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1=head1 NAME 1=head1 NAME
2 2
3AnyEvent - provide framework for multiple event loops 3AnyEvent - the DBI of event loop programming
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported 5EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6event loops. 6and POE are various supported event loops/environments.
7 7
8=head1 SYNOPSIS 8=head1 SYNOPSIS
9 9
10 use AnyEvent; 10 use AnyEvent;
11 11
40=head1 INTRODUCTION/TUTORIAL 40=head1 INTRODUCTION/TUTORIAL
41 41
42This manpage is mainly a reference manual. If you are interested 42This manpage is mainly a reference manual. If you are interested
43in a tutorial or some gentle introduction, have a look at the 43in a tutorial or some gentle introduction, have a look at the
44L<AnyEvent::Intro> manpage. 44L<AnyEvent::Intro> manpage.
45
46=head1 SUPPORT
47
48There is a mailinglist for discussing all things AnyEvent, and an IRC
49channel, too.
50
51See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
52Repository>, at L<http://anyevent.schmorp.de>, for more info.
45 53
46=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 54=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47 55
48Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 56Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49nowadays. So what is different about AnyEvent? 57nowadays. So what is different about AnyEvent?
173my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
174declared. 182declared.
175 183
176=head2 I/O WATCHERS 184=head2 I/O WATCHERS
177 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
178You can create an I/O watcher by calling the C<< AnyEvent->io >> method 192You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
180 194
181C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182for events (AnyEvent might or might not keep a reference to this file 196for events (AnyEvent might or might not keep a reference to this file
211 undef $w; 225 undef $w;
212 }); 226 });
213 227
214=head2 TIME WATCHERS 228=head2 TIME WATCHERS
215 229
230 $w = AnyEvent->timer (after => <seconds>, cb => <callback>);
231
232 $w = AnyEvent->timer (
233 after => <fractional_seconds>,
234 interval => <fractional_seconds>,
235 cb => <callback>,
236 );
237
216You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
217method with the following mandatory arguments: 239method with the following mandatory arguments:
218 240
219C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
220supported) the callback should be invoked. C<cb> is the callback to invoke 242supported) the callback should be invoked. C<cb> is the callback to invoke
341might affect timers and time-outs. 363might affect timers and time-outs.
342 364
343When this is the case, you can call this method, which will update the 365When this is the case, you can call this method, which will update the
344event loop's idea of "current time". 366event loop's idea of "current time".
345 367
368A typical example would be a script in a web server (e.g. C<mod_perl>) -
369when mod_perl executes the script, then the event loop will have the wrong
370idea about the "current time" (being potentially far in the past, when the
371script ran the last time). In that case you should arrange a call to C<<
372AnyEvent->now_update >> each time the web server process wakes up again
373(e.g. at the start of your script, or in a handler).
374
346Note that updating the time I<might> cause some events to be handled. 375Note that updating the time I<might> cause some events to be handled.
347 376
348=back 377=back
349 378
350=head2 SIGNAL WATCHERS 379=head2 SIGNAL WATCHERS
380
381 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
351 382
352You can watch for signals using a signal watcher, C<signal> is the signal 383You can watch for signals using a signal watcher, C<signal> is the signal
353I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl 384I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
354callback to be invoked whenever a signal occurs. 385callback to be invoked whenever a signal occurs.
355 386
368 399
369This watcher might use C<%SIG> (depending on the event loop used), 400This watcher might use C<%SIG> (depending on the event loop used),
370so programs overwriting those signals directly will likely not work 401so programs overwriting those signals directly will likely not work
371correctly. 402correctly.
372 403
404Example: exit on SIGINT
405
406 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
407
408=head3 Restart Behaviour
409
410While restart behaviour is up to the event loop implementation, most will
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation).
413
414=head3 Safe/Unsafe Signals
415
416Perl signals can be either "safe" (synchronous to opcode handling) or
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the
418latter might corrupt your memory.
419
420AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too).
424
425=head3 Signal Races, Delays and Workarounds
426
373Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not 427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
374support attaching callbacks to signals, which is a pity, as you cannot do 428callbacks to signals in a generic way, which is a pity, as you cannot
375race-free signal handling in perl. AnyEvent will try to do it's best, but 429do race-free signal handling in perl, requiring C libraries for
430this. AnyEvent will try to do it's best, which means in some cases,
376in some cases, signals will be delayed. The maximum time a signal might 431signals will be delayed. The maximum time a signal might be delayed is
377be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 432specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
378seconds). This variable can be changed only before the first signal 433variable can be changed only before the first signal watcher is created,
379watcher is created, and should be left alone otherwise. Higher values 434and should be left alone otherwise. This variable determines how often
435AnyEvent polls for signals (in case a wake-up was missed). Higher values
380will cause fewer spurious wake-ups, which is better for power and CPU 436will cause fewer spurious wake-ups, which is better for power and CPU
437saving.
438
381saving. All these problems can be avoided by installing the optional 439All these problems can be avoided by installing the optional
382L<Async::Interrupt> module. 440L<Async::Interrupt> module, which works with most event loops. It will not
383 441work with inherently broken event loops such as L<Event> or L<Event::Lib>
384Example: exit on SIGINT 442(and not with L<POE> currently, as POE does it's own workaround with
385 443one-second latency). For those, you just have to suffer the delays.
386 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
387 444
388=head2 CHILD PROCESS WATCHERS 445=head2 CHILD PROCESS WATCHERS
389 446
447 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
448
390You can also watch on a child process exit and catch its exit status. 449You can also watch on a child process exit and catch its exit status.
