1 | NAME |
1 | NAME |
2 | AnyEvent - provide framework for multiple event loops |
2 | AnyEvent - provide framework for multiple event loops |
3 | |
3 | |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported |
5 | loops |
5 | event loops. |
6 | |
6 | |
7 | SYNOPSIS |
7 | SYNOPSIS |
8 | use AnyEvent; |
8 | use AnyEvent; |
9 | |
9 | |
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10 | # file descriptor readable |
10 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
11 | |
12 | |
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13 | # one-shot or repeating timers |
12 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
14 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
13 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
15 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
14 | |
16 | |
15 | print AnyEvent->now; # prints current event loop time |
17 | print AnyEvent->now; # prints current event loop time |
16 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
18 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
17 | |
19 | |
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20 | # POSIX signal |
18 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
21 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
19 | |
22 | |
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23 | # child process exit |
20 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
24 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
21 | my ($pid, $status) = @_; |
25 | my ($pid, $status) = @_; |
22 | ... |
26 | ... |
23 | }); |
27 | }); |
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28 | |
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29 | # called when event loop idle (if applicable) |
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30 | my $w = AnyEvent->idle (cb => sub { ... }); |
24 | |
31 | |
25 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
32 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
26 | $w->send; # wake up current and all future recv's |
33 | $w->send; # wake up current and all future recv's |
27 | $w->recv; # enters "main loop" till $condvar gets ->send |
34 | $w->recv; # enters "main loop" till $condvar gets ->send |
28 | # use a condvar in callback mode: |
35 | # use a condvar in callback mode: |
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314 | In either case, if you care (and in most cases, you don't), then you |
321 | In either case, if you care (and in most cases, you don't), then you |
315 | can get whatever behaviour you want with any event loop, by taking |
322 | can get whatever behaviour you want with any event loop, by taking |
316 | the difference between "AnyEvent->time" and "AnyEvent->now" into |
323 | the difference between "AnyEvent->time" and "AnyEvent->now" into |
317 | account. |
324 | account. |
318 | |
325 | |
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326 | AnyEvent->now_update |
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327 | Some event loops (such as EV or AnyEvent::Impl::Perl) cache the |
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328 | current time for each loop iteration (see the discussion of |
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329 | AnyEvent->now, above). |
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330 | |
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331 | When a callback runs for a long time (or when the process sleeps), |
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332 | then this "current" time will differ substantially from the real |
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333 | time, which might affect timers and time-outs. |
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334 | |
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335 | When this is the case, you can call this method, which will update |
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336 | the event loop's idea of "current time". |
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337 | |
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338 | Note that updating the time *might* cause some events to be handled. |
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339 | |
319 | SIGNAL WATCHERS |
340 | SIGNAL WATCHERS |
320 | You can watch for signals using a signal watcher, "signal" is the signal |
341 | You can watch for signals using a signal watcher, "signal" is the signal |
321 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
342 | *name* in uppercase and without any "SIG" prefix, "cb" is the Perl |
322 | callback to be invoked whenever a signal occurs. |
343 | callback to be invoked whenever a signal occurs. |
323 | |
344 | |
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359 | |
380 | |
360 | There is a slight catch to child watchers, however: you usually start |
381 | There is a slight catch to child watchers, however: you usually start |
361 | them *after* the child process was created, and this means the process |
382 | them *after* the child process was created, and this means the process |
362 | could have exited already (and no SIGCHLD will be sent anymore). |
383 | could have exited already (and no SIGCHLD will be sent anymore). |
363 | |
384 | |
364 | Not all event models handle this correctly (POE doesn't), but even for |
385 | Not all event models handle this correctly (neither POE nor IO::Async |
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386 | do, see their AnyEvent::Impl manpages for details), but even for event |
365 | event models that *do* handle this correctly, they usually need to be |
387 | models that *do* handle this correctly, they usually need to be loaded |
366 | loaded before the process exits (i.e. before you fork in the first |
388 | before the process exits (i.e. before you fork in the first place). |
367 | place). |
389 | AnyEvent's pure perl event loop handles all cases correctly regardless |
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390 | of when you start the watcher. |
368 | |
391 | |
369 | This means you cannot create a child watcher as the very first thing in |
