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=head1 NAME |
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Linux::AIO - linux-specific aio implemented using clone |
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=head1 SYNOPSIS |
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use Linux::AIO; |
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=head1 DESCRIPTION |
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|
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This module implements asynchroneous i/o using the means available to |
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linux - clone. It does not hook into the POSIX aio_* functions because |
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linux does not yet support these in the kernel. Instead, a number of |
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threads are started that execute your read/writes and signal their |
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completion. |
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=over 4 |
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=cut |
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|
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package Linux::AIO; |
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use base 'Exporter'; |
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|
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BEGIN { |
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$VERSION = 0.011; |
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|
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@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat); |
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@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel nreqs); |
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|
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require XSLoader; |
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XSLoader::load Linux::AIO, $VERSION; |
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} |
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=item Linux::AIO::min_parallel($nthreads) |
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Set the minimum number of AIO threads to $nthreads. You I<have> to call |
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this function with a positive number at leats once, otherwise no threads |
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will be started and you aio-operations will seem to hang. |
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|
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=item $fileno = Linux::AIO::poll_fileno |
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|
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Return the request result pipe filehandle. This filehandle must be polled |
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for reading. If the pipe becomes readable you have to call C<poll_cb>. |
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=item Linux::AIO::poll_cb |
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Process all outstanding events on the result pipe. You have to call this |
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regularly. Returns the number of events processed. |
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|
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You can use Event to multiplex, e.g.: |
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|
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Event->io(fd => Linux::AIO::poll_fileno, |
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poll => 'r', async => 1, |
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cb => \&Linux::AIO::poll_cb ); |
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|
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|
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=item Linux::AIO::nreqs |
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Returns the number of requests currently outstanding. |
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=item aio_open($pathname, $flags, $mode, $callback) |
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Asynchronously open or create a file and call the callback with the |
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filedescriptor. |
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=item aio_close($fh, $callback) |
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Asynchronously close a file and call the callback with the result code. |
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=item aio_read($fh,$offset,$length, $data,$dataoffset,$callback) |
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=item aio_write($fh,$offset,$length, $data,$dataoffset,$callback) |
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Reads or writes C<length> bytes from the specified C<fh> and C<offset> |
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into the scalar given by C<data> and offset C<dataoffset> and calls the |
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callback without the actual number of bytes read (or undef on error). |
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|
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=item aio_stat($fh_or_path,$callback) |
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=item aio_lstat($fh,$callback) |
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Works like perl's C<stat> or C<lstat> in void context, i.e. the callback |
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will be called after the stat and the results will be available using |
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C<stat _> or C<-s _> etc... |
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|
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Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
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error when stat'ing a large file, the results will be silently truncated |
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unless perl itself is compiled with large file support. |
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|
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=cut |
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|
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END { |
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max_parallel 0; |
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} |
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1; |
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=back |
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|
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=head1 BUGS |
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This module has not yet been extensively tested. Watch out! |
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- aio_stat/lstat are seriously missing here. |
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=head1 SEE ALSO |
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|
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L<Coro>. |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <pcg@goof.com> |
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http://www.goof.com/pcg/marc/ |
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|
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=cut |
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