391 450
392The child process is specified by the C<pid> argument (if set to C<0>, it 451The child process is specified by the C<pid> argument (one some backends,
393watches for any child process exit). The watcher will triggered only when 452using C<0> watches for any child process exit, on others this will
394the child process has finished and an exit status is available, not on 453croak). The watcher will be triggered only when the child process has
395any trace events (stopped/continued). 454finished and an exit status is available, not on any trace events
455(stopped/continued).
396 456
397The callback will be called with the pid and exit status (as returned by 457The callback will be called with the pid and exit status (as returned by
398waitpid), so unlike other watcher types, you I<can> rely on child watcher 458waitpid), so unlike other watcher types, you I<can> rely on child watcher
399callback arguments. 459callback arguments.
400 460
441 # do something else, then wait for process exit 501 # do something else, then wait for process exit
442 $done->recv; 502 $done->recv;
443 503
444=head2 IDLE WATCHERS 504=head2 IDLE WATCHERS
445 505
506 $w = AnyEvent->idle (cb => <callback>);
507
446Sometimes there is a need to do something, but it is not so important 508Sometimes there is a need to do something, but it is not so important
447to do it instantly, but only when there is nothing better to do. This 509to do it instantly, but only when there is nothing better to do. This
448"nothing better to do" is usually defined to be "no other events need 510"nothing better to do" is usually defined to be "no other events need
449attention by the event loop". 511attention by the event loop".
450 512
476 }); 538 });
477 }); 539 });
478 540
479=head2 CONDITION VARIABLES 541=head2 CONDITION VARIABLES
480 542
543 $cv = AnyEvent->condvar;
544
545 $cv->send (<list>);
546 my @res = $cv->recv;
547
481If you are familiar with some event loops you will know that all of them 548If you are familiar with some event loops you will know that all of them
482require you to run some blocking "loop", "run" or similar function that 549require you to run some blocking "loop", "run" or similar function that
483will actively watch for new events and call your callbacks. 550will actively watch for new events and call your callbacks.
484 551
485AnyEvent is slightly different: it expects somebody else to run the event 552AnyEvent is slightly different: it expects somebody else to run the event
504Condition variables are similar to callbacks, except that you can 571Condition variables are similar to callbacks, except that you can
505optionally wait for them. They can also be called merge points - points 572optionally wait for them. They can also be called merge points - points
506in time where multiple outstanding events have been processed. And yet 573in time where multiple outstanding events have been processed. And yet
507another way to call them is transactions - each condition variable can be 574another way to call them is transactions - each condition variable can be
508used to represent a transaction, which finishes at some point and delivers 575used to represent a transaction, which finishes at some point and delivers
509a result. 576a result. And yet some people know them as "futures" - a promise to
577compute/deliver something that you can wait for.
510 578
511Condition variables are very useful to signal that something has finished, 579Condition variables are very useful to signal that something has finished,
512for example, if you write a module that does asynchronous http requests, 580for example, if you write a module that does asynchronous http requests,
513then a condition variable would be the ideal candidate to signal the 581then a condition variable would be the ideal candidate to signal the
514availability of results. The user can either act when the callback is 582availability of results. The user can either act when the callback is
548 after => 1, 616 after => 1,
549 cb => sub { $result_ready->send }, 617 cb => sub { $result_ready->send },
550 ); 618 );
551 619
552 # this "blocks" (while handling events) till the callback 620 # this "blocks" (while handling events) till the callback
553 # calls -<send 621 # calls ->send
554 $result_ready->recv; 622 $result_ready->recv;
555 623
556Example: wait for a timer, but take advantage of the fact that condition 624Example: wait for a timer, but take advantage of the fact that condition
557variables are also callable directly. 625variables are also callable directly.
558 626
622one. For example, a function that pings many hosts in parallel might want 690one. For example, a function that pings many hosts in parallel might want
623to use a condition variable for the whole process. 691to use a condition variable for the whole process.
624 692
625Every call to C<< ->begin >> will increment a counter, and every call to 693Every call to C<< ->begin >> will increment a counter, and every call to
626C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end 694C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
627>>, the (last) callback passed to C<begin> will be executed. That callback 695>>, the (last) callback passed to C<begin> will be executed, passing the
628is I<supposed> to call C<< ->send >>, but that is not required. If no 696condvar as first argument. That callback is I<supposed> to call C<< ->send
629callback was set, C<send> will be called without any arguments. 697>>, but that is not required. If no group callback was set, C<send> will
698be called without any arguments.
630 699
631You can think of C<< $cv->send >> giving you an OR condition (one call 700You can think of C<< $cv->send >> giving you an OR condition (one call
632sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND 701sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
633condition (all C<begin> calls must be C<end>'ed before the condvar sends). 702condition (all C<begin> calls must be C<end>'ed before the condvar sends).
634 703
661begung can potentially be zero: 730begung can potentially be zero:
662 731
663 my $cv = AnyEvent->condvar; 732 my $cv = AnyEvent->condvar;
664 733
665 my %result; 734 my %result;
666 $cv->begin (sub { $cv->send (\%result) }); 735 $cv->begin (sub { shift->send (\%result) });
667 736
668 for my $host (@list_of_hosts) { 737 for my $host (@list_of_hosts) {
669 $cv->begin; 738 $cv->begin;
670 ping_host_then_call_callback $host, sub { 739 ping_host_then_call_callback $host, sub {
671 $result{$host} = ...; 740 $result{$host} = ...;
746=item $cb = $cv->cb ($cb->($cv)) 815=item $cb = $cv->cb ($cb->($cv))
747 816
748This is a mutator function that returns the callback set and optionally 817This is a mutator function that returns the callback set and optionally
749replaces it before doing so. 818replaces it before doing so.