392 | This means you cannot create a child watcher as the very first thing in |
370 | an AnyEvent program, you *have* to create at least one watcher before |
393 | an AnyEvent program, you *have* to create at least one watcher before |
371 | you "fork" the child (alternatively, you can call "AnyEvent::detect"). |
394 | you "fork" the child (alternatively, you can call "AnyEvent::detect"). |
372 | |
395 | |
373 | Example: fork a process and wait for it |
396 | Example: fork a process and wait for it |
374 | |
397 | |
375 | my $done = AnyEvent->condvar; |
398 | my $done = AnyEvent->condvar; |
376 | |
399 | |
377 | my $pid = fork or exit 5; |
400 | my $pid = fork or exit 5; |
378 | |
401 | |
379 | my $w = AnyEvent->child ( |
402 | my $w = AnyEvent->child ( |
380 | pid => $pid, |
403 | pid => $pid, |
381 | cb => sub { |
404 | cb => sub { |
382 | my ($pid, $status) = @_; |
405 | my ($pid, $status) = @_; |
383 | warn "pid $pid exited with status $status"; |
406 | warn "pid $pid exited with status $status"; |
384 | $done->send; |
407 | $done->send; |
385 | }, |
408 | }, |
386 | ); |
409 | ); |
387 | |
410 | |
388 | # do something else, then wait for process exit |
411 | # do something else, then wait for process exit |
389 | $done->recv; |
412 | $done->recv; |
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413 | |
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414 | IDLE WATCHERS |
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415 | Sometimes there is a need to do something, but it is not so important to |
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416 | do it instantly, but only when there is nothing better to do. This |
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417 | "nothing better to do" is usually defined to be "no other events need |
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418 | attention by the event loop". |
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419 | |
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420 | Idle watchers ideally get invoked when the event loop has nothing better |
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421 | to do, just before it would block the process to wait for new events. |
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422 | Instead of blocking, the idle watcher is invoked. |
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423 | |
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424 | Most event loops unfortunately do not really support idle watchers (only |
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425 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
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426 | will simply call the callback "from time to time". |
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427 | |
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428 | Example: read lines from STDIN, but only process them when the program |
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429 | is otherwise idle: |
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430 | |
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431 | my @lines; # read data |
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432 | my $idle_w; |
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433 | my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
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434 | push @lines, scalar <STDIN>; |
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435 | |
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436 | # start an idle watcher, if not already done |
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437 | $idle_w ||= AnyEvent->idle (cb => sub { |
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438 | # handle only one line, when there are lines left |
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439 | if (my $line = shift @lines) { |
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440 | print "handled when idle: $line"; |
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441 | } else { |
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442 | # otherwise disable the idle watcher again |
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443 | undef $idle_w; |
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444 | } |
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445 | }); |
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446 | }); |
390 | |
447 | |
391 | CONDITION VARIABLES |
448 | CONDITION VARIABLES |
392 | If you are familiar with some event loops you will know that all of them |
449 | If you are familiar with some event loops you will know that all of them |
393 | require you to run some blocking "loop", "run" or similar function that |
450 | require you to run some blocking "loop", "run" or similar function that |
394 | will actively watch for new events and call your callbacks. |
451 | will actively watch for new events and call your callbacks. |
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642 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
699 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
643 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
700 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
644 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
701 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
645 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
702 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
646 | |
703 | |
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704 | # warning, support for IO::Async is only partial, as it is too broken |
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705 | # and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async. |
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706 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs). |
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707 | |
647 | There is no support for WxWidgets, as WxWidgets has no support for |
708 | There is no support for WxWidgets, as WxWidgets has no support for |
648 | watching file handles. However, you can use WxWidgets through the |
