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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.193 by root, Thu May 26 04:15:37 2011 UTC vs.
Revision 1.195 by root, Fri May 27 19:56:31 2011 UTC

… …
168use common::sense; 168use common::sense;
169 169
170use base 'Exporter'; 170use base 'Exporter';
171 171
172BEGIN { 172BEGIN {
173 our $VERSION = '3.8'; 173 our $VERSION = '3.9';
174 174
175 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 175 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx 176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync 177 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
178 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead 178 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
… …
368 } else { 368 } else {
369 die "open failed: $!\n"; 369 die "open failed: $!\n";
370 } 370 }
371 }; 371 };
372 372
373In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>,
374C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the
375following POSIX and non-POSIX constants are available (missing ones on
376your system are, as usual, C<0>):
377
378C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
379C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
380C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.
381
373 382
374=item aio_close $fh, $callback->($status) 383=item aio_close $fh, $callback->($status)
375 384
376Asynchronously close a file and call the callback with the result 385Asynchronously close a file and call the callback with the result
377code. 386code.
… …
1555Sets the minimum idle timeout (default 10) after which worker threads are 1564Sets the minimum idle timeout (default 10) after which worker threads are
1556allowed to exit. SEe C<IO::AIO::max_idle>. 1565allowed to exit. SEe C<IO::AIO::max_idle>.
1557 1566
1558=item IO::AIO::max_outstanding $maxreqs 1567=item IO::AIO::max_outstanding $maxreqs
1559 1568
1569Sets the maximum number of outstanding requests to C<$nreqs>. If
1570you do queue up more than this number of requests, the next call to
1571C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as
1572C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no
1573longer exceeded.
1574
1575In other words, this setting does not enforce a queue limit, but can be
1576used to make poll functions block if the limit is exceeded.
1577
1560This is a very bad function to use in interactive programs because it 1578This is a very bad function to use in interactive programs because it
1561blocks, and a bad way to reduce concurrency because it is inexact: Better 1579blocks, and a bad way to reduce concurrency because it is inexact: Better
1562use an C<aio_group> together with a feed callback. 1580use an C<aio_group> together with a feed callback.
1563 1581
1564Sets the maximum number of outstanding requests to C<$nreqs>. If you 1582It's main use is in scripts without an event loop - when you want to stat
1565do queue up more than this number of requests, the next call to the 1583a lot of files, you can write somehting like this:
1566C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1567function will block until the limit is no longer exceeded.
1568 1584
1569The default value is very large, so there is no practical limit on the 1585 IO::AIO::max_outstanding 32;
1570number of outstanding requests.
1571 1586
1572You can still queue as many requests as you want. Therefore, 1587 for my $path (...) {
1573C<max_outstanding> is mainly useful in simple scripts (with low values) or 1588 aio_stat $path , ...;
1574as a stop gap to shield against fatal memory overflow (with large values). 1589 IO::AIO::poll_cb;
1590 }
1591
1592 IO::AIO::flush;
1593
1594The call to C<poll_cb> inside the loop will normally return instantly, but
1595as soon as more thna C<32> reqeusts are in-flight, it will block until
1596some requests have been handled. This keeps the loop from pushing a large
1597number of C<aio_stat> requests onto the queue.
1598
1599The default value for C<max_outstanding> is very large, so there is no
1600practical limit on the number of outstanding requests.
1575 1601
1576=back 1602=back
1577 1603
1578=head3 STATISTICAL INFORMATION 1604=head3 STATISTICAL INFORMATION
1579 1605

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