750 819
751The callback will be called when the condition becomes "true", i.e. when 820The callback will be called when the condition becomes (or already was)
752C<send> or C<croak> are called, with the only argument being the condition 821"true", i.e. when C<send> or C<croak> are called (or were called), with
753variable itself. Calling C<recv> inside the callback or at any later time 822the only argument being the condition variable itself. Calling C<recv>
754is guaranteed not to block. 823inside the callback or at any later time is guaranteed not to block.
755 824
756=back 825=back
757 826
758=head1 SUPPORTED EVENT LOOPS/BACKENDS 827=head1 SUPPORTED EVENT LOOPS/BACKENDS
759 828
762=over 4 831=over 4
763 832
764=item Backends that are autoprobed when no other event loop can be found. 833=item Backends that are autoprobed when no other event loop can be found.
765 834
766EV is the preferred backend when no other event loop seems to be in 835EV is the preferred backend when no other event loop seems to be in
767use. If EV is not installed, then AnyEvent will try Event, and, failing 836use. If EV is not installed, then AnyEvent will fall back to its own
768that, will fall back to its own pure-perl implementation, which is 837pure-perl implementation, which is available everywhere as it comes with
769available everywhere as it comes with AnyEvent itself. 838AnyEvent itself.
770 839
771 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 840 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
772 AnyEvent::Impl::Event based on Event, very stable, few glitches.
773 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 841 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
774 842
775=item Backends that are transparently being picked up when they are used. 843=item Backends that are transparently being picked up when they are used.
776 844
777These will be used when they are currently loaded when the first watcher 845These will be used when they are currently loaded when the first watcher
778is created, in which case it is assumed that the application is using 846is created, in which case it is assumed that the application is using
779them. This means that AnyEvent will automatically pick the right backend 847them. This means that AnyEvent will automatically pick the right backend
780when the main program loads an event module before anything starts to 848when the main program loads an event module before anything starts to
781create watchers. Nothing special needs to be done by the main program. 849create watchers. Nothing special needs to be done by the main program.
782 850
851 AnyEvent::Impl::Event based on Event, very stable, few glitches.
783 AnyEvent::Impl::Glib based on Glib, slow but very stable. 852 AnyEvent::Impl::Glib based on Glib, slow but very stable.
784 AnyEvent::Impl::Tk based on Tk, very broken. 853 AnyEvent::Impl::Tk based on Tk, very broken.
785 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 854 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
786 AnyEvent::Impl::POE based on POE, very slow, some limitations. 855 AnyEvent::Impl::POE based on POE, very slow, some limitations.
856 AnyEvent::Impl::Irssi used when running within irssi.
787 857
788=item Backends with special needs. 858=item Backends with special needs.
789 859
790Qt requires the Qt::Application to be instantiated first, but will 860Qt requires the Qt::Application to be instantiated first, but will
791otherwise be picked up automatically. As long as the main program 861otherwise be picked up automatically. As long as the main program
865event module detection too early, for example, L<AnyEvent::AIO> creates 935event module detection too early, for example, L<AnyEvent::AIO> creates
866and installs the global L<IO::AIO> watcher in a C<post_detect> block to 936and installs the global L<IO::AIO> watcher in a C<post_detect> block to
867avoid autodetecting the event module at load time. 937avoid autodetecting the event module at load time.
868 938
869If called in scalar or list context, then it creates and returns an object 939If called in scalar or list context, then it creates and returns an object
870that automatically removes the callback again when it is destroyed. See 940that automatically removes the callback again when it is destroyed (or
941C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
871L<Coro::BDB> for a case where this is useful. 942a case where this is useful.
943
944Example: Create a watcher for the IO::AIO module and store it in
945C<$WATCHER>. Only do so after the event loop is initialised, though.
946
947 our WATCHER;
948
949 my $guard = AnyEvent::post_detect {
950 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
951 };
952
953 # the ||= is important in case post_detect immediately runs the block,
954 # as to not clobber the newly-created watcher. assigning both watcher and
955 # post_detect guard to the same variable has the advantage of users being
956 # able to just C<undef $WATCHER> if the watcher causes them grief.
