… | |
… | |
576 | after => 1, |
576 | after => 1, |
577 | cb => sub { $result_ready->send }, |
577 | cb => sub { $result_ready->send }, |
578 | ); |
578 | ); |
579 | |
579 | |
580 | # this "blocks" (while handling events) till the callback |
580 | # this "blocks" (while handling events) till the callback |
581 | # calls -<send |
581 | # calls ->send |
582 | $result_ready->recv; |
582 | $result_ready->recv; |
583 | |
583 | |
584 | Example: wait for a timer, but take advantage of the fact that condition |
584 | Example: wait for a timer, but take advantage of the fact that condition |
585 | variables are also callable directly. |
585 | variables are also callable directly. |
586 | |
586 | |
… | |
… | |
643 | into one. For example, a function that pings many hosts in parallel |
643 | into one. For example, a function that pings many hosts in parallel |
644 | might want to use a condition variable for the whole process. |
644 | might want to use a condition variable for the whole process. |
645 | |
645 | |
646 | Every call to "->begin" will increment a counter, and every call to |
646 | Every call to "->begin" will increment a counter, and every call to |
647 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
647 | "->end" will decrement it. If the counter reaches 0 in "->end", the |
648 | (last) callback passed to "begin" will be executed. That callback is |
648 | (last) callback passed to "begin" will be executed, passing the |
649 | *supposed* to call "->send", but that is not required. If no |
649 | condvar as first argument. That callback is *supposed* to call |
|
|
650 | "->send", but that is not required. If no group callback was set, |
650 | callback was set, "send" will be called without any arguments. |
651 | "send" will be called without any arguments. |
651 | |
652 | |
652 | You can think of "$cv->send" giving you an OR condition (one call |
653 | You can think of "$cv->send" giving you an OR condition (one call |
653 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
654 | sends), while "$cv->begin" and "$cv->end" giving you an AND |
654 | condition (all "begin" calls must be "end"'ed before the condvar |
655 | condition (all "begin" calls must be "end"'ed before the condvar |
655 | sends). |
656 | sends). |
… | |
… | |
683 | that are begung can potentially be zero: |
684 | that are begung can potentially be zero: |
684 | |
685 | |
685 | my $cv = AnyEvent->condvar; |
686 | my $cv = AnyEvent->condvar; |
686 | |
687 | |
687 | my %result; |
688 | my %result; |
688 | $cv->begin (sub { $cv->send (\%result) }); |
689 | $cv->begin (sub { shift->send (\%result) }); |
689 | |
690 | |
690 | for my $host (@list_of_hosts) { |
691 | for my $host (@list_of_hosts) { |
691 | $cv->begin; |
692 | $cv->begin; |
692 | ping_host_then_call_callback $host, sub { |
693 | ping_host_then_call_callback $host, sub { |
693 | $result{$host} = ...; |
694 | $result{$host} = ...; |
… | |
… | |
771 | SUPPORTED EVENT LOOPS/BACKENDS |
772 | SUPPORTED EVENT LOOPS/BACKENDS |
772 | The available backend classes are (every class has its own manpage): |
773 | The available backend classes are (every class has its own manpage): |
773 | |
774 | |
774 | Backends that are autoprobed when no other event loop can be found. |
775 | Backends that are autoprobed when no other event loop can be found. |
775 | EV is the preferred backend when no other event loop seems to be in |
776 | EV is the preferred backend when no other event loop seems to be in |
776 | use. If EV is not installed, then AnyEvent will try Event, and, |
777 | use. If EV is not installed, then AnyEvent will fall back to its own |
777 | failing that, will fall back to its own pure-perl implementation, |
778 | pure-perl implementation, which is available everywhere as it comes |
778 | which is available everywhere as it comes with AnyEvent itself. |
779 | with AnyEvent itself. |
779 | |
780 | |
780 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
781 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
781 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
|
|
782 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
782 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
783 | |
783 | |
784 | Backends that are transparently being picked up when they are used. |
784 | Backends that are transparently being picked up when they are used. |
785 | These will be used when they are currently loaded when the first |
785 | These will be used when they are currently loaded when the first |
786 | watcher is created, in which case it is assumed that the application |
786 | watcher is created, in which case it is assumed that the application |
787 | is using them. This means that AnyEvent will automatically pick the |
787 | is using them. This means that AnyEvent will automatically pick the |
788 | right backend when the main program loads an event module before |
788 | right backend when the main program loads an event module before |
