… | |
… | |
5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
6 | |
6 | |
7 | use IO::AIO; |
7 | use IO::AIO; |
8 | |
8 | |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
10 | my ($fh) = @_; |
10 | my $fh = shift |
|
|
11 | or die "/etc/passwd: $!"; |
11 | ... |
12 | ... |
12 | }; |
13 | }; |
13 | |
14 | |
14 | aio_unlink "/tmp/file", sub { }; |
15 | aio_unlink "/tmp/file", sub { }; |
15 | |
16 | |
… | |
… | |
61 | etc.), but can also be used to easily do operations in parallel that are |
62 | etc.), but can also be used to easily do operations in parallel that are |
62 | normally done sequentially, e.g. stat'ing many files, which is much faster |
63 | normally done sequentially, e.g. stat'ing many files, which is much faster |
63 | on a RAID volume or over NFS when you do a number of stat operations |
64 | on a RAID volume or over NFS when you do a number of stat operations |
64 | concurrently. |
65 | concurrently. |
65 | |
66 | |
66 | While this works on all types of file descriptors (for example sockets), |
67 | While most of this works on all types of file descriptors (for example |
67 | using these functions on file descriptors that support nonblocking |
68 | sockets), using these functions on file descriptors that support |
68 | operation (again, sockets, pipes etc.) is very inefficient. Use an event |
69 | nonblocking operation (again, sockets, pipes etc.) is very inefficient or |
|
|
70 | might not work (aio_read fails on sockets/pipes/fifos). Use an event loop |
69 | loop for that (such as the L<Event|Event> module): IO::AIO will naturally |
71 | for that (such as the L<Event|Event> module): IO::AIO will naturally fit |
70 | fit into such an event loop itself. |
72 | into such an event loop itself. |
71 | |
73 | |
72 | In this version, a number of threads are started that execute your |
74 | In this version, a number of threads are started that execute your |
73 | requests and signal their completion. You don't need thread support |
75 | requests and signal their completion. You don't need thread support |
74 | in perl, and the threads created by this module will not be visible |
76 | in perl, and the threads created by this module will not be visible |
75 | to perl. In the future, this module might make use of the native aio |
77 | to perl. In the future, this module might make use of the native aio |
… | |
… | |
82 | Although the module will work with in the presence of other (Perl-) |
84 | Although the module will work with in the presence of other (Perl-) |
83 | threads, it is currently not reentrant in any way, so use appropriate |
85 | threads, it is currently not reentrant in any way, so use appropriate |
84 | locking yourself, always call C<poll_cb> from within the same thread, or |
86 | locking yourself, always call C<poll_cb> from within the same thread, or |
85 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
87 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
86 | |
88 | |
|
|
89 | =head2 EXAMPLE |
|
|
90 | |
|
|
91 | This is a simple example that uses the Event module and loads |
|
|
92 | F</etc/passwd> asynchronously: |
|
|
93 | |
|
|
94 | use Fcntl; |
|
|
95 | use Event; |
|
|
96 | use IO::AIO; |
|
|
97 | |
|
|
98 | # register the IO::AIO callback with Event |
|
|
99 | Event->io (fd => IO::AIO::poll_fileno, |
|
|
100 | poll => 'r', |
|
|
101 | cb => \&IO::AIO::poll_cb); |
|
|
102 | |
|
|
103 | # queue the request to open /etc/passwd |
|
|
104 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
|
|
105 | my $fh = shift |
|
|
106 | or die "error while opening: $!"; |
|
|
107 | |
|
|
108 | # stat'ing filehandles is generally non-blocking |
|
|
109 | my $size = -s $fh; |
|
|
110 | |
|
|
111 | # queue a request to read the file |
|
|
112 | my $contents; |
|
|
113 | aio_read $fh, 0, $size, $contents, 0, sub { |
|
|
114 | $_[0] == $size |
|
|
115 | or die "short read: $!"; |
|
|
116 | |
|
|
117 | close $fh; |
|
|
118 | |
|
|
119 | # file contents now in $contents |
|
|
120 | print $contents; |
|
|
121 | |
|
|
122 | # exit event loop and program |
|
|
123 | Event::unloop; |
|
|
124 | }; |
|
|
125 | }; |
|
|
126 | |
|
|
127 | # possibly queue up other requests, or open GUI windows, |
|
|
128 | # check for sockets etc. etc. |
|
|
129 | |
|
|
130 | # process events as long as there are some: |
|
|
131 | Event::loop; |
|
|
132 | |