957
958 $WATCHER ||= $guard;
872 959
873=item @AnyEvent::post_detect 960=item @AnyEvent::post_detect
874 961
875If there are any code references in this array (you can C<push> to it 962If there are any code references in this array (you can C<push> to it
876before or after loading AnyEvent), then they will called directly after 963before or after loading AnyEvent), then they will called directly after
1043 1130
1044package AnyEvent; 1131package AnyEvent;
1045 1132
1046# basically a tuned-down version of common::sense 1133# basically a tuned-down version of common::sense
1047sub common_sense { 1134sub common_sense {
1048 # no warnings 1135 # from common:.sense 1.0
1049 ${^WARNING_BITS} ^= ${^WARNING_BITS}; 1136 ${^WARNING_BITS} = "\xfc\x3f\xf3\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x03";
1050 # use strict vars subs 1137 # use strict vars subs
1051 $^H |= 0x00000600; 1138 $^H |= 0x00000600;
1052} 1139}
1053 1140
1054BEGIN { AnyEvent::common_sense } 1141BEGIN { AnyEvent::common_sense }
1055 1142
1056use Carp (); 1143use Carp ();
1057 1144
1058our $VERSION = 4.83; 1145our $VERSION = '5.21';
1059our $MODEL; 1146our $MODEL;
1060 1147
1061our $AUTOLOAD; 1148our $AUTOLOAD;
1062our @ISA; 1149our @ISA;
1063 1150
1064our @REGISTRY; 1151our @REGISTRY;
1065
1066our $WIN32;
1067 1152
1068our $VERBOSE; 1153our $VERBOSE;
1069 1154
1070BEGIN { 1155BEGIN {
1071 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1156 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
1088 for reverse split /\s*,\s*/, 1173 for reverse split /\s*,\s*/,
1089 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1174 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1090} 1175}
1091 1176
1092my @models = ( 1177my @models = (
1093 [EV:: => AnyEvent::Impl::EV::], 1178 [EV:: => AnyEvent::Impl::EV:: , 1],
1094 [Event:: => AnyEvent::Impl::Event::],
1095 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 1179 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1096 # everything below here will not be autoprobed 1180 # everything below here will not (normally) be autoprobed
1097 # as the pureperl backend should work everywhere 1181 # as the pureperl backend should work everywhere
1098 # and is usually faster 1182 # and is usually faster
1183 [Event:: => AnyEvent::Impl::Event::, 1],
1099 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers 1184 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1100 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1185 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1186 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1101 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1187 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1102 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1188 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1103 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1189 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1104 [Wx:: => AnyEvent::Impl::POE::], 1190 [Wx:: => AnyEvent::Impl::POE::],
1105 [Prima:: => AnyEvent::Impl::POE::], 1191 [Prima:: => AnyEvent::Impl::POE::],
1106 # IO::Async is just too broken - we would need workarounds for its 1192 # IO::Async is just too broken - we would need workarounds for its
1107 # byzantine signal and broken child handling, among others. 1193 # byzantine signal and broken child handling, among others.
1108 # IO::Async is rather hard to detect, as it doesn't have any 1194 # IO::Async is rather hard to detect, as it doesn't have any
1109 # obvious default class. 1195 # obvious default class.
1110# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program 1196 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1111# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1197 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1112# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1198 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1199 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1113); 1200);
1114 1201
1115our %method = map +($_ => 1), 1202our %method = map +($_ => 1),
1116 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1203 qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1117 1204
1121 my ($cb) = @_; 1208 my ($cb) = @_;
1122 1209
1123 if ($MODEL) { 1210 if ($MODEL) {
1124 $cb->(); 1211 $cb->();
1125 1212
1126 1 1213 undef
1127 } else { 1214 } else {
1128 push @post_detect, $cb; 1215 push @post_detect, $cb;
1129 1216
1130 defined wantarray 1217 defined wantarray
1131 ? bless \$cb, "AnyEvent::Util::postdetect" 1218 ? bless \$cb, "AnyEvent::Util::postdetect"
1163 } 1250 }
1164 } 1251 }
1165 } 1252 }
1166 1253
1167 unless ($MODEL) { 1254 unless ($MODEL) {
1168 # try to load a model 1255 # try to autoload a model
1169
1170 for (@REGISTRY, @models) { 1256 for (@REGISTRY, @models) {
1171 my ($package, $model) = @$_; 1257 my ($package, $model, $autoload) = @$_;
1258 if (
1259 $autoload
1172 if (eval "require $package" 1260 and eval "require $package"
1173 and ${"$package\::VERSION"} > 0 1261 and ${"$package\::VERSION"} > 0
1174 and eval "require $model") { 1262 and eval "require $model"
1263 ) {
1175 $MODEL = $model; 1264 $MODEL = $model;
1176 warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2; 1265 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1177 last; 1266 last;
1178 } 1267 }
1179 } 1268 }
1180 1269
1181 $MODEL 1270 $MODEL
1222 # we assume CLOEXEC is already set by perl in all important cases 1311 # we assume CLOEXEC is already set by perl in all important cases
1223 1312
1224 ($fh2, $rw) 1313 ($fh2, $rw)
1225} 1314}
1226 1315
1316=head1 SIMPLIFIED AE API
1317
1318Starting with version 5.0, AnyEvent officially supports a second, much
1319simpler, API that is designed to reduce the calling, typing and memory
1320overhead.
1321
1322See the L<AE> manpage for details.
1323
1324=cut
1325
1326package AE;
1327
1328our $VERSION = $AnyEvent::VERSION;
1329
1330sub io($$$) {
1331 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1332}
1333
1334sub timer($$$) {
1335 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1336}
1337
1338sub signal($$) {
1339 AnyEvent->signal (signal => $_[0], cb => $_[1])
1340}
1341
1342sub child($$) {
1343 AnyEvent->child (pid => $_[0], cb => $_[1])
1344}
1345
1346sub idle($) {
1347 AnyEvent->idle (cb => $_[0])
1348}
1349
1350sub cv(;&) {
1351 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1352}
1353
1354sub now() {
1355 AnyEvent->now
1356}
1357
1358sub now_update() {
1359 AnyEvent->now_update
1360}
1361
1362sub time() {
1363 AnyEvent->time
1364}
1365
1227package AnyEvent::Base; 1366package AnyEvent::Base;
1228 1367
1229# default implementations for many methods 1368# default implementations for many methods
1230 1369
1231sub _time { 1370sub _time() {
1232 # probe for availability of Time::HiRes 1371 # probe for availability of Time::HiRes
1233 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1372 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1234 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1373 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1235 *_time = \&Time::HiRes::time; 1374 *_time = \&Time::HiRes::time;
1236 # if (eval "use POSIX (); (POSIX::times())... 1375 # if (eval "use POSIX (); (POSIX::times())...