789 | anything starts to create watchers. Nothing special needs to be done |
789 | anything starts to create watchers. Nothing special needs to be done |
790 | by the main program. |
790 | by the main program. |
791 | |
791 | |
|
|
792 | AnyEvent::Impl::Event based on Event, very stable, few glitches. |
792 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
793 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
793 | AnyEvent::Impl::Tk based on Tk, very broken. |
794 | AnyEvent::Impl::Tk based on Tk, very broken. |
794 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
795 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
795 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
796 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
796 | AnyEvent::Impl::Irssi used when running within irssi. |
797 | AnyEvent::Impl::Irssi used when running within irssi. |
… | |
… | |
1032 | Event::ExecFlow |
1033 | Event::ExecFlow |
1033 | High level API for event-based execution flow control. |
1034 | High level API for event-based execution flow control. |
1034 | |
1035 | |
1035 | Coro |
1036 | Coro |
1036 | Has special support for AnyEvent via Coro::AnyEvent. |
1037 | Has special support for AnyEvent via Coro::AnyEvent. |
|
|
1038 | |
|
|
1039 | SIMPLIFIED AE API |
|
|
1040 | Starting with version 5.0, AnyEvent officially supports a second, much |
|
|
1041 | simpler, API that is designed to reduce the calling, typing and memory |
|
|
1042 | overhead. |
|
|
1043 | |
|
|
1044 | See the AE manpage for details. |
1037 | |
1045 | |
1038 | ERROR AND EXCEPTION HANDLING |
1046 | ERROR AND EXCEPTION HANDLING |
1039 | In general, AnyEvent does not do any error handling - it relies on the |
1047 | In general, AnyEvent does not do any error handling - it relies on the |
1040 | caller to do that if required. The AnyEvent::Strict module (see also the |
1048 | caller to do that if required. The AnyEvent::Strict module (see also the |
1041 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
1049 | "PERL_ANYEVENT_STRICT" environment variable, below) provides strict |
… | |
… | |
1366 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1374 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
1367 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1375 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
1368 | which it is), lets them fire exactly once and destroys them again. |
1376 | which it is), lets them fire exactly once and destroys them again. |
1369 | |
1377 | |
1370 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1378 | Source code for this benchmark is found as eg/bench in the AnyEvent |
1371 | distribution. |
1379 | distribution. It uses the AE interface, which makes a real difference |
|
|
1380 | for the EV and Perl backends only. |
1372 | |
1381 | |
1373 | Explanation of the columns |
1382 | Explanation of the columns |
1374 | *watcher* is the number of event watchers created/destroyed. Since |
1383 | *watcher* is the number of event watchers created/destroyed. Since |
1375 | different event models feature vastly different performances, each event |
1384 | different event models feature vastly different performances, each event |
1376 | loop was given a number of watchers so that overall runtime is |
1385 | loop was given a number of watchers so that overall runtime is |
… | |
… | |
1395 | *destroy* is the time, in microseconds, that it takes to destroy a |
1404 | *destroy* is the time, in microseconds, that it takes to destroy a |
1396 | single watcher. |
1405 | single watcher. |
1397 | |
1406 | |
1398 | Results |
1407 | Results |
1399 | name watchers bytes create invoke destroy comment |
1408 | name watchers bytes create invoke destroy comment |
1400 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1409 | EV/EV 100000 223 0.47 0.43 0.27 EV native interface |
1401 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1410 | EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers |
1402 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1411 | Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal |
1403 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1412 | Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation |
1404 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1413 | Event/Event 16000 516 31.16 31.84 0.82 Event native interface |
1405 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1414 | Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers |
1406 | IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll |
1415 | IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll |
1407 | IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll |
1416 | IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll |
1408 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1417 | Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour |
1409 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1418 | Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers |
