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

Comparing Linux-AIO/AIO.pm (file contents):
Revision 1.3 by root, Tue Aug 14 23:25:39 2001 UTC vs.
Revision 1.21 by root, Sat Jan 15 00:05:14 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 = 0.001;	37	$VERSION = 1.4;
27		38
28	@EXPORT = qw(aio_read aio_write);	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).
40		51
41	=cut	52	It is recommended to keep the number of threads low, as many linux
42		53	kernel versions will scale negatively with the number of threads (higher
43	=item aio_read($fh,$offset,$length, $data,$dataoffset,$callback)	54	parallelity => MUCH higher latency).
44	aio_write($fh,$offset,$length, $data,$dataoffset,$callback)
45
46	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
47	into the scalar given by C<data> and offset C<dataoffset> and calls the
48	callback without the actual number of bytes read (or undef on error).
49		55
50	=item $fileno = Linux::AIO::poll_fileno	56	=item $fileno = Linux::AIO::poll_fileno
51		57
52	Return the request result pipe filehandle. This filehandle must be polled	58	Return the I<request result pipe filehandle>. This filehandle must be
53	for reading. If the pipe becomes readable you have to call C<poll_cb>.	59	polled for reading by some mechanism outside this module (e.g. Event
		60	or select, see below). If the pipe becomes readable you have to call
		61	C<poll_cb> to check the results.
54		62
55	=item Linux::AIO::poll_cb	63	=item Linux::AIO::poll_cb
56		64
57	Process all outstanding events on the result pipe. You have to call this	65	Process all outstanding events on the result pipe. You have to call this
58	regularly. Returns the number of events processed.	66	regularly. Returns the number of events processed. Returns immediately
		67	when no events are outstanding.
59		68
60	You can use Event to multiplex, e.g.:	69	You can use Event to multiplex, e.g.:
61		70
62	Event->io(fd => Linux::AIO::poll_fileno,	71	Event->io (fd => Linux::AIO::poll_fileno,
63	poll => 'r', async => 1,	72	poll => 'r', async => 1,
64	cb => \&Linux::AIO::poll_cb );	73	cb => \&Linux::AIO::poll_cb );
65		74
66		75
67	=item Linux::AIO::nreqs	76	=item Linux::AIO::nreqs
68		77
69	Returns the number of requests currently outstanding.	78	Returns the number of requests currently outstanding.
70		79
		80	=item aio_open $pathname, $flags, $mode, $callback
		81
		82	Asynchronously open or create a file and call the callback with the
		83	filedescriptor (NOT a perl filehandle, sorry for that, but watch out, this
		84	might change in the future).
		85
		86	=item aio_close $fh, $callback
		87
		88	Asynchronously close a file and call the callback with the result code.
		89
		90	=item aio_read $fh,$offset,$length, $data,$dataoffset,$callback
		91
		92	=item aio_write $fh,$offset,$length, $data,$dataoffset,$callback
		93
		94	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
		95	into the scalar given by C<data> and offset C<dataoffset> and calls the
		96	callback without the actual number of bytes read (or C<undef> on error).
		97
		98	=item aio_stat $fh_or_path, $callback
		99
		100	=item aio_lstat $fh, $callback
		101
		102	Works like perl's C<stat> or C<lstat> in void context. The callback will
		103	be called after the stat and the results will be available using C<stat _>
		104	or C<-s _> etc...
		105
		106	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
		107	error when stat'ing a large file, the results will be silently truncated
		108	unless perl itself is compiled with large file support.
		109
		110	=item aio_unlink $pathname, $callback
		111
		112	Asynchronously unlink a file.
		113
71	=cut	114	=cut
		115
		116	min_parallel 1;
72		117
73	END {	118	END {
74	max_parallel 0;	119	max_parallel 0;
75	}	120	}
76		121
…		…
78		123
79	=back	124	=back
80		125
81	=head1 BUGS	126	=head1 BUGS
82		127
83	This module has not yet been extensively tested. Watch out!	128	This module has been extensively tested in a large and very busy webserver
		129	for many years now.
		130
		131	- aio_open gives a fd, but all other functions expect a perl filehandle.
84		132
85	=head1 SEE ALSO	133	=head1 SEE ALSO
86		134
87	L<Coro>.	135	L<Coro>.
88		136
89	=head1 AUTHOR	137	=head1 AUTHOR
90		138
91	Marc Lehmann <pcg@goof.com>	139	Marc Lehmann <pcg@goof.com>
92	http://www.goof.com/pcg/marc/	140	http://home.schmorp.de/
93		141
94	=cut	142	=cut
95		143

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Comparing Linux-AIO/AIO.pm (file contents): Revision 1.3 by root, Tue Aug 14 23:25:39 2001 UTC vs. Revision 1.21 by root, Sat Jan 15 00:05:14 2005 UTC

Diff Legend

Comparing Linux-AIO/AIO.pm (file contents):
Revision 1.3 by root, Tue Aug 14 23:25:39 2001 UTC vs.
Revision 1.21 by root, Sat Jan 15 00:05:14 2005 UTC