[ViewVC] Diff of: cvs/Linux-AIO/AIO.pm

Comparing Linux-AIO/AIO.pm (file contents):
Revision 1.8 by root, Tue Dec 25 02:33:48 2001 UTC vs.
Revision 1.24 by root, Wed Jun 29 15:28:14 2005 UTC

…		…
6		6
7	use Linux::AIO;	7	use Linux::AIO;
8		8
9	=head1 DESCRIPTION	9	=head1 DESCRIPTION
10		10
11	This module implements asynchroneous i/o using the means available to	11	This module implements asynchronous i/o using the means available to linux
12	linux - clone. It does not hook into the POSIX aio_* functions because	12	- clone. It does not hook into the POSIX aio_* functions because linux
13	linux does not yet support these in the kernel. Instead, a number of	13	does not yet support these in the kernel (and even if, it would only allow
14	threads are started that execute your read/writes and signal their	14	aio_read and write, not open and stat).
15	completion.	15
		16	Instead, in this module a number of (non-posix) threads are started that
		17	execute your read/writes and signal their completion. You don't need
		18	thread support in your libc or perl, and the threads created by this
		19	module will not be visible to the pthreads library.
		20
		21	NOTICE: the threads created by this module will automatically be killed
		22	when the thread calling min_parallel exits. Make sure you only ever call
		23	min_parallel from the same thread that loaded this module.
		24
		25	Although the module will work with threads, it is not reentrant, so use
		26	appropriate locking yourself.
16		27
17	=over 4	28	=over 4
18		29
19	=cut	30	=cut
20		31
21	package Linux::AIO;	32	package Linux::AIO;
22		33
23	use base 'Exporter';	34	use base 'Exporter';
24		35
25	BEGIN {	36	BEGIN {
26	$VERSION = 0.011;	37	$VERSION = 1.5;
27		38
28	@EXPORT = qw(aio_read aio_write aio_open aio_close);	39	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink);
29	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel nreqs);	40	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel nreqs);
30		41
31	require XSLoader;	42	require XSLoader;
32	XSLoader::load Linux::AIO, $VERSION;	43	XSLoader::load Linux::AIO, $VERSION;
33	}	44	}
34		45
35	=item Linux::AIO::min_parallel($nthreads)	46	=item Linux::AIO::min_parallel $nthreads
36		47
37	Set the minimum number of AIO threads to $nthreads. You I<have> to call	48	Set the minimum number of AIO threads to C<$nthreads>. The default is
38	this function with a positive number at leats once, otherwise no threads	49	C<1>, which means a single asynchronous operation can be done at one time
39	will be started and you aio-operations will seem to hang.	50	(the number of outstanding operations, however, is unlimited).
		51
		52	It is recommended to keep the number of threads low, as some linux
		53	kernel versions will scale negatively with the number of threads (higher
		54	parallelity => MUCH higher latency).
		55
		56	=item Linux::AIO::max_parallel $nthreads
		57
		58	Sets the maximum number of AIO threads to C<$nthreads>. If more than
		59	the specified number of threads are currently running, kill them. This
		60	function blocks until the limit is reached.
		61
		62	This module automatically runs C<max_parallel 0> at program end, to ensure
		63	that all threads are killed and that there are no outstanding requests.
40		64
41	=item $fileno = Linux::AIO::poll_fileno	65	=item $fileno = Linux::AIO::poll_fileno
42		66
43	Return the request result pipe filehandle. This filehandle must be polled	67	Return the I<request result pipe filehandle>. This filehandle must be
44	for reading. If the pipe becomes readable you have to call C<poll_cb>.	68	polled for reading by some mechanism outside this module (e.g. Event
		69	or select, see below). If the pipe becomes readable you have to call
		70	C<poll_cb> to check the results.
45		71
46	=item Linux::AIO::poll_cb	72	=item Linux::AIO::poll_cb
47		73
48	Process all outstanding events on the result pipe. You have to call this	74	Process all outstanding events on the result pipe. You have to call this