1410 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1419 | POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event |
1411 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1420 | POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select |
1412 | |
1421 | |
1413 | Discussion |
1422 | Discussion |
1414 | The benchmark does *not* measure scalability of the event loop very |
1423 | The benchmark does *not* measure scalability of the event loop very |
1415 | well. For example, a select-based event loop (such as the pure perl one) |
1424 | well. For example, a select-based event loop (such as the pure perl one) |
1416 | can never compete with an event loop that uses epoll when the number of |
1425 | can never compete with an event loop that uses epoll when the number of |
… | |
… | |
1427 | benchmark machine, handling an event takes roughly 1600 CPU cycles with |
1436 | benchmark machine, handling an event takes roughly 1600 CPU cycles with |
1428 | EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 |
1437 | EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 |
1429 | CPU cycles with POE. |
1438 | CPU cycles with POE. |
1430 | |
1439 | |
1431 | "EV" is the sole leader regarding speed and memory use, which are both |
1440 | "EV" is the sole leader regarding speed and memory use, which are both |
1432 | maximal/minimal, respectively. Even when going through AnyEvent, it uses |
1441 | maximal/minimal, respectively. When using the AE API there is zero |
|
|
1442 | overhead (when going through the AnyEvent API create is about 5-6 times |
|
|
1443 | slower, with other times being equal, so still uses far less memory than |
1433 | far less memory than any other event loop and is still faster than Event |
1444 | any other event loop and is still faster than Event natively). |
1434 | natively. |
|
|
1435 | |
1445 | |
1436 | The pure perl implementation is hit in a few sweet spots (both the |
1446 | The pure perl implementation is hit in a few sweet spots (both the |
1437 | constant timeout and the use of a single fd hit optimisations in the |
1447 | constant timeout and the use of a single fd hit optimisations in the |
1438 | perl interpreter and the backend itself). Nevertheless this shows that |
1448 | perl interpreter and the backend itself). Nevertheless this shows that |
1439 | it adds very little overhead in itself. Like any select-based backend |
1449 | it adds very little overhead in itself. Like any select-based backend |
… | |
… | |
1509 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which |
1519 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which |
1510 | 100 (1%) are active. This mirrors the activity of large servers with |
1520 | 100 (1%) are active. This mirrors the activity of large servers with |
1511 | many connections, most of which are idle at any one point in time. |
1521 | many connections, most of which are idle at any one point in time. |
1512 | |
1522 | |
1513 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1523 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1514 | distribution. |
1524 | distribution. It uses the AE interface, which makes a real difference |
|
|
1525 | for the EV and Perl backends only. |
1515 | |
1526 | |
1516 | Explanation of the columns |
1527 | Explanation of the columns |
1517 | *sockets* is the number of sockets, and twice the number of "servers" |
1528 | *sockets* is the number of sockets, and twice the number of "servers" |
1518 | (as each server has a read and write socket end). |
1529 | (as each server has a read and write socket end). |
1519 | |
1530 | |
… | |
… | |
1525 | forwarding it to another server. This includes deleting the old timeout |
1536 | forwarding it to another server. This includes deleting the old timeout |
1526 | and creating a new one that moves the timeout into the future. |
1537 | and creating a new one that moves the timeout into the future. |
1527 | |
1538 | |
1528 | Results |
1539 | Results |
1529 | name sockets create request |
1540 | name sockets create request |
1530 | EV 20000 69.01 11.16 |
1541 | EV 20000 62.66 7.99 |
1531 | Perl 20000 73.32 35.87 |
1542 | Perl 20000 68.32 32.64 |
1532 | IOAsync 20000 157.00 98.14 epoll |
1543 | IOAsync 20000 174.06 101.15 epoll |
1533 | IOAsync 20000 159.31 616.06 poll |
1544 | IOAsync 20000 174.67 610.84 poll |
1534 | Event 20000 212.62 257.32 |
1545 | Event 20000 202.69 242.91 |
1535 | Glib 20000 651.16 1896.30 |
1546 | Glib 20000 557.01 1689.52 |
1536 | POE 20000 349.67 12317.24 uses POE::Loop::Event |
1547 | POE 20000 341.54 12086.32 uses POE::Loop::Event |
1537 | |
1548 | |
1538 | Discussion |
1549 | Discussion |
1539 | This benchmark *does* measure scalability and overall performance of the |
1550 | This benchmark *does* measure scalability and overall performance of the |
1540 | particular event loop. |
1551 | particular event loop. |
1541 | |
1552 | |