709 | watching file handles. However, you can use WxWidgets through the |
649 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
710 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
650 | second, which was considered to be too horrible to even consider for |
711 | second, which was considered to be too horrible to even consider for |
651 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by |
712 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by |
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828 | "condvar->recv"), the Event and EV modules call "$Event/EV::DIED->()", |
889 | "condvar->recv"), the Event and EV modules call "$Event/EV::DIED->()", |
829 | Glib uses "install_exception_handler" and so on. |
890 | Glib uses "install_exception_handler" and so on. |
830 | |
891 | |
831 | ENVIRONMENT VARIABLES |
892 | ENVIRONMENT VARIABLES |
832 | The following environment variables are used by this module or its |
893 | The following environment variables are used by this module or its |
833 | submodules: |
894 | submodules. |
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895 | |
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896 | Note that AnyEvent will remove *all* environment variables starting with |
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897 | "PERL_ANYEVENT_" from %ENV when it is loaded while taint mode is |
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898 | enabled. |
834 | |
899 | |
835 | "PERL_ANYEVENT_VERBOSE" |
900 | "PERL_ANYEVENT_VERBOSE" |
836 | By default, AnyEvent will be completely silent except in fatal |
901 | By default, AnyEvent will be completely silent except in fatal |
837 | conditions. You can set this environment variable to make AnyEvent |
902 | conditions. You can set this environment variable to make AnyEvent |
838 | more talkative. |
903 | more talkative. |
… | |
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847 | "PERL_ANYEVENT_STRICT" |
912 | "PERL_ANYEVENT_STRICT" |
848 | AnyEvent does not do much argument checking by default, as thorough |
913 | AnyEvent does not do much argument checking by default, as thorough |
849 | argument checking is very costly. Setting this variable to a true |
914 | argument checking is very costly. Setting this variable to a true |
850 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
915 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
851 | thoroughly check the arguments passed to most method calls. If it |
916 | thoroughly check the arguments passed to most method calls. If it |
852 | finds any problems it will croak. |
917 | finds any problems, it will croak. |
853 | |
918 | |
854 | In other words, enables "strict" mode. |
919 | In other words, enables "strict" mode. |
855 | |
920 | |
856 | Unlike "use strict", it is definitely recommended ot keep it off in |
921 | Unlike "use strict", it is definitely recommended to keep it off in |
857 | production. Keeping "PERL_ANYEVENT_STRICT=1" in your environment |
922 | production. Keeping "PERL_ANYEVENT_STRICT=1" in your environment |
858 | while developing programs can be very useful, however. |
923 | while developing programs can be very useful, however. |
859 | |
924 | |
860 | "PERL_ANYEVENT_MODEL" |
925 | "PERL_ANYEVENT_MODEL" |
861 | This can be used to specify the event model to be used by AnyEvent, |
926 | This can be used to specify the event model to be used by AnyEvent, |
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1149 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1214 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1150 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1215 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1151 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1216 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1152 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1217 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1153 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1218 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
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1219 | IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll |
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1220 | IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll |
1154 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1221 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1155 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1222 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1156 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1223 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1157 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1224 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1158 | |
1225 | |
… | |
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1187 | few of them active), of course, but this was not subject of this |
1254 | few of them active), of course, but this was not subject of this |
1188 | benchmark. |
1255 | benchmark. |
1189 | |
1256 | |
1190 | The "Event" module has a relatively high setup and callback invocation |
1257 | The "Event" module has a relatively high setup and callback invocation |
1191 | cost, but overall scores in on the third place. |
1258 | cost, but overall scores in on the third place. |
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1259 | |
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1260 | "IO::Async" performs admirably well, about on par with "Event", even |
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1261 | when using its pure perl backend. |
1192 | |
1262 | |
1193 | "Glib"'s memory usage is quite a bit higher, but it features a faster |
1263 | "Glib"'s memory usage is quite a bit higher, but it features a faster |
1194 | callback invocation and overall ends up in the same class as "Event". |
1264 | callback invocation and overall ends up in the same class as "Event". |
1195 | However, Glib scales extremely badly, doubling the number of watchers |
1265 | However, Glib scales extremely badly, doubling the number of watchers |
1196 | increases the processing time by more than a factor of four, making it |
