1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | AnyEvent - provide framework for multiple event loops |
3 | AnyEvent - provide framework for multiple event loops |
4 | |
4 | |
5 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops |
5 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported |
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6 | event loops. |
6 | |
7 | |
7 | =head1 SYNOPSIS |
8 | =head1 SYNOPSIS |
8 | |
9 | |
9 | use AnyEvent; |
10 | use AnyEvent; |
10 | |
11 | |
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12 | # file descriptor readable |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
13 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
12 | |
14 | |
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15 | # one-shot or repeating timers |
13 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
16 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
14 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
17 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
15 | |
18 | |
16 | print AnyEvent->now; # prints current event loop time |
19 | print AnyEvent->now; # prints current event loop time |
17 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
20 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
18 | |
21 | |
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22 | # POSIX signal |
19 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
23 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
20 | |
24 | |
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25 | # child process exit |
21 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
26 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
22 | my ($pid, $status) = @_; |
27 | my ($pid, $status) = @_; |
23 | ... |
28 | ... |
24 | }); |
29 | }); |
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30 | |
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31 | # called when event loop idle (if applicable) |
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32 | my $w = AnyEvent->idle (cb => sub { ... }); |
25 | |
33 | |
26 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
34 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
27 | $w->send; # wake up current and all future recv's |
35 | $w->send; # wake up current and all future recv's |
28 | $w->recv; # enters "main loop" till $condvar gets ->send |
36 | $w->recv; # enters "main loop" till $condvar gets ->send |
29 | # use a condvar in callback mode: |
37 | # use a condvar in callback mode: |
… | |
… | |
320 | In either case, if you care (and in most cases, you don't), then you |
328 | In either case, if you care (and in most cases, you don't), then you |
321 | can get whatever behaviour you want with any event loop, by taking the |
329 | can get whatever behaviour you want with any event loop, by taking the |
322 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
330 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
323 | account. |
331 | account. |
324 | |
332 | |
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333 | =item AnyEvent->now_update |
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334 | |
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335 | Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache |
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336 | the current time for each loop iteration (see the discussion of L<< |
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337 | AnyEvent->now >>, above). |
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338 | |
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339 | When a callback runs for a long time (or when the process sleeps), then |
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340 | this "current" time will differ substantially from the real time, which |
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341 | might affect timers and time-outs. |
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342 | |
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343 | When this is the case, you can call this method, which will update the |
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344 | event loop's idea of "current time". |
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345 | |
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346 | Note that updating the time I<might> cause some events to be handled. |
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347 | |
325 | =back |
348 | =back |
326 | |
349 | |
327 | =head2 SIGNAL WATCHERS |
350 | =head2 SIGNAL WATCHERS |
328 | |
351 | |
329 | You can watch for signals using a signal watcher, C<signal> is the signal |
352 | You can watch for signals using a signal watcher, C<signal> is the signal |
… | |
… | |
369 | |
392 | |
370 | There is a slight catch to child watchers, however: you usually start them |
393 | There is a slight catch to child watchers, however: you usually start them |
371 | I<after> the child process was created, and this means the process could |
394 | I<after> the child process was created, and this means the process could |
372 | have exited already (and no SIGCHLD will be sent anymore). |
395 | have exited already (and no SIGCHLD will be sent anymore). |
373 | |
396 | |
374 | Not all event models handle this correctly (POE doesn't), but even for |
397 | Not all event models handle this correctly (neither POE nor IO::Async do, |
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398 | see their AnyEvent::Impl manpages for details), but even for event models |
375 | event models that I<do> handle this correctly, they usually need to be |
399 | that I<do> handle this correctly, they usually need to be loaded before |
376 | loaded before the process exits (i.e. before you fork in the first place). |
400 | the process exits (i.e. before you fork in the first place). AnyEvent's |
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401 | pure perl event loop handles all cases correctly regardless of when you |