1253} 1392}
1254 1393
1255# default implementation for ->signal 1394# default implementation for ->signal
1256 1395
1257our $HAVE_ASYNC_INTERRUPT; 1396our $HAVE_ASYNC_INTERRUPT;
1397
1398sub _have_async_interrupt() {
1399 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1400 && eval "use Async::Interrupt 1.02 (); 1")
1401 unless defined $HAVE_ASYNC_INTERRUPT;
1402
1403 $HAVE_ASYNC_INTERRUPT
1404}
1405
1258our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1406our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1259our (%SIG_ASY, %SIG_ASY_W); 1407our (%SIG_ASY, %SIG_ASY_W);
1260our ($SIG_COUNT, $SIG_TW); 1408our ($SIG_COUNT, $SIG_TW);
1261 1409
1262sub _signal_exec { 1410sub _signal_exec {
1263 $HAVE_ASYNC_INTERRUPT 1411 $HAVE_ASYNC_INTERRUPT
1264 ? $SIGPIPE_R->drain 1412 ? $SIGPIPE_R->drain
1265 : sysread $SIGPIPE_R, my $dummy, 9; 1413 : sysread $SIGPIPE_R, (my $dummy), 9;
1266 1414
1267 while (%SIG_EV) { 1415 while (%SIG_EV) {
1268 for (keys %SIG_EV) { 1416 for (keys %SIG_EV) {
1269 delete $SIG_EV{$_}; 1417 delete $SIG_EV{$_};
1270 $_->() for values %{ $SIG_CB{$_} || {} }; 1418 $_->() for values %{ $SIG_CB{$_} || {} };
1271 } 1419 }
1272 } 1420 }
1273} 1421}
1274 1422
1423# install a dummy wakeup watcher to reduce signal catching latency
1275sub _signal { 1424sub _sig_add() {
1276 my (undef, %arg) = @_; 1425 unless ($SIG_COUNT++) {
1426 # try to align timer on a full-second boundary, if possible
1427 my $NOW = AE::now;
1277 1428
1278 my $signal = uc $arg{signal} 1429 $SIG_TW = AE::timer
1279 or Carp::croak "required option 'signal' is missing"; 1430 $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1280 1431 $MAX_SIGNAL_LATENCY,
1281 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1432 sub { } # just for the PERL_ASYNC_CHECK
1282
1283 if ($HAVE_ASYNC_INTERRUPT) {
1284 # async::interrupt
1285
1286 $SIG_ASY{$signal} ||= do {
1287 my $asy = new Async::Interrupt
1288 cb => sub { undef $SIG_EV{$signal} },
1289 signal => $signal,
1290 pipe => [$SIGPIPE_R->filenos],
1291 ;
1292 $asy->pipe_autodrain (0);
1293
1294 $asy
1295 }; 1433 ;
1296
1297 } else {
1298 # pure perl
1299
1300 $SIG{$signal} ||= sub {
1301 local $!;
1302 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1303 undef $SIG_EV{$signal};
1304 };
1305
1306 # can't do signal processing without introducing races in pure perl,
1307 # so limit the signal latency.
1308 ++$SIG_COUNT;
1309 $SIG_TW ||= AnyEvent->timer (
1310 after => $MAX_SIGNAL_LATENCY,
1311 interval => $MAX_SIGNAL_LATENCY,
1312 cb => sub { }, # just for the PERL_ASYNC_CHECK
1313 );
1314 } 1434 }
1315
1316 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1317} 1435}
1318 1436
1319sub signal { 1437sub _sig_del {
1320 # probe for availability of Async::Interrupt
1321 if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
1322 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1323
1324 $HAVE_ASYNC_INTERRUPT = 1;
1325 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1326 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
1327
1328 } else {
1329 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1330
1331 require Fcntl;
1332
1333 if (AnyEvent::WIN32) {
1334 require AnyEvent::Util;
1335
1336 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1337 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1338 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1339 } else {
1340 pipe $SIGPIPE_R, $SIGPIPE_W;
1341 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1342 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1343
1344 # not strictly required, as $^F is normally 2, but let's make sure...
1345 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1346 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1347 }
1348
1349 $SIGPIPE_R
1350 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1351
1352 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1353 }
1354
1355 *signal = \&_signal;
1356 &signal
1357}
1358
1359sub AnyEvent::Base::signal::DESTROY {
1360 my ($signal, $cb) = @{$_[0]};
1361
1362 undef $SIG_TW 1438 undef $SIG_TW
1363 unless --$SIG_COUNT; 1439 unless --$SIG_COUNT;
1440}
1364 1441
1442our $_sig_name_init; $_sig_name_init = sub {
1443 eval q{ # poor man's autoloading
1444 undef $_sig_name_init;
1445
1446 if (_have_async_interrupt) {
1447 *sig2num = \&Async::Interrupt::sig2num;
1448 *sig2name = \&Async::Interrupt::sig2name;
1449 } else {
1450 require Config;
1451
1452 my %signame2num;
1453 @signame2num{ split ' ', $Config::Config{sig_name} }
1454 = split ' ', $Config::Config{sig_num};
1455
1456 my @signum2name;
1457 @signum2name[values %signame2num] = keys %signame2num;
1458
1459 *sig2num = sub($) {
1460 $_[0] > 0 ? shift : $signame2num{+shift}
1461 };
1462 *sig2name = sub ($) {
1463 $_[0] > 0 ? $signum2name[+shift] : shift
1464 };
1465 }
1466 };
1467 die if $@;
1468};
1469
1470sub sig2num ($) { &$_sig_name_init; &sig2num }
1471sub sig2name($) { &$_sig_name_init; &sig2name }
1472
1473sub signal {
1474 eval q{ # poor man's autoloading {}
1475 # probe for availability of Async::Interrupt
1476 if (_have_async_interrupt) {
1477 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1478
1479 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1480 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1481
1482 } else {
1483 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1484
1485 require Fcntl;
1486
1487 if (AnyEvent::WIN32) {
1488 require AnyEvent::Util;
1489
1490 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1491 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1492 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1493 } else {
1494 pipe $SIGPIPE_R, $SIGPIPE_W;
1495 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1496 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1497
1498 # not strictly required, as $^F is normally 2, but let's make sure...