1266 | increases the processing time by more than a factor of four, making it |
… | |
… | |
1267 | single "request", that is, reading the token from the pipe and |
1337 | single "request", that is, reading the token from the pipe and |
1268 | forwarding it to another server. This includes deleting the old timeout |
1338 | forwarding it to another server. This includes deleting the old timeout |
1269 | and creating a new one that moves the timeout into the future. |
1339 | and creating a new one that moves the timeout into the future. |
1270 | |
1340 | |
1271 | Results |
1341 | Results |
1272 | name sockets create request |
1342 | name sockets create request |
1273 | EV 20000 69.01 11.16 |
1343 | EV 20000 69.01 11.16 |
1274 | Perl 20000 73.32 35.87 |
1344 | Perl 20000 73.32 35.87 |
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1345 | IOAsync 20000 157.00 98.14 epoll |
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1346 | IOAsync 20000 159.31 616.06 poll |
1275 | Event 20000 212.62 257.32 |
1347 | Event 20000 212.62 257.32 |
1276 | Glib 20000 651.16 1896.30 |
1348 | Glib 20000 651.16 1896.30 |
1277 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1349 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1278 | |
1350 | |
1279 | Discussion |
1351 | Discussion |
1280 | This benchmark *does* measure scalability and overall performance of the |
1352 | This benchmark *does* measure scalability and overall performance of the |
1281 | particular event loop. |
1353 | particular event loop. |
1282 | |
1354 | |
1283 | EV is again fastest. Since it is using epoll on my system, the setup |
1355 | EV is again fastest. Since it is using epoll on my system, the setup |
1284 | time is relatively high, though. |
1356 | time is relatively high, though. |
1285 | |
1357 | |
1286 | Perl surprisingly comes second. It is much faster than the C-based event |
1358 | Perl surprisingly comes second. It is much faster than the C-based event |
1287 | loops Event and Glib. |
1359 | loops Event and Glib. |
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1360 | |
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1361 | IO::Async performs very well when using its epoll backend, and still |
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1362 | quite good compared to Glib when using its pure perl backend. |
1288 | |
1363 | |
1289 | Event suffers from high setup time as well (look at its code and you |
1364 | Event suffers from high setup time as well (look at its code and you |
1290 | will understand why). Callback invocation also has a high overhead |
1365 | will understand why). Callback invocation also has a high overhead |
1291 | compared to the "$_->() for .."-style loop that the Perl event loop |
1366 | compared to the "$_->() for .."-style loop that the Perl event loop |
1292 | uses. Event uses select or poll in basically all documented |
1367 | uses. Event uses select or poll in basically all documented |
… | |
… | |
1343 | |
1418 | |
1344 | Summary |
1419 | Summary |
1345 | * C-based event loops perform very well with small number of watchers, |
1420 | * C-based event loops perform very well with small number of watchers, |
1346 | as the management overhead dominates. |
1421 | as the management overhead dominates. |
1347 | |
1422 | |
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1423 | THE IO::Lambda BENCHMARK |
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1424 | Recently I was told about the benchmark in the IO::Lambda manpage, which |
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1425 | could be misinterpreted to make AnyEvent look bad. In fact, the |
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1426 | benchmark simply compares IO::Lambda with POE, and IO::Lambda looks |
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1427 | better (which shouldn't come as a surprise to anybody). As such, the |
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1428 | benchmark is fine, and mostly shows that the AnyEvent backend from |
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1429 | IO::Lambda isn't very optimal. But how would AnyEvent compare when used |
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1430 | without the extra baggage? To explore this, I wrote the equivalent |
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1431 | benchmark for AnyEvent. |
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1432 | |
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1433 | The benchmark itself creates an echo-server, and then, for 500 times, |
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1434 | connects to the echo server, sends a line, waits for the reply, and then |
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1435 | creates the next connection. This is a rather bad benchmark, as it |
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1436 | doesn't test the efficiency of the framework or much non-blocking I/O, |
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1437 | but it is a benchmark nevertheless. |
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1438 | |
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1439 | name runtime |
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1440 | Lambda/select 0.330 sec |
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1441 | + optimized 0.122 sec |
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1442 | Lambda/AnyEvent 0.327 sec |
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1443 | + optimized 0.138 sec |
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1444 | Raw sockets/select 0.077 sec |
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1445 | POE/select, components 0.662 sec |
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1446 | POE/select, raw sockets 0.226 sec |
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1447 | POE/select, optimized 0.404 sec |
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1448 | |
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1449 | AnyEvent/select/nb 0.085 sec |
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1450 | AnyEvent/EV/nb 0.068 sec |
