SECURITY CONSIDERATIONS |
1836 | SECURITY CONSIDERATIONS |
1707 | AnyEvent can be forced to load any event model via |
1837 | AnyEvent can be forced to load any event model via |
1708 | $ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used |
1838 | $ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used |
1709 | to execute arbitrary code or directly gain access, it can easily be used |
1839 | to execute arbitrary code or directly gain access, it can easily be used |
… | |
… | |
1741 | Event::Lib, Qt, POE. |
1871 | Event::Lib, Qt, POE. |
1742 | |
1872 | |
1743 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1873 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1744 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1874 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1745 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE, |
1875 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE, |
1746 | AnyEvent::Impl::IOAsync. |
1876 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi. |
1747 | |
1877 | |
1748 | Non-blocking file handles, sockets, TCP clients and servers: |
1878 | Non-blocking file handles, sockets, TCP clients and servers: |
1749 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
1879 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
1750 | |
1880 | |
1751 | Asynchronous DNS: AnyEvent::DNS. |
1881 | Asynchronous DNS: AnyEvent::DNS. |