| … | |
… | |
| 136 | |
136 | |
| 137 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
137 | Note that C<my $w; $w => combination. This is necessary because in Perl, |
| 138 | my variables are only visible after the statement in which they are |
138 | my variables are only visible after the statement in which they are |
| 139 | declared. |
139 | declared. |
| 140 | |
140 | |
| 141 | =head2 IO WATCHERS |
141 | =head2 I/O WATCHERS |
| 142 | |
142 | |
| 143 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
143 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
| 144 | with the following mandatory key-value pairs as arguments: |
144 | with the following mandatory key-value pairs as arguments: |
| 145 | |
145 | |
| 146 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for |
146 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for |
| … | |
… | |
| 706 | |
706 | |
| 707 | =back |
707 | =back |
| 708 | |
708 | |
| 709 | =head1 EXAMPLE PROGRAM |
709 | =head1 EXAMPLE PROGRAM |
| 710 | |
710 | |
| 711 | The following program uses an IO watcher to read data from STDIN, a timer |
711 | The following program uses an I/O watcher to read data from STDIN, a timer |
| 712 | to display a message once per second, and a condition variable to quit the |
712 | to display a message once per second, and a condition variable to quit the |
| 713 | program when the user enters quit: |
713 | program when the user enters quit: |
| 714 | |
714 | |
| 715 | use AnyEvent; |
715 | use AnyEvent; |
| 716 | |
716 | |
| … | |
… | |
| 867 | |
867 | |
| 868 | To give you an idea of the performance and overheads that AnyEvent adds |
868 | To give you an idea of the performance and overheads that AnyEvent adds |
| 869 | over the event loops themselves (and to give you an impression of the |
869 | over the event loops themselves (and to give you an impression of the |
| 870 | speed of various event loops), here is a benchmark of various supported |
870 | speed of various event loops), here is a benchmark of various supported |
| 871 | event models natively and with anyevent. The benchmark creates a lot of |
871 | event models natively and with anyevent. The benchmark creates a lot of |
| 872 | timers (with a zero timeout) and io watchers (watching STDOUT, a pty, to |
872 | timers (with a zero timeout) and I/O watchers (watching STDOUT, a pty, to |
| 873 | become writable, which it is), lets them fire exactly once and destroys |
873 | become writable, which it is), lets them fire exactly once and destroys |
| 874 | them again. |
874 | them again. |
| 875 | |
875 | |
| 876 | Rewriting the benchmark to use many different sockets instead of using |
876 | Rewriting the benchmark to use many different sockets instead of using |
| 877 | the same filehandle for all io watchers results in a much longer runtime |
877 | the same filehandle for all I/O watchers results in a much longer runtime |
| 878 | (socket creation is expensive), but qualitatively the same figures, so it |
878 | (socket creation is expensive), but qualitatively the same figures, so it |
| 879 | was not used. |
879 | was not used. |
| 880 | |
880 | |
| 881 | =head2 Explanation of the columns |
881 | =head2 Explanation of the columns |
| 882 | |
882 | |
| … | |
… | |
| 962 | |
962 | |
| 963 | C<POE>, regardless of underlying event loop (wether using its pure perl |
963 | C<POE>, regardless of underlying event loop (wether using its pure perl |
| 964 | select-based backend or the Event module) shows abysmal performance and |
964 | select-based backend or the Event module) shows abysmal performance and |
| 965 | memory usage: Watchers use almost 30 times as much memory as EV watchers, |
965 | memory usage: Watchers use almost 30 times as much memory as EV watchers, |
| 966 | and 10 times as much memory as both Event or EV via AnyEvent. Watcher |
966 | and 10 times as much memory as both Event or EV via AnyEvent. Watcher |
| 967 | invocation is almost 700 times slower than with AnyEvent's pure perl |
967 | invocation is almost 900 times slower than with AnyEvent's pure perl |
| 968 | implementation. The design of the POE adaptor class in AnyEvent can not |
968 | implementation. The design of the POE adaptor class in AnyEvent can not |
| 969 | really account for this, as session creation overhead is small compared |
969 | really account for this, as session creation overhead is small compared |
| 970 | to execution of the state machine, which is coded pretty optimally within |
970 | to execution of the state machine, which is coded pretty optimally within |
| 971 | L<AnyEvent::Impl::POE>. POE simply seems to be abysmally slow. |
971 | L<AnyEvent::Impl::POE>. POE simply seems to be abysmally slow. |
| 972 | |
972 | |