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402 | start the watcher. |
377 | |
403 | |
378 | This means you cannot create a child watcher as the very first thing in an |
404 | This means you cannot create a child watcher as the very first |
379 | AnyEvent program, you I<have> to create at least one watcher before you |
405 | thing in an AnyEvent program, you I<have> to create at least one |
380 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
406 | watcher before you C<fork> the child (alternatively, you can call |
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407 | C<AnyEvent::detect>). |
381 | |
408 | |
382 | Example: fork a process and wait for it |
409 | Example: fork a process and wait for it |
383 | |
410 | |
384 | my $done = AnyEvent->condvar; |
411 | my $done = AnyEvent->condvar; |
385 | |
412 | |
… | |
… | |
395 | ); |
422 | ); |
396 | |
423 | |
397 | # do something else, then wait for process exit |
424 | # do something else, then wait for process exit |
398 | $done->recv; |
425 | $done->recv; |
399 | |
426 | |
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427 | =head2 IDLE WATCHERS |
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428 | |
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429 | Sometimes there is a need to do something, but it is not so important |
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430 | to do it instantly, but only when there is nothing better to do. This |
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431 | "nothing better to do" is usually defined to be "no other events need |
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432 | attention by the event loop". |
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433 | |
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434 | Idle watchers ideally get invoked when the event loop has nothing |
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435 | better to do, just before it would block the process to wait for new |
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436 | events. Instead of blocking, the idle watcher is invoked. |
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437 | |
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438 | Most event loops unfortunately do not really support idle watchers (only |
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439 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
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440 | will simply call the callback "from time to time". |
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441 | |
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442 | Example: read lines from STDIN, but only process them when the |
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443 | program is otherwise idle: |
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444 | |
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445 | my @lines; # read data |
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446 | my $idle_w; |
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447 | my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
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448 | push @lines, scalar <STDIN>; |
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449 | |
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450 | # start an idle watcher, if not already done |
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451 | $idle_w ||= AnyEvent->idle (cb => sub { |
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452 | # handle only one line, when there are lines left |
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453 | if (my $line = shift @lines) { |
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454 | print "handled when idle: $line"; |
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455 | } else { |
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456 | # otherwise disable the idle watcher again |
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457 | undef $idle_w; |
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458 | } |
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459 | }); |
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460 | }); |
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461 | |
400 | =head2 CONDITION VARIABLES |
462 | =head2 CONDITION VARIABLES |
401 | |
463 | |
402 | If you are familiar with some event loops you will know that all of them |
464 | If you are familiar with some event loops you will know that all of them |
403 | require you to run some blocking "loop", "run" or similar function that |
465 | require you to run some blocking "loop", "run" or similar function that |
404 | will actively watch for new events and call your callbacks. |
466 | will actively watch for new events and call your callbacks. |
… | |
… | |
537 | |
599 | |
538 | =item $cv->begin ([group callback]) |
600 | =item $cv->begin ([group callback]) |
539 | |
601 | |
540 | =item $cv->end |
602 | =item $cv->end |
541 | |
603 | |
542 | These two methods are EXPERIMENTAL and MIGHT CHANGE. |
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543 | |
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544 | These two methods can be used to combine many transactions/events into |
604 | These two methods can be used to combine many transactions/events into |
545 | one. For example, a function that pings many hosts in parallel might want |
605 | one. For example, a function that pings many hosts in parallel might want |
546 | to use a condition variable for the whole process. |
606 | to use a condition variable for the whole process. |
547 | |
607 | |
548 | Every call to C<< ->begin >> will increment a counter, and every call to |
608 | Every call to C<< ->begin >> will increment a counter, and every call to |
549 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