87 | =head1 REQUEST ANATOMY AND LIFETIME |
133 | =head1 REQUEST ANATOMY AND LIFETIME |
88 | |
134 | |
89 | Every C<aio_*> function creates a request. which is a C data structure not |
135 | Every C<aio_*> function creates a request. which is a C data structure not |
90 | directly visible to Perl. |
136 | directly visible to Perl. |
91 | |
137 | |
… | |
… | |
132 | Request has reached the end of its lifetime and holds no resources anymore |
178 | Request has reached the end of its lifetime and holds no resources anymore |
133 | (except possibly for the Perl object, but its connection to the actual |
179 | (except possibly for the Perl object, but its connection to the actual |
134 | aio request is severed and calling its methods will either do nothing or |
180 | aio request is severed and calling its methods will either do nothing or |
135 | result in a runtime error). |
181 | result in a runtime error). |
136 | |
182 | |
|
|
183 | =back |
|
|
184 | |
137 | =cut |
185 | =cut |
138 | |
186 | |
139 | package IO::AIO; |
187 | package IO::AIO; |
140 | |
188 | |
141 | no warnings; |
189 | no warnings; |
142 | use strict 'vars'; |
190 | use strict 'vars'; |
143 | |
191 | |
144 | use base 'Exporter'; |
192 | use base 'Exporter'; |
145 | |
193 | |
146 | BEGIN { |
194 | BEGIN { |
147 | our $VERSION = '2.0'; |
195 | our $VERSION = '2.3'; |
148 | |
196 | |
149 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
197 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
150 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
198 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
151 | aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move |
199 | aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link |
152 | aio_copy aio_group aio_nop aio_mknod); |
200 | aio_move aio_copy aio_group aio_nop aio_mknod); |
153 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
201 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); |
154 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
202 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
155 | min_parallel max_parallel nreqs nready npending); |
203 | min_parallel max_parallel max_idle |
|
|
204 | nreqs nready npending nthreads |
|
|
205 | max_poll_time max_poll_reqs); |
156 | |
206 | |
157 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
207 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
158 | |
208 | |
159 | require XSLoader; |
209 | require XSLoader; |
160 | XSLoader::load ("IO::AIO", $VERSION); |
210 | XSLoader::load ("IO::AIO", $VERSION); |
161 | } |
211 | } |
162 | |
212 | |
163 | =head1 FUNCTIONS |
213 | =head1 FUNCTIONS |
164 | |
214 | |
165 | =head2 AIO FUNCTIONS |
215 | =head2 AIO REQUEST FUNCTIONS |
166 | |
216 | |
167 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
217 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
168 | with the same name (sans C<aio_>). The arguments are similar or identical, |
218 | with the same name (sans C<aio_>). The arguments are similar or identical, |
169 | and they all accept an additional (and optional) C<$callback> argument |
219 | and they all accept an additional (and optional) C<$callback> argument |
170 | which must be a code reference. This code reference will get called with |
220 | which must be a code reference. This code reference will get called with |
… | |
… | |
173 | syscall has been executed asynchronously. |
223 | syscall has been executed asynchronously. |
174 | |
224 | |
175 | All functions expecting a filehandle keep a copy of the filehandle |
225 | All functions expecting a filehandle keep a copy of the filehandle |
176 | internally until the request has finished. |
226 | internally until the request has finished. |
177 | |
227 | |
178 | All requests return objects of type L<IO::AIO::REQ> that allow further |
228 | All functions return request objects of type L<IO::AIO::REQ> that allow |
179 | manipulation of those requests while they are in-flight. |
229 | further manipulation of those requests while they are in-flight. |
180 | |
230 | |
181 | The pathnames you pass to these routines I<must> be absolute and |
231 | The pathnames you pass to these routines I<must> be absolute and |
182 | encoded in byte form. The reason for the former is that at the time the |
232 | encoded as octets. The reason for the former is that at the time the |