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1451 | +state machine 0.134 sec |
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1452 | |
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1453 | The benchmark is also a bit unfair (my fault): the IO::Lambda/POE |
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1454 | benchmarks actually make blocking connects and use 100% blocking I/O, |
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1455 | defeating the purpose of an event-based solution. All of the newly |
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1456 | written AnyEvent benchmarks use 100% non-blocking connects (using |
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1457 | AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS |
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1458 | resolver), so AnyEvent is at a disadvantage here, as non-blocking |
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1459 | connects generally require a lot more bookkeeping and event handling |
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1460 | than blocking connects (which involve a single syscall only). |
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1461 | |
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1462 | The last AnyEvent benchmark additionally uses AnyEvent::Handle, which |
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1463 | offers similar expressive power as POE and IO::Lambda, using |
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1464 | conventional Perl syntax. This means that both the echo server and the |
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1465 | client are 100% non-blocking, further placing it at a disadvantage. |
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1466 | |
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1467 | As you can see, the AnyEvent + EV combination even beats the |
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1468 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
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1469 | backend easily beats IO::Lambda and POE. |
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1470 | |
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1471 | And even the 100% non-blocking version written using the high-level (and |
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1472 | slow :) AnyEvent::Handle abstraction beats both POE and IO::Lambda by a |
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1473 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
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1474 | in a non-blocking way. |
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1475 | |
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1476 | The two AnyEvent benchmarks programs can be found as eg/ae0.pl and |
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1477 | eg/ae2.pl in the AnyEvent distribution, the remaining benchmarks are |
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1478 | part of the IO::lambda distribution and were used without any changes. |
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1479 | |
1348 | SIGNALS |
1480 | SIGNALS |
1349 | AnyEvent currently installs handlers for these signals: |
1481 | AnyEvent currently installs handlers for these signals: |
1350 | |
1482 | |
1351 | SIGCHLD |
1483 | SIGCHLD |
1352 | A handler for "SIGCHLD" is installed by AnyEvent's child watcher |
1484 | A handler for "SIGCHLD" is installed by AnyEvent's child watcher |
1353 | emulation for event loops that do not support them natively. Also, |
1485 | emulation for event loops that do not support them natively. Also, |
1354 | some event loops install a similar handler. |
1486 | some event loops install a similar handler. |
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1487 | |
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1488 | If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent |
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1489 | will reset it to default, to avoid losing child exit statuses. |
1355 | |
1490 | |
1356 | SIGPIPE |
1491 | SIGPIPE |
1357 | A no-op handler is installed for "SIGPIPE" when $SIG{PIPE} is |
1492 | A no-op handler is installed for "SIGPIPE" when $SIG{PIPE} is |
1358 | "undef" when AnyEvent gets loaded. |
1493 | "undef" when AnyEvent gets loaded. |
1359 | |
1494 | |
… | |
… | |
1387 | |
1522 | |
1388 | You can make AnyEvent completely ignore this variable by deleting it |
1523 | You can make AnyEvent completely ignore this variable by deleting it |
1389 | before the first watcher gets created, e.g. with a "BEGIN" block: |
1524 | before the first watcher gets created, e.g. with a "BEGIN" block: |
1390 | |
1525 | |
1391 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1526 | BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} } |
1392 | |
1527 | |
1393 | use AnyEvent; |
1528 | use AnyEvent; |
1394 | |
1529 | |
1395 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1530 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1396 | be used to probe what backend is used and gain other information (which |
1531 | be used to probe what backend is used and gain other information (which |
1397 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL), |
1532 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL), |
1398 | and $ENV{PERL_ANYEGENT_STRICT}. |
1533 | and $ENV{PERL_ANYEVENT_STRICT}. |
|
|
1534 | |
|
|
1535 | Note that AnyEvent will remove *all* environment variables starting with |
|
|
1536 | "PERL_ANYEVENT_" from %ENV when it is loaded while taint mode is |
|
|
1537 | enabled. |
1399 | |
1538 | |
1400 | BUGS |
1539 | BUGS |
1401 | Perl 5.8 has numerous memleaks that sometimes hit this module and are |
1540 | Perl 5.8 has numerous memleaks that sometimes hit this module and are |
1402 | hard to work around. If you suffer from memleaks, first upgrade to Perl |
1541 | hard to work around. If you suffer from memleaks, first upgrade to Perl |
1403 | 5.10 and check wether the leaks still show up. (Perl 5.10.0 has other |
1542 | 5.10 and check wether the leaks still show up. (Perl 5.10.0 has other |