609 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
550 | >>, the (last) callback passed to C<begin> will be executed. That callback |
610 | >>, the (last) callback passed to C<begin> will be executed. That callback |
551 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
611 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
552 | callback was set, C<send> will be called without any arguments. |
612 | callback was set, C<send> will be called without any arguments. |
553 | |
613 | |
554 | Let's clarify this with the ping example: |
614 | You can think of C<< $cv->send >> giving you an OR condition (one call |
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615 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
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616 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
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617 | |
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618 | Let's start with a simple example: you have two I/O watchers (for example, |
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619 | STDOUT and STDERR for a program), and you want to wait for both streams to |
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620 | close before activating a condvar: |
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621 | |
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622 | my $cv = AnyEvent->condvar; |
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623 | |
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624 | $cv->begin; # first watcher |
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625 | my $w1 = AnyEvent->io (fh => $fh1, cb => sub { |
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626 | defined sysread $fh1, my $buf, 4096 |
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627 | or $cv->end; |
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628 | }); |
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629 | |
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630 | $cv->begin; # second watcher |
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631 | my $w2 = AnyEvent->io (fh => $fh2, cb => sub { |
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632 | defined sysread $fh2, my $buf, 4096 |
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633 | or $cv->end; |
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634 | }); |
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635 | |
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636 | $cv->recv; |
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637 | |
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638 | This works because for every event source (EOF on file handle), there is |
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639 | one call to C<begin>, so the condvar waits for all calls to C<end> before |
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640 | sending. |
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641 | |
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642 | The ping example mentioned above is slightly more complicated, as the |
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643 | there are results to be passwd back, and the number of tasks that are |
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644 | begung can potentially be zero: |
555 | |
645 | |
556 | my $cv = AnyEvent->condvar; |
646 | my $cv = AnyEvent->condvar; |
557 | |
647 | |
558 | my %result; |
648 | my %result; |
559 | $cv->begin (sub { $cv->send (\%result) }); |
649 | $cv->begin (sub { $cv->send (\%result) }); |
… | |
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579 | loop, which serves two important purposes: first, it sets the callback |
669 | loop, which serves two important purposes: first, it sets the callback |
580 | to be called once the counter reaches C<0>, and second, it ensures that |
670 | to be called once the counter reaches C<0>, and second, it ensures that |
581 | C<send> is called even when C<no> hosts are being pinged (the loop |
671 | C<send> is called even when C<no> hosts are being pinged (the loop |
582 | doesn't execute once). |
672 | doesn't execute once). |
583 | |
673 | |
584 | This is the general pattern when you "fan out" into multiple subrequests: |
674 | This is the general pattern when you "fan out" into multiple (but |
585 | use an outer C<begin>/C<end> pair to set the callback and ensure C<end> |
675 | potentially none) subrequests: use an outer C<begin>/C<end> pair to set |
586 | is called at least once, and then, for each subrequest you start, call |
676 | the callback and ensure C<end> is called at least once, and then, for each |
587 | C<begin> and for each subrequest you finish, call C<end>. |
677 | subrequest you start, call C<begin> and for each subrequest you finish, |
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678 | call C<end>. |
588 | |
679 | |
589 | =back |
680 | =back |
590 | |
681 | |
591 | =head3 METHODS FOR CONSUMERS |
682 | =head3 METHODS FOR CONSUMERS |
592 | |
683 | |
… | |
… | |
672 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
763 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
673 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
764 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
674 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
765 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
675 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
766 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
676 | |
767 | |
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768 | # warning, support for IO::Async is only partial, as it is too broken |
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769 | # and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async. |
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770 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs). |