1499 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1500 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1501 }
1502
1503 $SIGPIPE_R
1504 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1505
1506 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1507 }
1508
1509 *signal = sub {
1510 my (undef, %arg) = @_;
1511
1512 my $signal = uc $arg{signal}
1513 or Carp::croak "required option 'signal' is missing";
1514
1515 if ($HAVE_ASYNC_INTERRUPT) {
1516 # async::interrupt
1517
1518 $signal = sig2num $signal;
1519 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1520
1521 $SIG_ASY{$signal} ||= new Async::Interrupt
1522 cb => sub { undef $SIG_EV{$signal} },
1523 signal => $signal,
1524 pipe => [$SIGPIPE_R->filenos],
1525 pipe_autodrain => 0,
1526 ;
1527
1528 } else {
1529 # pure perl
1530
1531 # AE::Util has been loaded in signal
1532 $signal = sig2name $signal;
1533 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1534
1535 $SIG{$signal} ||= sub {
1536 local $!;
1537 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1538 undef $SIG_EV{$signal};
1539 };
1540
1541 # can't do signal processing without introducing races in pure perl,
1542 # so limit the signal latency.
1543 _sig_add;
1544 }
1545
1546 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1547 };
1548
1549 *AnyEvent::Base::signal::DESTROY = sub {
1550 my ($signal, $cb) = @{$_[0]};
1551
1552 _sig_del;
1553
1365 delete $SIG_CB{$signal}{$cb}; 1554 delete $SIG_CB{$signal}{$cb};
1366 1555
1556 $HAVE_ASYNC_INTERRUPT
1557 ? delete $SIG_ASY{$signal}
1367 # delete doesn't work with older perls - they then 1558 : # delete doesn't work with older perls - they then
1368 # print weird messages, or just unconditionally exit 1559 # print weird messages, or just unconditionally exit
1369 # instead of getting the default action. 1560 # instead of getting the default action.
1370 undef $SIG{$signal} 1561 undef $SIG{$signal}
1371 unless keys %{ $SIG_CB{$signal} }; 1562 unless keys %{ $SIG_CB{$signal} };
1563 };
1564 };
1565 die if $@;
1566 &signal
1372} 1567}
1373 1568
1374# default implementation for ->child 1569# default implementation for ->child
1375 1570
1376our %PID_CB; 1571our %PID_CB;
1377our $CHLD_W; 1572our $CHLD_W;
1378our $CHLD_DELAY_W; 1573our $CHLD_DELAY_W;
1379our $WNOHANG; 1574our $WNOHANG;
1380 1575
1576sub _emit_childstatus($$) {
1577 my (undef, $rpid, $rstatus) = @_;
1578
1579 $_->($rpid, $rstatus)
1580 for values %{ $PID_CB{$rpid} || {} },
1581 values %{ $PID_CB{0} || {} };
1582}
1583
1381sub _sigchld { 1584sub _sigchld {
1585 my $pid;
1586
1587 AnyEvent->_emit_childstatus ($pid, $?)
1382 while (0 < (my $pid = waitpid -1, $WNOHANG)) { 1588 while ($pid = waitpid -1, $WNOHANG) > 0;
1383 $_->($pid, $?)
1384 for values %{ $PID_CB{$pid} || {} },
1385 values %{ $PID_CB{0} || {} };
1386 }
1387} 1589}
1388 1590
1389sub child { 1591sub child {
1390 my (undef, %arg) = @_; 1592 my (undef, %arg) = @_;
1391 1593
1398 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ 1600 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1399 ? 1 1601 ? 1
1400 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1602 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1401 1603
1402 unless ($CHLD_W) { 1604 unless ($CHLD_W) {
1403 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1605 $CHLD_W = AE::signal CHLD => \&_sigchld;
1404 # child could be a zombie already, so make at least one round 1606 # child could be a zombie already, so make at least one round
1405 &_sigchld; 1607 &_sigchld;
1406 } 1608 }
1407 1609
1408 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1610 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1434 # never use more then 50% of the time for the idle watcher, 1636 # never use more then 50% of the time for the idle watcher,
1435 # within some limits 1637 # within some limits
1436 $w = 0.0001 if $w < 0.0001; 1638 $w = 0.0001 if $w < 0.0001;
1437 $w = 5 if $w > 5; 1639 $w = 5 if $w > 5;
1438 1640
1439 $w = AnyEvent->timer (after => $w, cb => $rcb); 1641 $w = AE::timer $w, 0, $rcb;
1440 } else { 1642 } else {
1441 # clean up... 1643 # clean up...