183 | request is being executed, the current working directory could have |
233 | request is being executed, the current working directory could have |
184 | changed. Alternatively, you can make sure that you never change the |
234 | changed. Alternatively, you can make sure that you never change the |
185 | current working directory. |
235 | current working directory anywhere in the program and then use relative |
|
|
236 | paths. |
186 | |
237 | |
187 | To encode pathnames to byte form, either make sure you either: a) |
238 | To encode pathnames as octets, either make sure you either: a) always pass |
188 | always pass in filenames you got from outside (command line, readdir |
239 | in filenames you got from outside (command line, readdir etc.) without |
189 | etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
240 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
190 | your pathnames to the locale (or other) encoding in effect in the user |
241 | your pathnames to the locale (or other) encoding in effect in the user |
191 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
242 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
192 | use something else. |
243 | use something else to ensure your scalar has the correct contents. |
|
|
244 | |
|
|
245 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
|
|
246 | handles correctly wether it is set or not. |
193 | |
247 | |
194 | =over 4 |
248 | =over 4 |
195 | |
249 | |
196 | =item $prev_pri = aioreq_pri [$pri] |
250 | =item $prev_pri = aioreq_pri [$pri] |
197 | |
251 | |
… | |
… | |
220 | }; |
274 | }; |
221 | |
275 | |
222 | =item aioreq_nice $pri_adjust |
276 | =item aioreq_nice $pri_adjust |
223 | |
277 | |
224 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
278 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
225 | priority, so effects are cumulative. |
279 | priority, so the effect is cumulative. |
226 | |
280 | |
227 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
281 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
228 | |
282 | |
229 | Asynchronously open or create a file and call the callback with a newly |
283 | Asynchronously open or create a file and call the callback with a newly |
230 | created filehandle for the file. |
284 | created filehandle for the file. |
… | |
… | |
347 | Asynchronously unlink (delete) a file and call the callback with the |
401 | Asynchronously unlink (delete) a file and call the callback with the |
348 | result code. |
402 | result code. |
349 | |
403 | |
350 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
404 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
351 | |
405 | |
|
|
406 | [EXPERIMENTAL] |
|
|
407 | |
352 | Asynchronously create a device node (or fifo). See mknod(2). |
408 | Asynchronously create a device node (or fifo). See mknod(2). |
353 | |
409 | |
354 | The only portable (POSIX) way of calling this function is: |
410 | The only (POSIX-) portable way of calling this function is: |
355 | |
411 | |
356 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
412 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
357 | |
413 | |
358 | =item aio_link $srcpath, $dstpath, $callback->($status) |
414 | =item aio_link $srcpath, $dstpath, $callback->($status) |
359 | |
415 | |
… | |
… | |
362 | |
418 | |
363 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
419 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
364 | |
420 | |
365 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
421 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
366 | the path C<$dstpath> and call the callback with the result code. |
422 | the path C<$dstpath> and call the callback with the result code. |
|
|
423 | |
|
|
424 | =item aio_readlink $path, $callback->($link) |
|
|
425 | |
|
|
426 | Asynchronously read the symlink specified by C<$path> and pass it to |
|
|
427 | the callback. If an error occurs, nothing or undef gets passed to the |
|
|
428 | callback. |
367 | |
429 | |
368 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
430 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
369 | |
431 | |
370 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
432 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
371 | rename(2) and call the callback with the result code. |
433 | rename(2) and call the callback with the result code. |