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771 | |
677 | There is no support for WxWidgets, as WxWidgets has no support for |
772 | There is no support for WxWidgets, as WxWidgets has no support for |
678 | watching file handles. However, you can use WxWidgets through the |
773 | watching file handles. However, you can use WxWidgets through the |
679 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
774 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
680 | second, which was considered to be too horrible to even consider for |
775 | second, which was considered to be too horrible to even consider for |
681 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by using |
776 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by using |
… | |
… | |
873 | no warnings; |
968 | no warnings; |
874 | use strict qw(vars subs); |
969 | use strict qw(vars subs); |
875 | |
970 | |
876 | use Carp; |
971 | use Carp; |
877 | |
972 | |
878 | our $VERSION = 4.35; |
973 | our $VERSION = 4.8; |
879 | our $MODEL; |
974 | our $MODEL; |
880 | |
975 | |
881 | our $AUTOLOAD; |
976 | our $AUTOLOAD; |
882 | our @ISA; |
977 | our @ISA; |
883 | |
978 | |
884 | our @REGISTRY; |
979 | our @REGISTRY; |
885 | |
980 | |
886 | our $WIN32; |
981 | our $WIN32; |
887 | |
982 | |
888 | BEGIN { |
983 | BEGIN { |
889 | my $win32 = ! ! ($^O =~ /mswin32/i); |
984 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
890 | eval "sub WIN32(){ $win32 }"; |
985 | eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; |
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986 | |
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987 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
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988 | if ${^TAINT}; |
891 | } |
989 | } |
892 | |
990 | |
893 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
991 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
894 | |
992 | |
895 | our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred |
993 | our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred |
… | |
… | |
913 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
1011 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
914 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1012 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
915 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1013 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
916 | [Wx:: => AnyEvent::Impl::POE::], |
1014 | [Wx:: => AnyEvent::Impl::POE::], |
917 | [Prima:: => AnyEvent::Impl::POE::], |
1015 | [Prima:: => AnyEvent::Impl::POE::], |
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1016 | # IO::Async is just too broken - we would need workaorunds for its |
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1017 | # byzantine signal and broken child handling, among others. |
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1018 | # IO::Async is rather hard to detect, as it doesn't have any |
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1019 | # obvious default class. |
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1020 | # [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
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1021 | # [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
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1022 | # [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program |
918 | ); |
1023 | ); |
919 | |
1024 | |
920 | our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY); |
1025 | our %method = map +($_ => 1), |
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1026 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
921 | |
1027 | |
922 | our @post_detect; |
1028 | our @post_detect; |
923 | |
1029 | |
924 | sub post_detect(&) { |
1030 | sub post_detect(&) { |
925 | my ($cb) = @_; |
1031 | my ($cb) = @_; |
… | |
… | |
930 | 1 |
1036 | 1 |
931 | } else { |
1037 | } else { |
932 | push @post_detect, $cb; |
1038 | push @post_detect, $cb; |
933 | |
1039 | |
934 | defined wantarray |
1040 | defined wantarray |
935 | ? bless \$cb, "AnyEvent::Util::PostDetect" |
1041 | ? bless \$cb, "AnyEvent::Util::postdetect" |
936 | : () |
1042 | : () |
937 | } |
1043 | } |
938 | } |
1044 | } |
939 | |
1045 | |
940 | sub AnyEvent::Util::PostDetect::DESTROY { |
1046 | sub AnyEvent::Util::postdetect::DESTROY { |
941 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1047 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
942 | } |
1048 | } |
943 | |
1049 | |
944 | sub detect() { |
1050 | sub detect() { |
945 | unless ($MODEL) { |
1051 | unless ($MODEL) { |
… | |
… | |
982 | last; |
1088 | last; |
983 | } |
1089 | } |
984 | } |
1090 | } |
985 | |
1091 | |
986 | $MODEL |
1092 | $MODEL |
987 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
1093 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
988 | } |
1094 | } |
989 | } |
1095 | } |
990 | |
1096 | |
991 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
1097 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
992 | |
1098 | |
… | |
… | |
1013 | } |
1119 | } |
1014 | |
1120 | |
1015 | # utility function to dup a filehandle. this is used by many backends |
1121 | # utility function to dup a filehandle. this is used by many backends |
1016 | # to support binding more than one watcher per filehandle (they usually |
1122 | # to support binding more than one watcher per filehandle (they usually |
1017 | # allow only one watcher per fd, so we dup it to get a different one). |
1123 | # allow only one watcher per fd, so we dup it to get a different one). |
1018 | sub _dupfh($$$$) { |
1124 | sub _dupfh($$;$$) { |
1019 | my ($poll, $fh, $r, $w) = @_; |
1125 | my ($poll, $fh, $r, $w) = @_; |
1020 | |
1126 | |
1021 | # cygwin requires the fh mode to be matching, unix doesn't |
1127 | # cygwin requires the fh mode to be matching, unix doesn't |