1442 undef $w; 1644 undef $w;
1443 undef $rcb; 1645 undef $rcb;
1444 } 1646 }
1445 }; 1647 };
1446 1648
1447 $w = AnyEvent->timer (after => 0.05, cb => $rcb); 1649 $w = AE::timer 0.05, 0, $rcb;
1448 1650
1449 bless \\$cb, "AnyEvent::Base::idle" 1651 bless \\$cb, "AnyEvent::Base::idle"
1450} 1652}
1451 1653
1452sub AnyEvent::Base::idle::DESTROY { 1654sub AnyEvent::Base::idle::DESTROY {
1506 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1708 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1507 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1709 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1508} 1710}
1509 1711
1510sub cb { 1712sub cb {
1511 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1713 my $cv = shift;
1714
1715 @_
1716 and $cv->{_ae_cb} = shift
1717 and $cv->{_ae_sent}
1718 and (delete $cv->{_ae_cb})->($cv);
1719
1512 $_[0]{_ae_cb} 1720 $cv->{_ae_cb}
1513} 1721}
1514 1722
1515sub begin { 1723sub begin {
1516 ++$_[0]{_ae_counter}; 1724 ++$_[0]{_ae_counter};
1517 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1725 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1726 warn "read: $input\n"; # output what has been read 1934 warn "read: $input\n"; # output what has been read
1727 $cv->send if $input =~ /^q/i; # quit program if /^q/i 1935 $cv->send if $input =~ /^q/i; # quit program if /^q/i
1728 }, 1936 },
1729 ); 1937 );
1730 1938
1731 my $time_watcher; # can only be used once
1732
1733 sub new_timer {
1734 $timer = AnyEvent->timer (after => 1, cb => sub { 1939 my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1735 warn "timeout\n"; # print 'timeout' about every second 1940 warn "timeout\n"; # print 'timeout' at most every second
1736 &new_timer; # and restart the time
1737 }); 1941 });
1738 }
1739
1740 new_timer; # create first timer
1741 1942
1742 $cv->recv; # wait until user enters /^q/i 1943 $cv->recv; # wait until user enters /^q/i
1743 1944
1744=head1 REAL-WORLD EXAMPLE 1945=head1 REAL-WORLD EXAMPLE
1745 1946
1876through AnyEvent. The benchmark creates a lot of timers (with a zero 2077through AnyEvent. The benchmark creates a lot of timers (with a zero
1877timeout) and I/O watchers (watching STDOUT, a pty, to become writable, 2078timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1878which it is), lets them fire exactly once and destroys them again. 2079which it is), lets them fire exactly once and destroys them again.
1879 2080
1880Source code for this benchmark is found as F<eg/bench> in the AnyEvent 2081Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1881distribution. 2082distribution. It uses the L<AE> interface, which makes a real difference
2083for the EV and Perl backends only.
1882 2084
1883=head3 Explanation of the columns 2085=head3 Explanation of the columns
1884 2086
1885I<watcher> is the number of event watchers created/destroyed. Since 2087I<watcher> is the number of event watchers created/destroyed. Since
1886different event models feature vastly different performances, each event 2088different event models feature vastly different performances, each event
1907watcher. 2109watcher.
1908 2110
1909=head3 Results 2111=head3 Results
1910 2112
1911 name watchers bytes create invoke destroy comment 2113 name watchers bytes create invoke destroy comment
1912 EV/EV 400000 224 0.47 0.35 0.27 EV native interface 2114 EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1913 EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers 2115 EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1914 CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal 2116 Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1915 Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation 2117 Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1916 Event/Event 16000 517 32.20 31.80 0.81 Event native interface 2118 Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1917 Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers 2119 Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
1918 IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll 2120 IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
1919 IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll 2121 IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1920 Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour 2122 Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1921 Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers 2123 Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1922 POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event 2124 POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1923 POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select 2125 POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1924 2126
1925=head3 Discussion 2127=head3 Discussion
1926 2128
1927The benchmark does I<not> measure scalability of the event loop very 2129The benchmark does I<not> measure scalability of the event loop very
1928well. For example, a select-based event loop (such as the pure perl one) 2130well. For example, a select-based event loop (such as the pure perl one)
1940benchmark machine, handling an event takes roughly 1600 CPU cycles with 2142benchmark machine, handling an event takes roughly 1600 CPU cycles with
1941EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU 2143EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1942cycles with POE. 2144cycles with POE.
1943 2145
1944C<EV> is the sole leader regarding speed and memory use, which are both 2146C<EV> is the sole leader regarding speed and memory use, which are both
1945maximal/minimal, respectively. Even when going through AnyEvent, it uses 2147maximal/minimal, respectively. When using the L<AE> API there is zero
2148overhead (when going through the AnyEvent API create is about 5-6 times
2149slower, with other times being equal, so still uses far less memory than
1946far less memory than any other event loop and is still faster than Event 2150any other event loop and is still faster than Event natively).
1947natively.
1948 2151
1949The pure perl implementation is hit in a few sweet spots (both the 2152The pure perl implementation is hit in a few sweet spots (both the
1950constant timeout and the use of a single fd hit optimisations in the perl 2153constant timeout and the use of a single fd hit optimisations in the perl
1951interpreter and the backend itself). Nevertheless this shows that it 2154interpreter and the backend itself). Nevertheless this shows that it
1952adds very little overhead in itself. Like any select-based backend its 2155adds very little overhead in itself. Like any select-based backend its
2026In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100 2229In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
2027(1%) are active. This mirrors the activity of large servers with many 2230(1%) are active. This mirrors the activity of large servers with many
2028connections, most of which are idle at any one point in time. 2231connections, most of which are idle at any one point in time.
2029 2232
2030Source code for this benchmark is found as F<eg/bench2> in the AnyEvent 2233Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
2031distribution. 2234distribution. It uses the L<AE> interface, which makes a real difference
2235for the EV and Perl backends only.
2032 2236
2033=head3 Explanation of the columns 2237=head3 Explanation of the columns
2034 2238
2035I<sockets> is the number of sockets, and twice the number of "servers" (as 2239I<sockets> is the number of sockets, and twice the number of "servers" (as
2036each server has a read and write socket end). 2240each server has a read and write socket end).
2044a new one that moves the timeout into the future. 2248a new one that moves the timeout into the future.