… | |
… | |
400 | errors are being ignored. |
462 | errors are being ignored. |
401 | |
463 | |
402 | =cut |
464 | =cut |
403 | |
465 | |
404 | sub aio_copy($$;$) { |
466 | sub aio_copy($$;$) { |
|
|
467 | aio_block { |
405 | my ($src, $dst, $cb) = @_; |
468 | my ($src, $dst, $cb) = @_; |
406 | |
469 | |
407 | my $pri = aioreq_pri; |
470 | my $pri = aioreq_pri; |
408 | my $grp = aio_group $cb; |
471 | my $grp = aio_group $cb; |
409 | |
472 | |
410 | aioreq_pri $pri; |
473 | aioreq_pri $pri; |
411 | add $grp aio_open $src, O_RDONLY, 0, sub { |
474 | add $grp aio_open $src, O_RDONLY, 0, sub { |
412 | if (my $src_fh = $_[0]) { |
475 | if (my $src_fh = $_[0]) { |
413 | my @stat = stat $src_fh; |
476 | my @stat = stat $src_fh; |
414 | |
477 | |
415 | aioreq_pri $pri; |
478 | aioreq_pri $pri; |
416 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
479 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
417 | if (my $dst_fh = $_[0]) { |
480 | if (my $dst_fh = $_[0]) { |
418 | aioreq_pri $pri; |
481 | aioreq_pri $pri; |
419 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
482 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
420 | if ($_[0] == $stat[7]) { |
483 | if ($_[0] == $stat[7]) { |
421 | $grp->result (0); |
484 | $grp->result (0); |
422 | close $src_fh; |
485 | close $src_fh; |
423 | |
486 | |
424 | # those should not normally block. should. should. |
487 | # those should not normally block. should. should. |
425 | utime $stat[8], $stat[9], $dst; |
488 | utime $stat[8], $stat[9], $dst; |
426 | chmod $stat[2] & 07777, $dst_fh; |
489 | chmod $stat[2] & 07777, $dst_fh; |
427 | chown $stat[4], $stat[5], $dst_fh; |
490 | chown $stat[4], $stat[5], $dst_fh; |
428 | close $dst_fh; |
491 | close $dst_fh; |
429 | } else { |
492 | } else { |
430 | $grp->result (-1); |
493 | $grp->result (-1); |
431 | close $src_fh; |
494 | close $src_fh; |
432 | close $dst_fh; |
495 | close $dst_fh; |
433 | |
496 | |
434 | aioreq $pri; |
497 | aioreq $pri; |
435 | add $grp aio_unlink $dst; |
498 | add $grp aio_unlink $dst; |
|
|
499 | } |
436 | } |
500 | }; |
|
|
501 | } else { |
|
|
502 | $grp->result (-1); |
437 | }; |
503 | } |
438 | } else { |
|
|
439 | $grp->result (-1); |
|
|
440 | } |
504 | }, |
|
|
505 | |
|
|
506 | } else { |
|
|
507 | $grp->result (-1); |
441 | }, |
508 | } |
442 | |
|
|
443 | } else { |
|
|
444 | $grp->result (-1); |
|
|
445 | } |
509 | }; |
|
|
510 | |
|
|
511 | $grp |
446 | }; |
512 | } |
447 | |
|
|
448 | $grp |
|
|
449 | } |
513 | } |
450 | |
514 | |
451 | =item aio_move $srcpath, $dstpath, $callback->($status) |
515 | =item aio_move $srcpath, $dstpath, $callback->($status) |
452 | |
516 | |
453 | Try to move the I<file> (directories not supported as either source or |
517 | Try to move the I<file> (directories not supported as either source or |
… | |
… | |
459 | that is successful, unlinking the C<$srcpath>. |
523 | that is successful, unlinking the C<$srcpath>. |
460 | |
524 | |
461 | =cut |
525 | =cut |
462 | |
526 | |
463 | sub aio_move($$;$) { |
527 | sub aio_move($$;$) { |
|
|
528 | aio_block { |
464 | my ($src, $dst, $cb) = @_; |
529 | my ($src, $dst, $cb) = @_; |
465 | |
530 | |
466 | my $pri = aioreq_pri; |
531 | my $pri = aioreq_pri; |
467 | my $grp = aio_group $cb; |
532 | my $grp = aio_group $cb; |
468 | |
533 | |
469 | aioreq_pri $pri; |
534 | aioreq_pri $pri; |
470 | add $grp aio_rename $src, $dst, sub { |
535 | add $grp aio_rename $src, $dst, sub { |
471 | if ($_[0] && $! == EXDEV) { |
536 | if ($_[0] && $! == EXDEV) { |
472 | aioreq_pri $pri; |
537 | aioreq_pri $pri; |
473 | add $grp aio_copy $src, $dst, sub { |
538 | add $grp aio_copy $src, $dst, sub { |
|
|
539 | $grp->result ($_[0]); |
|
|
540 | |
|
|
541 | if (!$_[0]) { |
|
|
542 | aioreq_pri $pri; |
|
|
543 | add $grp aio_unlink $src; |
|
|
544 | } |
|
|
545 | }; |
|
|
546 | } else { |
474 | $grp->result ($_[0]); |
547 | $grp->result ($_[0]); |
475 | |
|
|
476 | if (!$_[0]) { |
|
|
477 | aioreq_pri $pri; |
|
|
478 | add $grp aio_unlink $src; |
|
|
479 | } |
|
|
480 | }; |
548 | } |
481 | } else { |
|
|
482 | $grp->result ($_[0]); |
|
|
483 | } |
549 | }; |
|
|
550 | |
|
|
551 | $grp |
484 | }; |
552 | } |
485 | |
|
|
486 | $grp |
|
|
487 | } |
553 | } |
488 | |
554 | |
489 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
555 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