1022 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1128 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1023 | : $poll eq "w" ? ($w, ">") |
1129 | : $poll eq "w" ? ($w, ">") |
1024 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1130 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1025 | |
1131 | |
1026 | open my $fh2, "$mode&" . fileno $fh |
1132 | open my $fh2, "$mode&" . fileno $fh |
1027 | or die "cannot dup() filehandle: $!"; |
1133 | or die "cannot dup() filehandle: $!,"; |
1028 | |
1134 | |
1029 | # we assume CLOEXEC is already set by perl in all important cases |
1135 | # we assume CLOEXEC is already set by perl in all important cases |
1030 | |
1136 | |
1031 | ($fh2, $rw) |
1137 | ($fh2, $rw) |
1032 | } |
1138 | } |
1033 | |
1139 | |
1034 | package AnyEvent::Base; |
1140 | package AnyEvent::Base; |
1035 | |
1141 | |
1036 | # default implementation for now and time |
1142 | # default implementations for many methods |
1037 | |
1143 | |
1038 | BEGIN { |
1144 | BEGIN { |
1039 | if (eval "use Time::HiRes (); time (); 1") { |
1145 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1040 | *_time = \&Time::HiRes::time; |
1146 | *_time = \&Time::HiRes::time; |
1041 | # if (eval "use POSIX (); (POSIX::times())... |
1147 | # if (eval "use POSIX (); (POSIX::times())... |
1042 | } else { |
1148 | } else { |
1043 | *_time = sub { time }; # epic fail |
1149 | *_time = sub { time }; # epic fail |
1044 | } |
1150 | } |
1045 | } |
1151 | } |
1046 | |
1152 | |
1047 | sub time { _time } |
1153 | sub time { _time } |
1048 | sub now { _time } |
1154 | sub now { _time } |
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1155 | sub now_update { } |
1049 | |
1156 | |
1050 | # default implementation for ->condvar |
1157 | # default implementation for ->condvar |
1051 | |
1158 | |
1052 | sub condvar { |
1159 | sub condvar { |
1053 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1160 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
1054 | } |
1161 | } |
1055 | |
1162 | |
1056 | # default implementation for ->signal |
1163 | # default implementation for ->signal |
1057 | |
1164 | |
1058 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
1165 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
… | |
… | |
1082 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case |
1189 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case |
1083 | } else { |
1190 | } else { |
1084 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1191 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1085 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
1192 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
1086 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
1193 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
|
|
1194 | |
|
|
1195 | # not strictly required, as $^F is normally 2, but let's make sure... |
|
|
1196 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
|
|
1197 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
1087 | } |
1198 | } |
1088 | |
1199 | |
1089 | $SIGPIPE_R |
1200 | $SIGPIPE_R |
1090 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1201 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1091 | |
1202 | |
1092 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
|
|
1093 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
|
|
1094 | |
|
|
1095 | $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); |
1203 | $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); |
1096 | } |
1204 | } |
1097 | |
1205 | |
1098 | my $signal = uc $arg{signal} |
1206 | my $signal = uc $arg{signal} |
1099 | or Carp::croak "required option 'signal' is missing"; |
1207 | or Carp::croak "required option 'signal' is missing"; |
1100 | |
1208 | |
1101 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1209 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1102 | $SIG{$signal} ||= sub { |
1210 | $SIG{$signal} ||= sub { |
|
|
1211 | local $!; |
1103 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1212 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1104 | undef $SIG_EV{$signal}; |
1213 | undef $SIG_EV{$signal}; |
1105 | }; |
1214 | }; |
1106 | |
1215 | |
1107 | bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" |
1216 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
1108 | } |
1217 | } |
1109 | |
1218 | |
1110 | sub AnyEvent::Base::Signal::DESTROY { |
1219 | sub AnyEvent::Base::signal::DESTROY { |
1111 | my ($signal, $cb) = @{$_[0]}; |
1220 | my ($signal, $cb) = @{$_[0]}; |
1112 | |
1221 | |
1113 | delete $SIG_CB{$signal}{$cb}; |
1222 | delete $SIG_CB{$signal}{$cb}; |
1114 | |
1223 | |
|
|
1224 | # delete doesn't work with older perls - they then |
|
|
1225 | # print weird messages, or just unconditionally exit |
|
|
1226 | # instead of getting the default action. |
1115 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1227 | undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1116 | } |
1228 | } |
1117 | |
1229 | |
1118 | # default implementation for ->child |
1230 | # default implementation for ->child |
1119 | |
1231 | |
1120 | our %PID_CB; |
1232 | our %PID_CB; |
1121 | our $CHLD_W; |
1233 | our $CHLD_W; |
1122 | our $CHLD_DELAY_W; |
1234 | our $CHLD_DELAY_W; |
1123 | our $PID_IDLE; |
|
|
1124 | our $WNOHANG; |
1235 | our $WNOHANG; |
1125 | |
1236 | |
1126 | sub _child_wait { |
1237 | sub _sigchld { |
1127 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1238 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1128 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1239 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1129 | (values %{ $PID_CB{0} || {} }); |
1240 | (values %{ $PID_CB{0} || {} }); |
1130 | } |
1241 | } |
1131 | |
|
|
1132 | undef $PID_IDLE; |
|
|
1133 | } |
|
|
1134 | |
|
|
1135 | sub _sigchld { |
|
|
1136 | # make sure we deliver these changes "synchronous" with the event loop. |
|
|
1137 | $CHLD_DELAY_W ||= AnyEvent->timer (after => 0, cb => sub { |
|
|
1138 | undef $CHLD_DELAY_W; |
|
|
