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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.67 by root, Tue Oct 24 02:25:16 2006 UTC vs.
Revision 1.68 by root, Tue Oct 24 03:17:39 2006 UTC

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18 }; 18 };
19 19
20 # version 2+ has request and group objects 20 # version 2+ has request and group objects
21 use IO::AIO 2; 21 use IO::AIO 2;
22 22
23 aioreq_pri 4; # give next request a very high priority
23 my $req = aio_unlink "/tmp/file", sub { }; 24 my $req = aio_unlink "/tmp/file", sub { };
24 $req->cancel; # cancel request if still in queue 25 $req->cancel; # cancel request if still in queue
25 26
26 my $grp = aio_group sub { print "all stats done\n" }; 27 my $grp = aio_group sub { print "all stats done\n" };
27 add $grp aio_stat "..." for ...; 28 add $grp aio_stat "..." for ...;
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59on many operating systems. However, they are often not well-supported 60on many operating systems. However, they are often not well-supported
60(Linux doesn't allow them on normal files currently, for example), 61(Linux doesn't allow them on normal files currently, for example),
61and they would only support aio_read and aio_write, so the remaining 62and they would only support aio_read and aio_write, so the remaining
62functionality would have to be implemented using threads anyway. 63functionality would have to be implemented using threads anyway.
63 64
64Although the module will work with in the presence of other threads, it is 65Although the module will work with in the presence of other threads,
65currently not reentrant, so use appropriate locking yourself, always call 66it is currently not reentrant in any way, so use appropriate locking
66C<poll_cb> from within the same thread, or never call C<poll_cb> (or other 67yourself, always call C<poll_cb> from within the same thread, or never
67C<aio_> functions) recursively. 68call C<poll_cb> (or other C<aio_> functions) recursively.
68 69
69=cut 70=cut
70 71
71package IO::AIO; 72package IO::AIO;
72 73
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122your pathnames to the locale (or other) encoding in effect in the user 123your pathnames to the locale (or other) encoding in effect in the user
123environment, d) use Glib::filename_from_unicode on unicode filenames or e) 124environment, d) use Glib::filename_from_unicode on unicode filenames or e)
124use something else. 125use something else.
125 126
126=over 4 127=over 4
128
129=item aioreq_pri $pri
130
131Sets the priority for the next aio request. The default priority
132is C<0>, the minimum and maximum priorities are C<-4> and C<4>,
133respectively. Requests with higher priority will be serviced first.
134
135The priority will be reset to C<0> after each call to one of the C<aio_>
136functions.
127 137
128=item aio_open $pathname, $flags, $mode, $callback->($fh) 138=item aio_open $pathname, $flags, $mode, $callback->($fh)
129 139
130Asynchronously open or create a file and call the callback with a newly 140Asynchronously open or create a file and call the callback with a newly
131created filehandle for the file. 141created filehandle for the file.
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681example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> 691example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>
682requests, delaying any later requests for a long time. 692requests, delaying any later requests for a long time.
683 693
684To avoid this, and allow incremental generation of requests, you can 694To avoid this, and allow incremental generation of requests, you can
685instead a group and set a feeder on it that generates those requests. The 695instead a group and set a feeder on it that generates those requests. The
686feed callback will be called whenever there are few enough (see C<feed_limit>, 696feed callback will be called whenever there are few enough (see C<limit>,
687below) requests active in the group itself and is expected to queue more 697below) requests active in the group itself and is expected to queue more
688requests. 698requests.
689 699
690The feed can queue as many requests as it likes (i.e. C<add> does not 700The feed callback can queue as many requests as it likes (i.e. C<add> does
691impose any limits). 701not impose any limits).
692 702
693If the feed does not queue more requests when called, it will be 703If the feed does not queue more requests when called, it will be
694automatically removed from the group. 704automatically removed from the group.
695 705
696If the feed limit is C<0>, it will be set to C<2> automatically. 706If the feed limit is C<0>, it will be set to C<2> automatically.
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698Example: 708Example:
699 709
700 # stat all files in @files, but only ever use four aio requests concurrently: 710 # stat all files in @files, but only ever use four aio requests concurrently:
701 711
702 my $grp = aio_group sub { print "finished\n" }; 712 my $grp = aio_group sub { print "finished\n" };
703 feed_limit $grp 4; 713 limit $grp 4;
704 feed $grp sub { 714 feed $grp sub {
705 my $file = pop @files 715 my $file = pop @files
706 or return; 716 or return;
707 717
708 add $grp aio_stat $file, sub { ... }; 718 add $grp aio_stat $file, sub { ... };
709 }; 719 };
710 720
711=item feed_limit $grp $num 721=item limit $grp $num
712 722
713Sets the feeder limit for the group: The feeder will be called whenever 723Sets the feeder limit for the group: The feeder will be called whenever
714the group contains less than this many requests. 724the group contains less than this many requests.
715 725
716Setting the limit to C<0> will pause the feeding process. 726Setting the limit to C<0> will pause the feeding process.
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886Each thread needs a stack area which is usually around 16k, sometimes much 896Each thread needs a stack area which is usually around 16k, sometimes much
887larger, depending on the OS. 897larger, depending on the OS.
888 898
889=head1 SEE ALSO 899=head1 SEE ALSO
890 900
891L<Coro>, L<Linux::AIO> (obsolete). 901L<Coro::AIO>.
892 902
893=head1 AUTHOR 903=head1 AUTHOR
894 904
895 Marc Lehmann <schmorp@schmorp.de> 905 Marc Lehmann <schmorp@schmorp.de>
896 http://home.schmorp.de/ 906 http://home.schmorp.de/

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