49	regularly. Returns the number of events processed.	75	regularly. Returns the number of events processed. Returns immediately
		76	when no events are outstanding.
50		77
51	You can use Event to multiplex, e.g.:	78	You can use Event to multiplex, e.g.:
52		79
53	Event->io(fd => Linux::AIO::poll_fileno,	80	Event->io (fd => Linux::AIO::poll_fileno,
54	poll => 'r', async => 1,	81	poll => 'r', async => 1,
55	cb => \&Linux::AIO::poll_cb );	82	cb => \&Linux::AIO::poll_cb );
56		83
		84	=item Linux::AIO::poll_wait
		85
		86	Wait till the result filehandle becomes ready for reading (simply does a
		87	select on the filehandle. This is useful if you want to synchronously wait
		88	for some requests to finish).
57		89
58	=item Linux::AIO::nreqs	90	=item Linux::AIO::nreqs
59		91
60	Returns the number of requests currently outstanding.	92	Returns the number of requests currently outstanding.
61		93
		94	=item aio_open $pathname, $flags, $mode, $callback
		95
		96	Asynchronously open or create a file and call the callback with the
		97	filedescriptor (NOT a perl filehandle, sorry for that, but watch out, this
		98	might change in the future).
		99
		100	=item aio_close $fh, $callback
		101
		102	Asynchronously close a file and call the callback with the result code.
		103
62	=item aio_read($fh,$offset,$length, $data,$dataoffset,$callback)	104	=item aio_read $fh,$offset,$length, $data,$dataoffset,$callback
		105
63	aio_write($fh,$offset,$length, $data,$dataoffset,$callback)	106	=item aio_write $fh,$offset,$length, $data,$dataoffset,$callback
64		107
65	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	108	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
66	into the scalar given by C<data> and offset C<dataoffset> and calls the	109	into the scalar given by C<data> and offset C<dataoffset> and calls the
67	callback without the actual number of bytes read (or undef on error).	110	callback without the actual number of bytes read (or C<undef> on error).
68		111
69	=item aio_open($pathname, $flags, $mode, $callback)	112	=item aio_stat $fh_or_path, $callback
70		113
71	Asynchronously open or create a file and call the callback with the	114	=item aio_lstat $fh, $callback
72	filedescriptor.
73		115
74	=item aio_close($fh, $callback)	116	Works like perl's C<stat> or C<lstat> in void context. The callback will
		117	be called after the stat and the results will be available using C<stat _>
		118	or C<-s _> etc...
75		119
76	Asynchronously close a file and call the callback with the result code.	120	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
		121	error when stat'ing a large file, the results will be silently truncated
		122	unless perl itself is compiled with large file support.
		123
		124	=item aio_unlink $pathname, $callback
		125
		126	Asynchronously unlink a file.
77		127
78	=cut	128	=cut
		129
		130	min_parallel 1;
79		131
80	END {	132	END {
81	max_parallel 0;	133	max_parallel 0;
82	}	134	}
83		135
…		…
85		137
86	=back	138	=back
87		139
88	=head1 BUGS	140	=head1 BUGS
89		141
90	This module has not yet been extensively tested. Watch out!	142	This module has been extensively tested in a large and very busy webserver
		143	for many years now.
91		144
92	- aio_stat/lstat are seriously missing here.	145	- aio_open gives a fd, but all other functions expect a perl filehandle.
93		146
94	=head1 SEE ALSO	147	=head1 SEE ALSO
95		148
96	L<Coro>.	149	L<Coro>.
97		150
98	=head1 AUTHOR	151	=head1 AUTHOR
99		152
100	Marc Lehmann <pcg@goof.com>	153	Marc Lehmann <schmorp@schmorp.de>
101	http://www.goof.com/pcg/marc/	154	http://home.schmorp.de/
102		155
103	=cut	156	=cut
104		157

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Comparing Linux-AIO/AIO.pm (file contents): Revision 1.8 by root, Tue Dec 25 02:33:48 2001 UTC vs. Revision 1.24 by root, Wed Jun 29 15:28:14 2005 UTC

Diff Legend

Comparing Linux-AIO/AIO.pm (file contents):
Revision 1.8 by root, Tue Dec 25 02:33:48 2001 UTC vs.
Revision 1.24 by root, Wed Jun 29 15:28:14 2005 UTC