1139 | &_child_wait; |
|
|
1140 | }); |
|
|
1141 | } |
1242 | } |
1142 | |
1243 | |
1143 | sub child { |
1244 | sub child { |
1144 | my (undef, %arg) = @_; |
1245 | my (undef, %arg) = @_; |
1145 | |
1246 | |
1146 | defined (my $pid = $arg{pid} + 0) |
1247 | defined (my $pid = $arg{pid} + 0) |
1147 | or Carp::croak "required option 'pid' is missing"; |
1248 | or Carp::croak "required option 'pid' is missing"; |
1148 | |
1249 | |
1149 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1250 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1150 | |
1251 | |
1151 | unless ($WNOHANG) { |
|
|
1152 | $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1252 | $WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1153 | } |
|
|
1154 | |
1253 | |
1155 | unless ($CHLD_W) { |
1254 | unless ($CHLD_W) { |
1156 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1255 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1157 | # child could be a zombie already, so make at least one round |
1256 | # child could be a zombie already, so make at least one round |
1158 | &_sigchld; |
1257 | &_sigchld; |
1159 | } |
1258 | } |
1160 | |
1259 | |
1161 | bless [$pid, $arg{cb}], "AnyEvent::Base::Child" |
1260 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1162 | } |
1261 | } |
1163 | |
1262 | |
1164 | sub AnyEvent::Base::Child::DESTROY { |
1263 | sub AnyEvent::Base::child::DESTROY { |
1165 | my ($pid, $cb) = @{$_[0]}; |
1264 | my ($pid, $cb) = @{$_[0]}; |
1166 | |
1265 | |
1167 | delete $PID_CB{$pid}{$cb}; |
1266 | delete $PID_CB{$pid}{$cb}; |
1168 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1267 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1169 | |
1268 | |
1170 | undef $CHLD_W unless keys %PID_CB; |
1269 | undef $CHLD_W unless keys %PID_CB; |
|
|
1270 | } |
|
|
1271 | |
|
|
1272 | # idle emulation is done by simply using a timer, regardless |
|
|
1273 | # of whether the process is idle or not, and not letting |
|
|
1274 | # the callback use more than 50% of the time. |
|
|
1275 | sub idle { |
|
|
1276 | my (undef, %arg) = @_; |
|
|
1277 | |
|
|
1278 | my ($cb, $w, $rcb) = $arg{cb}; |
|
|
1279 | |
|
|
1280 | $rcb = sub { |
|
|
1281 | if ($cb) { |
|
|
1282 | $w = _time; |
|
|
1283 | &$cb; |
|
|
1284 | $w = _time - $w; |
|
|
1285 | |
|
|
1286 | # never use more then 50% of the time for the idle watcher, |
|
|
1287 | # within some limits |
|
|
1288 | $w = 0.0001 if $w < 0.0001; |
|
|
1289 | $w = 5 if $w > 5; |
|
|
1290 | |
|
|
1291 | $w = AnyEvent->timer (after => $w, cb => $rcb); |
|
|
1292 | } else { |
|
|
1293 | # clean up... |
|
|
1294 | undef $w; |
|
|
1295 | undef $rcb; |
|
|
1296 | } |
|
|
1297 | }; |
|
|
1298 | |
|
|
1299 | $w = AnyEvent->timer (after => 0.05, cb => $rcb); |
|
|
1300 | |
|
|
1301 | bless \\$cb, "AnyEvent::Base::idle" |
|
|
1302 | } |
|
|
1303 | |
|
|
1304 | sub AnyEvent::Base::idle::DESTROY { |
|
|
1305 | undef $${$_[0]}; |
1171 | } |
1306 | } |
1172 | |
1307 | |
1173 | package AnyEvent::CondVar; |
1308 | package AnyEvent::CondVar; |
1174 | |
1309 | |
1175 | our @ISA = AnyEvent::CondVar::Base::; |
1310 | our @ISA = AnyEvent::CondVar::Base::; |
… | |
… | |
1249 | so on. |
1384 | so on. |
1250 | |
1385 | |
1251 | =head1 ENVIRONMENT VARIABLES |
1386 | =head1 ENVIRONMENT VARIABLES |
1252 | |
1387 | |
1253 | The following environment variables are used by this module or its |
1388 | The following environment variables are used by this module or its |
1254 | submodules: |
1389 | submodules. |
|
|
1390 | |
|
|
1391 | Note that AnyEvent will remove I<all> environment variables starting with |
|
|
1392 | C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is |
|
|
1393 | enabled. |
1255 | |
1394 | |
1256 | =over 4 |
1395 | =over 4 |
1257 | |
1396 | |
1258 | =item C<PERL_ANYEVENT_VERBOSE> |
1397 | =item C<PERL_ANYEVENT_VERBOSE> |
1259 | |
1398 | |
… | |
… | |
1271 | =item C<PERL_ANYEVENT_STRICT> |
1410 | =item C<PERL_ANYEVENT_STRICT> |
1272 | |
1411 | |
1273 | AnyEvent does not do much argument checking by default, as thorough |
1412 | AnyEvent does not do much argument checking by default, as thorough |
1274 | argument checking is very costly. Setting this variable to a true value |
1413 | argument checking is very costly. Setting this variable to a true value |
1275 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
1414 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
1276 | check the arguments passed to most method calls. If it finds any problems |
1415 | check the arguments passed to most method calls. If it finds any problems, |
1277 | it will croak. |
1416 | it will croak. |
1278 | |
1417 | |
1279 | In other words, enables "strict" mode. |
1418 | In other words, enables "strict" mode. |
1280 | |
1419 | |
1281 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
1420 | Unlike C<use strict>, it is definitely recommended to keep it off in |
1282 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
1421 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
1283 | developing programs can be very useful, however. |
1422 | developing programs can be very useful, however. |
1284 | |
1423 | |
1285 | =item C<PERL_ANYEVENT_MODEL> |
1424 | =item C<PERL_ANYEVENT_MODEL> |
1286 | |
1425 | |
… | |
… | |
1331 | |
1470 | |
1332 | =item C<PERL_ANYEVENT_MAX_FORKS> |
1471 | =item C<PERL_ANYEVENT_MAX_FORKS> |
1333 | |
1472 | |
1334 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
1473 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
1335 | will create in parallel. |
1474 | will create in parallel. |
|
|
1475 | |
|
|
1476 | =item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS> |
|
|
1477 | |
|
|
1478 | The default value for the C<max_outstanding> parameter for the default DNS |
|
|
1479 | resolver - this is the maximum number of parallel DNS requests that are |
|
|
1480 | sent to the DNS server. |
|
|
1481 | |
|
|
1482 | =item C<PERL_ANYEVENT_RESOLV_CONF> |
|
|
1483 | |
|
|
1484 | The file to use instead of F</etc/resolv.conf> (or OS-specific |