490 | |
556 | |
491 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
557 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
… | |
… | |
539 | directory counting heuristic. |
605 | directory counting heuristic. |
540 | |
606 | |
541 | =cut |
607 | =cut |
542 | |
608 | |
543 | sub aio_scandir($$$) { |
609 | sub aio_scandir($$$) { |
|
|
610 | aio_block { |
544 | my ($path, $maxreq, $cb) = @_; |
611 | my ($path, $maxreq, $cb) = @_; |
545 | |
612 | |
546 | my $pri = aioreq_pri; |
613 | my $pri = aioreq_pri; |
547 | |
614 | |
548 | my $grp = aio_group $cb; |
615 | my $grp = aio_group $cb; |
549 | |
616 | |
550 | $maxreq = 4 if $maxreq <= 0; |
617 | $maxreq = 4 if $maxreq <= 0; |
551 | |
618 | |
552 | # stat once |
619 | # stat once |
553 | aioreq_pri $pri; |
|
|
554 | add $grp aio_stat $path, sub { |
|
|
555 | return $grp->result () if $_[0]; |
|
|
556 | my $now = time; |
|
|
557 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
558 | |
|
|
559 | # read the directory entries |
|
|
560 | aioreq_pri $pri; |
620 | aioreq_pri $pri; |
561 | add $grp aio_readdir $path, sub { |
621 | add $grp aio_stat $path, sub { |
562 | my $entries = shift |
|
|
563 | or return $grp->result (); |
622 | return $grp->result () if $_[0]; |
|
|
623 | my $now = time; |
|
|
624 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
564 | |
625 | |
565 | # stat the dir another time |
626 | # read the directory entries |
566 | aioreq_pri $pri; |
627 | aioreq_pri $pri; |
|
|
628 | add $grp aio_readdir $path, sub { |
|
|
629 | my $entries = shift |
|
|
630 | or return $grp->result (); |
|
|
631 | |
|
|
632 | # stat the dir another time |
|
|
633 | aioreq_pri $pri; |
567 | add $grp aio_stat $path, sub { |
634 | add $grp aio_stat $path, sub { |
568 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
635 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
569 | |
636 | |
570 | my $ndirs; |
637 | my $ndirs; |
571 | |
638 | |
572 | # take the slow route if anything looks fishy |
639 | # take the slow route if anything looks fishy |
573 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
640 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
574 | $ndirs = -1; |
641 | $ndirs = -1; |
575 | } else { |
642 | } else { |
576 | # if nlink == 2, we are finished |
643 | # if nlink == 2, we are finished |
577 | # on non-posix-fs's, we rely on nlink < 2 |
644 | # on non-posix-fs's, we rely on nlink < 2 |
578 | $ndirs = (stat _)[3] - 2 |
645 | $ndirs = (stat _)[3] - 2 |
579 | or return $grp->result ([], $entries); |
646 | or return $grp->result ([], $entries); |
580 | } |
647 | } |
581 | |
648 | |
582 | # sort into likely dirs and likely nondirs |
649 | # sort into likely dirs and likely nondirs |
583 | # dirs == files without ".", short entries first |
650 | # dirs == files without ".", short entries first |
584 | $entries = [map $_->[0], |
651 | $entries = [map $_->[0], |
585 | sort { $b->[1] cmp $a->[1] } |
652 | sort { $b->[1] cmp $a->[1] } |
586 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
653 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
587 | @$entries]; |
654 | @$entries]; |
588 | |
655 | |
589 | my (@dirs, @nondirs); |
656 | my (@dirs, @nondirs); |
590 | |
657 | |
591 | my $statgrp = add $grp aio_group sub { |
658 | my $statgrp = add $grp aio_group sub { |
592 | $grp->result (\@dirs, \@nondirs); |
659 | $grp->result (\@dirs, \@nondirs); |
593 | }; |
660 | }; |
594 | |
661 | |
595 | limit $statgrp $maxreq; |
662 | limit $statgrp $maxreq; |
596 | feed $statgrp sub { |
663 | feed $statgrp sub { |
597 | return unless @$entries; |
664 | return unless @$entries; |
598 | my $entry = pop @$entries; |
665 | my $entry = pop @$entries; |
599 | |
666 | |
600 | aioreq_pri $pri; |
667 | aioreq_pri $pri; |
601 | add $statgrp aio_stat "$path/$entry/.", sub { |
668 | add $statgrp aio_stat "$path/$entry/.", sub { |
602 | if ($_[0] < 0) { |
669 | if ($_[0] < 0) { |
603 | push @nondirs, $entry; |
670 | push @nondirs, $entry; |
604 | } else { |
671 | } else { |
605 | # need to check for real directory |
672 | # need to check for real directory |
606 | aioreq_pri $pri; |
673 | aioreq_pri $pri; |
607 | add $statgrp aio_lstat "$path/$entry", sub { |
674 | add $statgrp aio_lstat "$path/$entry", sub { |
608 | if (-d _) { |
675 | if (-d _) { |
609 | push @dirs, $entry; |
676 | push @dirs, $entry; |