2045 2249
2046=head3 Results 2250=head3 Results
2047 2251
2048 name sockets create request 2252 name sockets create request
2049 EV 20000 69.01 11.16 2253 EV 20000 62.66 7.99
2050 Perl 20000 73.32 35.87 2254 Perl 20000 68.32 32.64
2051 IOAsync 20000 157.00 98.14 epoll 2255 IOAsync 20000 174.06 101.15 epoll
2052 IOAsync 20000 159.31 616.06 poll 2256 IOAsync 20000 174.67 610.84 poll
2053 Event 20000 212.62 257.32 2257 Event 20000 202.69 242.91
2054 Glib 20000 651.16 1896.30 2258 Glib 20000 557.01 1689.52
2055 POE 20000 349.67 12317.24 uses POE::Loop::Event 2259 POE 20000 341.54 12086.32 uses POE::Loop::Event
2056 2260
2057=head3 Discussion 2261=head3 Discussion
2058 2262
2059This benchmark I<does> measure scalability and overall performance of the 2263This benchmark I<does> measure scalability and overall performance of the
2060particular event loop. 2264particular event loop.
2186As you can see, the AnyEvent + EV combination even beats the 2390As you can see, the AnyEvent + EV combination even beats the
2187hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl 2391hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2188backend easily beats IO::Lambda and POE. 2392backend easily beats IO::Lambda and POE.
2189 2393
2190And even the 100% non-blocking version written using the high-level (and 2394And even the 100% non-blocking version written using the high-level (and
2191slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a 2395slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2192large margin, even though it does all of DNS, tcp-connect and socket I/O 2396higher level ("unoptimised") abstractions by a large margin, even though
2193in a non-blocking way. 2397it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2194 2398
2195The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and 2399The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2196F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are 2400F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2197part of the IO::lambda distribution and were used without any changes. 2401part of the IO::Lambda distribution and were used without any changes.
2198 2402
2199 2403
2200=head1 SIGNALS 2404=head1 SIGNALS
2201 2405
2202AnyEvent currently installs handlers for these signals: 2406AnyEvent currently installs handlers for these signals:
2245 2449
2246That does not mean that AnyEvent won't take advantage of some additional 2450That does not mean that AnyEvent won't take advantage of some additional
2247modules if they are installed. 2451modules if they are installed.
2248 2452
2249This section epxlains which additional modules will be used, and how they 2453This section epxlains which additional modules will be used, and how they
2250affect AnyEvent's operetion. 2454affect AnyEvent's operation.
2251 2455
2252=over 4 2456=over 4
2253 2457
2254=item L<Async::Interrupt> 2458=item L<Async::Interrupt>
2255 2459
2256This slightly arcane module is used to implement fast signal handling: To 2460This slightly arcane module is used to implement fast signal handling: To
2257my knowledge, there is no way to do completely race-free and quick 2461my knowledge, there is no way to do completely race-free and quick
2258signal handling in pure perl. To ensure that signals still get 2462signal handling in pure perl. To ensure that signals still get
2259delivered, AnyEvent will start an interval timer to wake up perl (and 2463delivered, AnyEvent will start an interval timer to wake up perl (and
2260catch the signals) with soemd elay (default is 10 seconds, look for 2464catch the signals) with some delay (default is 10 seconds, look for
2261C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2465C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2262 2466
2263If this module is available, then it will be used to implement signal 2467If this module is available, then it will be used to implement signal
2264catching, which means that signals will not be delayed, and the event loop 2468catching, which means that signals will not be delayed, and the event loop
2265will not be interrupted regularly, which is more efficient (And good for 2469will not be interrupted regularly, which is more efficient (And good for
2266battery life on laptops). 2470battery life on laptops).
2267 2471
2268This affects not just the pure-perl event loop, but also other event loops 2472This affects not just the pure-perl event loop, but also other event loops
2269that have no signal handling on their own (e.g. Glib, Tk, Qt). 2473that have no signal handling on their own (e.g. Glib, Tk, Qt).
2474
2475Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
2476and either employ their own workarounds (POE) or use AnyEvent's workaround
2477(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
2478does nothing for those backends.
2270 2479
2271=item L<EV> 2480=item L<EV>
2272 2481
2273This module isn't really "optional", as it is simply one of the backend 2482This module isn't really "optional", as it is simply one of the backend
2274event loops that AnyEvent can use. However, it is simply the best event 2483event loops that AnyEvent can use. However, it is simply the best event
2286lot less memory), but otherwise doesn't affect guard operation much. It is 2495lot less memory), but otherwise doesn't affect guard operation much. It is
2287purely used for performance. 2496purely used for performance.
2288 2497
2289=item L<JSON> and L<JSON::XS> 2498=item L<JSON> and L<JSON::XS>
2290 2499
2291This module is required when you want to read or write JSON data via 2500One of these modules is required when you want to read or write JSON data
2292L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2501via L<AnyEvent::Handle>. It is also written in pure-perl, but can take
2293advantage of the ulta-high-speed L<JSON::XS> module when it is installed. 2502advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2294 2503
2295In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is 2504In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2296installed. 2505installed.
2297 2506
2298=item L<Net::SSLeay> 2507=item L<Net::SSLeay>
2365L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2574L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2366 2575
2367Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 2576Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2368L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 2577L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2369L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 2578L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2370L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>. 2579L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2371 2580
2372Non-blocking file handles, sockets, TCP clients and 2581Non-blocking file handles, sockets, TCP clients and
2373servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2582servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2374 2583
2375Asynchronous DNS: L<AnyEvent::DNS>. 2584Asynchronous DNS: L<AnyEvent::DNS>.

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