|
|
1485 | configuration) in the default resolver. When set to the empty string, no |
|
|
1486 | default config will be used. |
1336 | |
1487 | |
1337 | =back |
1488 | =back |
1338 | |
1489 | |
1339 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1490 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1340 | |
1491 | |
… | |
… | |
1585 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1736 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1586 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1737 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1587 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1738 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1588 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1739 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1589 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1740 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
|
|
1741 | IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll |
|
|
1742 | IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll |
1590 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1743 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1591 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1744 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1592 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1745 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1593 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1746 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1594 | |
1747 | |
… | |
… | |
1623 | performance becomes really bad with lots of file descriptors (and few of |
1776 | performance becomes really bad with lots of file descriptors (and few of |
1624 | them active), of course, but this was not subject of this benchmark. |
1777 | them active), of course, but this was not subject of this benchmark. |
1625 | |
1778 | |
1626 | The C<Event> module has a relatively high setup and callback invocation |
1779 | The C<Event> module has a relatively high setup and callback invocation |
1627 | cost, but overall scores in on the third place. |
1780 | cost, but overall scores in on the third place. |
|
|
1781 | |
|
|
1782 | C<IO::Async> performs admirably well, about on par with C<Event>, even |
|
|
1783 | when using its pure perl backend. |
1628 | |
1784 | |
1629 | C<Glib>'s memory usage is quite a bit higher, but it features a |
1785 | C<Glib>'s memory usage is quite a bit higher, but it features a |
1630 | faster callback invocation and overall ends up in the same class as |
1786 | faster callback invocation and overall ends up in the same class as |
1631 | C<Event>. However, Glib scales extremely badly, doubling the number of |
1787 | C<Event>. However, Glib scales extremely badly, doubling the number of |
1632 | watchers increases the processing time by more than a factor of four, |
1788 | watchers increases the processing time by more than a factor of four, |
… | |
… | |
1710 | it to another server. This includes deleting the old timeout and creating |
1866 | it to another server. This includes deleting the old timeout and creating |
1711 | a new one that moves the timeout into the future. |
1867 | a new one that moves the timeout into the future. |
1712 | |
1868 | |
1713 | =head3 Results |
1869 | =head3 Results |
1714 | |
1870 | |
1715 | name sockets create request |
1871 | name sockets create request |
1716 | EV 20000 69.01 11.16 |
1872 | EV 20000 69.01 11.16 |
1717 | Perl 20000 73.32 35.87 |
1873 | Perl 20000 73.32 35.87 |
|
|
1874 | IOAsync 20000 157.00 98.14 epoll |
|
|
1875 | IOAsync 20000 159.31 616.06 poll |
1718 | Event 20000 212.62 257.32 |
1876 | Event 20000 212.62 257.32 |
1719 | Glib 20000 651.16 1896.30 |
1877 | Glib 20000 651.16 1896.30 |
1720 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1878 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1721 | |
1879 | |
1722 | =head3 Discussion |
1880 | =head3 Discussion |
1723 | |
1881 | |
1724 | This benchmark I<does> measure scalability and overall performance of the |
1882 | This benchmark I<does> measure scalability and overall performance of the |
1725 | particular event loop. |
1883 | particular event loop. |
… | |
… | |
1727 | EV is again fastest. Since it is using epoll on my system, the setup time |
1885 | EV is again fastest. Since it is using epoll on my system, the setup time |
1728 | is relatively high, though. |
1886 | is relatively high, though. |
1729 | |
1887 | |
1730 | Perl surprisingly comes second. It is much faster than the C-based event |
1888 | Perl surprisingly comes second. It is much faster than the C-based event |
1731 | loops Event and Glib. |
1889 | loops Event and Glib. |
|
|
1890 | |
|
|
1891 | IO::Async performs very well when using its epoll backend, and still quite |
|
|
1892 | good compared to Glib when using its pure perl backend. |
1732 | |
1893 | |
1733 | Event suffers from high setup time as well (look at its code and you will |
1894 | Event suffers from high setup time as well (look at its code and you will |
1734 | understand why). Callback invocation also has a high overhead compared to |
1895 | understand why). Callback invocation also has a high overhead compared to |
1735 | the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event |
1896 | the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event |
1736 | uses select or poll in basically all documented configurations. |
1897 | uses select or poll in basically all documented configurations. |
… | |
… | |
1799 | =item * C-based event loops perform very well with small number of |
1960 | =item * C-based event loops perform very well with small number of |
1800 | watchers, as the management overhead dominates. |
1961 | watchers, as the management overhead dominates. |
1801 | |
1962 | |
1802 | =back |
1963 | =back |
1803 | |
1964 | |
|
|
1965 | =head2 THE IO::Lambda BENCHMARK |
|
|
1966 | |
|
|