610 | |
677 | |
611 | unless (--$ndirs) { |
678 | unless (--$ndirs) { |
612 | push @nondirs, @$entries; |
679 | push @nondirs, @$entries; |
613 | feed $statgrp; |
680 | feed $statgrp; |
|
|
681 | } |
|
|
682 | } else { |
|
|
683 | push @nondirs, $entry; |
614 | } |
684 | } |
615 | } else { |
|
|
616 | push @nondirs, $entry; |
|
|
617 | } |
685 | } |
618 | } |
686 | } |
619 | } |
687 | }; |
620 | }; |
688 | }; |
621 | }; |
689 | }; |
622 | }; |
690 | }; |
623 | }; |
691 | }; |
|
|
692 | |
|
|
693 | $grp |
624 | }; |
694 | } |
625 | |
|
|
626 | $grp |
|
|
627 | } |
695 | } |
628 | |
696 | |
629 | =item aio_fsync $fh, $callback->($status) |
697 | =item aio_fsync $fh, $callback->($status) |
630 | |
698 | |
631 | Asynchronously call fsync on the given filehandle and call the callback |
699 | Asynchronously call fsync on the given filehandle and call the callback |
… | |
… | |
845 | |
913 | |
846 | =back |
914 | =back |
847 | |
915 | |
848 | =head2 SUPPORT FUNCTIONS |
916 | =head2 SUPPORT FUNCTIONS |
849 | |
917 | |
|
|
918 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
|
|
919 | |
850 | =over 4 |
920 | =over 4 |
851 | |
921 | |
852 | =item $fileno = IO::AIO::poll_fileno |
922 | =item $fileno = IO::AIO::poll_fileno |
853 | |
923 | |
854 | Return the I<request result pipe file descriptor>. This filehandle must be |
924 | Return the I<request result pipe file descriptor>. This filehandle must be |
… | |
… | |
858 | |
928 | |
859 | See C<poll_cb> for an example. |
929 | See C<poll_cb> for an example. |
860 | |
930 | |
861 | =item IO::AIO::poll_cb |
931 | =item IO::AIO::poll_cb |
862 | |
932 | |
863 | Process all outstanding events on the result pipe. You have to call this |
933 | Process some outstanding events on the result pipe. You have to call this |
864 | regularly. Returns the number of events processed. Returns immediately |
934 | regularly. Returns the number of events processed. Returns immediately |
865 | when no events are outstanding. |
935 | when no events are outstanding. The amount of events processed depends on |
|
|
936 | the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
866 | |
937 | |
867 | If not all requests were processed for whatever reason, the filehandle |
938 | If not all requests were processed for whatever reason, the filehandle |
868 | will still be ready when C<poll_cb> returns. |
939 | will still be ready when C<poll_cb> returns. |
869 | |
940 | |
870 | Example: Install an Event watcher that automatically calls |
941 | Example: Install an Event watcher that automatically calls |
… | |
… | |
872 | |
943 | |
873 | Event->io (fd => IO::AIO::poll_fileno, |
944 | Event->io (fd => IO::AIO::poll_fileno, |
874 | poll => 'r', async => 1, |
945 | poll => 'r', async => 1, |
875 | cb => \&IO::AIO::poll_cb); |
946 | cb => \&IO::AIO::poll_cb); |
876 | |
947 | |
877 | =item IO::AIO::poll_some $max_requests |
948 | =item IO::AIO::max_poll_reqs $nreqs |
878 | |
949 | |
879 | Similar to C<poll_cb>, but only processes up to C<$max_requests> requests |
950 | =item IO::AIO::max_poll_time $seconds |
880 | at a time. |
|
|
881 | |
951 | |
882 | Useful if you want to ensure some level of interactiveness when perl is |
952 | These set the maximum number of requests (default C<0>, meaning infinity) |
883 | not fast enough to process all requests in time. |
953 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
|
|
954 | the maximum amount of time (default C<0>, meaning infinity) spent in |
|
|
955 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
|
|
956 | of time C<poll_cb> is allowed to use). |
|
|
957 | |
|
|
958 | Setting C<max_poll_time> to a non-zero value creates an overhead of one |
|
|
959 | syscall per request processed, which is not normally a problem unless your |
|
|
960 | callbacks are really really fast or your OS is really really slow (I am |
|
|
961 | not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead. |
|
|
962 | |
|
|
963 | Setting these is useful if you want to ensure some level of |
|
|
964 | interactiveness when perl is not fast enough to process all requests in |
|
|
965 | time. |
|
|
966 | |
|
|
967 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
884 | |
968 | |
885 | Example: Install an Event watcher that automatically calls |
969 | Example: Install an Event watcher that automatically calls |
886 | IO::AIO::poll_some with low priority, to ensure that other parts of the |
970 | IO::AIO::poll_cb with low priority, to ensure that other parts of the |
887 | program get the CPU sometimes even under high AIO load. |
971 | program get the CPU sometimes even under high AIO load. |
888 | |
972 | |
|
|
973 | # try not to spend much more than 0.1s in poll_cb |
|
|
974 | IO::AIO::max_poll_time 0.1; |
|
|
975 | |
|
|
976 | # use a low priority so other tasks have priority |
889 | Event->io (fd => IO::AIO::poll_fileno, |
977 | Event->io (fd => IO::AIO::poll_fileno, |
890 | poll => 'r', nice => 1, |
978 | poll => 'r', nice => 1, |
891 | cb => sub { IO::AIO::poll_some 256 }); |
979 | cb => &IO::AIO::poll_cb); |
892 | |
980 | |
893 | =item IO::AIO::poll_wait |
981 | =item IO::AIO::poll_wait |
894 | |
982 | |
|
|
983 | If there are any outstanding requests and none of them in the result |
895 | Wait till the result filehandle becomes ready for reading (simply does a |
984 | phase, wait till the result filehandle becomes ready for reading (simply |
896 | C<select> on the filehandle. This is useful if you want to synchronously wait |
985 | does a C<select> on the filehandle. This is useful if you want to |
897 | for some requests to finish). |
986 | synchronously wait for some requests to finish). |
898 | |
987 | |
899 | See C<nreqs> for an example. |
988 | See C<nreqs> for an example. |
900 | |
989 | |
|
|
990 | =item IO::AIO::poll |
|
|
991 | |
|
|
992 | Waits until some requests have been handled. |
|
|
993 | |
|
|
994 | Returns the number of requests processed, but is otherwise strictly |
|
|
995 | equivalent to: |
|
|
996 | |
|
|
997 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
998 | |
901 | =item IO::AIO::nreqs |
999 | =item IO::AIO::flush |
902 | |
1000 | |
903 | Returns the number of requests currently in the ready, execute or pending |
1001 | Wait till all outstanding AIO requests have been handled. |
904 | states (i.e. for which their callback has not been invoked yet). |
|
|
905 | |
1002 | |
906 | Example: wait till there are no outstanding requests anymore: |
1003 | Strictly equivalent to: |
907 | |
1004 | |
908 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1005 | IO::AIO::poll_wait, IO::AIO::poll_cb |
909 | while IO::AIO::nreqs; |
1006 | while IO::AIO::nreqs; |
910 | |
1007 | |
911 | =item IO::AIO::nready |
1008 | =head3 CONTROLLING THE NUMBER OF THREADS |
912 | |
|
|
913 | Returns the number of requests currently in the ready state (not yet |
|
|
914 | executed). |
|
|
915 | |
|
|
916 | =item IO::AIO::npending |
|
|
917 | |
|
|
918 | Returns the number of requests currently in the pending state (executed, |
|
|
919 | but not yet processed by poll_cb). |
|
|
920 | |
|
|
921 | =item IO::AIO::flush |
|
|
922 | |
|
|
923 | Wait till all outstanding AIO requests have been handled. |
|
|
924 | |
|
|
925 | Strictly equivalent to: |
|
|
926 | |
|
|
927 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
928 | while IO::AIO::nreqs; |
|
|
929 | |
|
|
930 | =item IO::AIO::poll |
|
|
931 | |
|
|
932 | Waits until some requests have been handled. |
|
|
933 | |
|
|
934 | Strictly equivalent to: |
|
|
935 | |
|
|
936 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
937 | if IO::AIO::nreqs; |
|
|
938 | |
1009 | |
939 | =item IO::AIO::min_parallel $nthreads |
1010 | =item IO::AIO::min_parallel $nthreads |
940 | |
1011 | |
941 | Set the minimum number of AIO threads to C<$nthreads>. The current |
1012 | Set the minimum number of AIO threads to C<$nthreads>. The current |
942 | default is C<8>, which means eight asynchronous operations can execute |
1013 | default is C<8>, which means eight asynchronous operations can execute |
943 | concurrently at any one time (the number of outstanding requests, |
1014 | concurrently at any one time (the number of outstanding requests, |
944 | however, is unlimited). |
1015 | however, is unlimited). |
945 | |
1016 | |
946 | IO::AIO starts threads only on demand, when an AIO request is queued and |
1017 | IO::AIO starts threads only on demand, when an AIO request is queued and |
947 | no free thread exists. |
1018 | no free thread exists. Please note that queueing up a hundred requests can |
|
|
1019 | create demand for a hundred threads, even if it turns out that everything |
|
|
1020 | is in the cache and could have been processed faster by a single thread. |
948 | |
1021 | |
949 | It is recommended to keep the number of threads relatively low, as some |
1022 | It is recommended to keep the number of threads relatively low, as some |
950 | Linux kernel versions will scale negatively with the number of threads |
1023 | Linux kernel versions will scale negatively with the number of threads |
951 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
1024 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
952 | versions, 4-32 threads should be fine. |
1025 | versions, 4-32 threads should be fine. |
… | |
… | |
966 | This module automatically runs C<max_parallel 0> at program end, to ensure |
1039 | This module automatically runs C<max_parallel 0> at program end, to ensure |
967 | that all threads are killed and that there are no outstanding requests. |
1040 | that all threads are killed and that there are no outstanding requests. |
968 | |
1041 | |
969 | Under normal circumstances you don't need to call this function. |
1042 | Under normal circumstances you don't need to call this function. |
970 | |
1043 | |
|
|
1044 | =item IO::AIO::max_idle $nthreads |
|
|
1045 | |
|
|
1046 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
|
|
1047 | threads that did not get a request to process within 10 seconds). That |
|
|
1048 | means if a thread becomes idle while C<$nthreads> other threads are also |
|
|
1049 | idle, it will free its resources and exit. |
|
|
1050 | |
|
|
1051 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
|
|
1052 | to allow for extremely high load situations, but want to free resources |
|
|
1053 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
|
|
1054 | |
|
|
1055 | The default is probably ok in most situations, especially if thread |
|
|
1056 | creation is fast. If thread creation is very slow on your system you might |
|
|
1057 | want to use larger values. |
|
|
1058 | |
971 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
1059 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
972 | |
1060 | |
973 | This is a very bad function to use in interactive programs because it |
1061 | This is a very bad function to use in interactive programs because it |
974 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1062 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
975 | use an C<aio_group> together with a feed callback. |
1063 | use an C<aio_group> together with a feed callback. |
… | |
… | |
984 | |
1072 | |
985 | You can still queue as many requests as you want. Therefore, |
1073 | You can still queue as many requests as you want. Therefore, |
986 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
1074 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
987 | as a stop gap to shield against fatal memory overflow (with large values). |
1075 | as a stop gap to shield against fatal memory overflow (with large values). |
988 | |
1076 | |
|
|
1077 | =head3 STATISTICAL INFORMATION |
|
|
1078 | |
|
|
1079 | =item IO::AIO::nreqs |
|
|
1080 | |
|
|
1081 | Returns the number of requests currently in the ready, execute or pending |
|
|
1082 | states (i.e. for which their callback has not been invoked yet). |
|
|
1083 | |
|
|
1084 | Example: wait till there are no outstanding requests anymore: |
|
|
1085 | |
|
|
1086 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1087 | while IO::AIO::nreqs; |
|
|
1088 | |
|
|
1089 | =item IO::AIO::nready |
|
|
1090 | |
|
|
1091 | Returns the number of requests currently in the ready state (not yet |
|
|
1092 | executed). |
|
|
1093 | |
|
|
1094 | =item IO::AIO::npending |
|
|
1095 | |
|
|
1096 | Returns the number of requests currently in the pending state (executed, |
|
|
1097 | but not yet processed by poll_cb). |
|
|
1098 | |
989 | =back |
1099 | =back |
990 | |
1100 | |
991 | =cut |
1101 | =cut |
992 | |
1102 | |
993 | # support function to convert a fd into a perl filehandle |
1103 | # support function to convert a fd into a perl filehandle |
… | |
… | |
1006 | *$sym |
1116 | *$sym |
1007 | } |
1117 | } |
1008 | |
1118 | |
1009 | min_parallel 8; |
1119 | min_parallel 8; |
1010 | |
1120 | |
1011 | END { |
1121 | END { flush } |
1012 | min_parallel 1; |
|
|
1013 | flush; |
|
|
1014 | }; |
|
|
1015 | |
1122 | |
1016 | 1; |
1123 | 1; |
1017 | |
1124 | |
1018 | =head2 FORK BEHAVIOUR |
1125 | =head2 FORK BEHAVIOUR |
1019 | |
1126 | |