1967 | Recently I was told about the benchmark in the IO::Lambda manpage, which |
|
|
1968 | could be misinterpreted to make AnyEvent look bad. In fact, the benchmark |
|
|
1969 | simply compares IO::Lambda with POE, and IO::Lambda looks better (which |
|
|
1970 | shouldn't come as a surprise to anybody). As such, the benchmark is |
|
|
1971 | fine, and mostly shows that the AnyEvent backend from IO::Lambda isn't |
|
|
1972 | very optimal. But how would AnyEvent compare when used without the extra |
|
|
1973 | baggage? To explore this, I wrote the equivalent benchmark for AnyEvent. |
|
|
1974 | |
|
|
1975 | The benchmark itself creates an echo-server, and then, for 500 times, |
|
|
1976 | connects to the echo server, sends a line, waits for the reply, and then |
|
|
1977 | creates the next connection. This is a rather bad benchmark, as it doesn't |
|
|
1978 | test the efficiency of the framework or much non-blocking I/O, but it is a |
|
|
1979 | benchmark nevertheless. |
|
|
1980 | |
|
|
1981 | name runtime |
|
|
1982 | Lambda/select 0.330 sec |
|
|
1983 | + optimized 0.122 sec |
|
|
1984 | Lambda/AnyEvent 0.327 sec |
|
|
1985 | + optimized 0.138 sec |
|
|
1986 | Raw sockets/select 0.077 sec |
|
|
1987 | POE/select, components 0.662 sec |
|
|
1988 | POE/select, raw sockets 0.226 sec |
|
|
1989 | POE/select, optimized 0.404 sec |
|
|
1990 | |
|
|
1991 | AnyEvent/select/nb 0.085 sec |
|
|
1992 | AnyEvent/EV/nb 0.068 sec |
|
|
1993 | +state machine 0.134 sec |
|
|
1994 | |
|
|
1995 | The benchmark is also a bit unfair (my fault): the IO::Lambda/POE |
|
|
1996 | benchmarks actually make blocking connects and use 100% blocking I/O, |
|
|
1997 | defeating the purpose of an event-based solution. All of the newly |
|
|
1998 | written AnyEvent benchmarks use 100% non-blocking connects (using |
|
|
1999 | AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS |
|
|
2000 | resolver), so AnyEvent is at a disadvantage here, as non-blocking connects |
|
|
2001 | generally require a lot more bookkeeping and event handling than blocking |
|
|
2002 | connects (which involve a single syscall only). |
|
|
2003 | |
|
|
2004 | The last AnyEvent benchmark additionally uses L<AnyEvent::Handle>, which |
|
|
2005 | offers similar expressive power as POE and IO::Lambda, using conventional |
|
|
2006 | Perl syntax. This means that both the echo server and the client are 100% |
|
|
2007 | non-blocking, further placing it at a disadvantage. |
|
|
2008 | |
|
|
2009 | As you can see, the AnyEvent + EV combination even beats the |
|
|
2010 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
|
|
2011 | backend easily beats IO::Lambda and POE. |
|
|
2012 | |
|
|
2013 | And even the 100% non-blocking version written using the high-level (and |
|
|
2014 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a |
|
|
2015 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
|
|
2016 | in a non-blocking way. |
|
|
2017 | |
|
|
2018 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
|
|
2019 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
|
|
2020 | part of the IO::lambda distribution and were used without any changes. |
|
|
2021 | |
1804 | |
2022 | |
1805 | =head1 SIGNALS |
2023 | =head1 SIGNALS |
1806 | |
2024 | |
1807 | AnyEvent currently installs handlers for these signals: |
2025 | AnyEvent currently installs handlers for these signals: |
1808 | |
2026 | |
… | |
… | |
1811 | =item SIGCHLD |
2029 | =item SIGCHLD |
1812 | |
2030 | |
1813 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
2031 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
1814 | emulation for event loops that do not support them natively. Also, some |
2032 | emulation for event loops that do not support them natively. Also, some |
1815 | event loops install a similar handler. |
2033 | event loops install a similar handler. |
|
|
2034 | |
|
|
2035 | If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will |
|
|
2036 | reset it to default, to avoid losing child exit statuses. |
1816 | |
2037 | |
1817 | =item SIGPIPE |
2038 | =item SIGPIPE |
1818 | |
2039 | |
1819 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
2040 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
1820 | when AnyEvent gets loaded. |
2041 | when AnyEvent gets loaded. |
… | |
… | |
1832 | |
2053 | |
1833 | =back |
2054 | =back |
1834 | |
2055 | |
1835 | =cut |
2056 | =cut |
1836 | |
2057 | |
|
|
2058 | undef $SIG{CHLD} |
|
|
2059 | if $SIG{CHLD} eq 'IGNORE'; |
|
|
2060 | |
1837 | $SIG{PIPE} = sub { } |
2061 | $SIG{PIPE} = sub { } |
1838 | unless defined $SIG{PIPE}; |
2062 | unless defined $SIG{PIPE}; |
1839 | |
|
|
1840 | |
2063 | |
1841 | =head1 FORK |
2064 | =head1 FORK |
1842 | |
2065 | |
1843 | Most event libraries are not fork-safe. The ones who are usually are |
2066 | Most event libraries are not fork-safe. The ones who are usually are |
1844 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2067 | because they rely on inefficient but fork-safe C<select> or C<poll> |
… | |
… | |
1865 | use AnyEvent; |
2088 | use AnyEvent; |
1866 | |
2089 | |
1867 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
2090 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1868 | be used to probe what backend is used and gain other information (which is |
2091 | be used to probe what backend is used and gain other information (which is |
1869 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
2092 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
1870 | $ENV{PERL_ANYEGENT_STRICT}. |
2093 | $ENV{PERL_ANYEVENT_STRICT}. |
|
|
2094 | |
|
|
2095 | Note that AnyEvent will remove I<all> environment variables starting with |
|
|
2096 | C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is |
|
|
2097 | enabled. |
1871 | |
2098 | |
1872 | |
2099 | |
1873 | =head1 BUGS |
2100 | =head1 BUGS |
1874 | |
2101 | |
1875 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
2102 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |