… | |
… | |
4 | |
4 | |
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", IO::AIO::O_RDONLY, 0, sub { |
10 | my $fh = shift |
10 | my $fh = shift |
11 | or die "/etc/passwd: $!"; |
11 | or die "/etc/passwd: $!"; |
12 | ... |
12 | ... |
13 | }; |
13 | }; |
14 | |
14 | |
… | |
… | |
76 | |
76 | |
77 | # register the IO::AIO callback with EV |
77 | # register the IO::AIO callback with EV |
78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
79 | |
79 | |
80 | # queue the request to open /etc/passwd |
80 | # queue the request to open /etc/passwd |
81 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
81 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
82 | my $fh = shift |
82 | my $fh = shift |
83 | or die "error while opening: $!"; |
83 | or die "error while opening: $!"; |
84 | |
84 | |
85 | # stat'ing filehandles is generally non-blocking |
85 | # stat'ing filehandles is generally non-blocking |
86 | my $size = -s $fh; |
86 | my $size = -s $fh; |
… | |
… | |
168 | use common::sense; |
168 | use common::sense; |
169 | |
169 | |
170 | use base 'Exporter'; |
170 | use base 'Exporter'; |
171 | |
171 | |
172 | BEGIN { |
172 | BEGIN { |
173 | our $VERSION = '3.6'; |
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 |
179 | aio_rename aio_link aio_move aio_copy aio_group |
179 | aio_rename aio_link aio_move aio_copy aio_group |
180 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
180 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
181 | aio_chmod aio_utime aio_truncate |
181 | aio_chmod aio_utime aio_truncate |
182 | aio_msync aio_mtouch aio_statvfs); |
182 | aio_msync aio_mtouch aio_mlock aio_mlockall |
|
|
183 | aio_statvfs); |
183 | |
184 | |
184 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
185 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
185 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
186 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
186 | min_parallel max_parallel max_idle |
187 | min_parallel max_parallel max_idle idle_timeout |
187 | nreqs nready npending nthreads |
188 | nreqs nready npending nthreads |
188 | max_poll_time max_poll_reqs |
189 | max_poll_time max_poll_reqs |
189 | sendfile fadvise); |
190 | sendfile fadvise madvise |
|
|
191 | mmap munmap munlock munlockall); |
190 | |
192 | |
191 | push @AIO_REQ, qw(aio_busy); # not exported |
193 | push @AIO_REQ, qw(aio_busy); # not exported |
192 | |
194 | |
193 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
195 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
194 | |
196 | |
… | |
… | |
239 | aio_fdatasync $fh, $callback->($status) |
241 | aio_fdatasync $fh, $callback->($status) |
240 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
242 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
241 | aio_pathsync $path, $callback->($status) |
243 | aio_pathsync $path, $callback->($status) |
242 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
244 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
243 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
245 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
|
|
246 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
|
|
247 | aio_mlockall $flags, $callback->($status) |
244 | aio_group $callback->(...) |
248 | aio_group $callback->(...) |
245 | aio_nop $callback->() |
249 | aio_nop $callback->() |
246 | |
250 | |
247 | $prev_pri = aioreq_pri [$pri] |
251 | $prev_pri = aioreq_pri [$pri] |
248 | aioreq_nice $pri_adjust |
252 | aioreq_nice $pri_adjust |
… | |
… | |
254 | IO::AIO::max_poll_reqs $nreqs |
258 | IO::AIO::max_poll_reqs $nreqs |
255 | IO::AIO::max_poll_time $seconds |
259 | IO::AIO::max_poll_time $seconds |
256 | IO::AIO::min_parallel $nthreads |
260 | IO::AIO::min_parallel $nthreads |
257 | IO::AIO::max_parallel $nthreads |
261 | IO::AIO::max_parallel $nthreads |
258 | IO::AIO::max_idle $nthreads |
262 | IO::AIO::max_idle $nthreads |
|
|
263 | IO::AIO::idle_timeout $seconds |
259 | IO::AIO::max_outstanding $maxreqs |
264 | IO::AIO::max_outstanding $maxreqs |
260 | IO::AIO::nreqs |
265 | IO::AIO::nreqs |
261 | IO::AIO::nready |
266 | IO::AIO::nready |
262 | IO::AIO::npending |
267 | IO::AIO::npending |
263 | |
268 | |
264 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
269 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
265 | IO::AIO::fadvise $fh, $offset, $len, $advice |
270 | IO::AIO::fadvise $fh, $offset, $len, $advice |
266 | IO::AIO::mlockall $flags |
271 | IO::AIO::madvise $scalar, $offset, $length, $advice |
|
|
272 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
|
|
273 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
267 | IO::AIO::munlockall |
274 | IO::AIO::munlockall |
268 | |
275 | |
269 | =head2 AIO REQUEST FUNCTIONS |
276 | =head2 AIO REQUEST FUNCTIONS |
270 | |
277 | |
271 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
278 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
… | |
… | |
352 | by the umask in effect then the request is being executed, so better never |
359 | by the umask in effect then the request is being executed, so better never |
353 | change the umask. |
360 | change the umask. |
354 | |
361 | |
355 | Example: |
362 | Example: |
356 | |
363 | |
357 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
364 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
358 | if ($_[0]) { |
365 | if ($_[0]) { |
359 | print "open successful, fh is $_[0]\n"; |
366 | print "open successful, fh is $_[0]\n"; |
360 | ... |
367 | ... |
361 | } else { |
368 | } else { |
362 | die "open failed: $!\n"; |
369 | die "open failed: $!\n"; |
363 | } |
370 | } |
364 | }; |
371 | }; |
365 | |
372 | |
|
|
373 | In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>, |
|
|
374 | C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the |
|
|
375 | following POSIX and non-POSIX constants are available (missing ones on |
|
|
376 | your system are, as usual, C<0>): |
|
|
377 | |
|
|
378 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
|
|
379 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
|
|
380 | C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>. |
|
|
381 | |
366 | |
382 | |
367 | =item aio_close $fh, $callback->($status) |
383 | =item aio_close $fh, $callback->($status) |
368 | |
384 | |
369 | Asynchronously close a file and call the callback with the result |
385 | Asynchronously close a file and call the callback with the result |
370 | code. |
386 | code. |
… | |
… | |
420 | |
436 | |
421 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
437 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
422 | reading at byte offset C<$in_offset>, and starts writing at the current |
438 | reading at byte offset C<$in_offset>, and starts writing at the current |
423 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
439 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
424 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
440 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
425 | other. |
441 | other. The same C<$in_fh> works fine though, as this function does not |
|
|
442 | move or use the file offset of C<$in_fh>. |
426 | |
443 | |
|
|
444 | Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than |
|
|
445 | are written, and there is no way to find out how many more bytes have been |
|
|
446 | read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the |
|
|
447 | number of bytes written to C<$out_fh>. Only if the result value equals |
|
|
448 | C<$length> one can assume that C<$length> bytes have been read. |
|
|
449 | |
|
|
450 | Unlike with other C<aio_> functions, it makes a lot of sense to use |
|
|
451 | C<aio_sendfile> on non-blocking sockets, as long as one end (typically |
|
|
452 | the C<$in_fh>) is a file - the file I/O will then be asynchronous, while |
|
|
453 | the socket I/O will be non-blocking. Note, however, that you can run |
|
|
454 | into a trap where C<aio_sendfile> reads some data with readahead, then |
|
|
455 | fails to write all data, and when the socket is ready the next time, the |
|
|
456 | data in the cache is already lost, forcing C<aio_sendfile> to again hit |
|
|
457 | the disk. Explicit C<aio_read> + C<aio_write> let's you better control |
|
|
458 | resource usage. |
|
|
459 | |
427 | This call tries to make use of a native C<sendfile> syscall to provide |
460 | This call tries to make use of a native C<sendfile>-like syscall to |
428 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
461 | provide zero-copy operation. For this to work, C<$out_fh> should refer to |
429 | socket, and C<$in_fh> should refer to an mmap'able file. |
462 | a socket, and C<$in_fh> should refer to an mmap'able file. |
430 | |
463 | |
431 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
464 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
432 | C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>, |
465 | C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or |
433 | it will be emulated, so you can call C<aio_sendfile> on any type of |
466 | C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any |
434 | filehandle regardless of the limitations of the operating system. |
467 | type of filehandle regardless of the limitations of the operating system. |
435 | |
468 | |
436 | Please note, however, that C<aio_sendfile> can read more bytes from |
469 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
437 | C<$in_fh> than are written, and there is no way to find out how many |
470 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
438 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
471 | on many systems, this implementation tries to work around some known bugs |
439 | provides the number of bytes written to C<$out_fh>. Only if the result |
472 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
440 | value equals C<$length> one can assume that C<$length> bytes have been |
473 | so you really really should check the return value of C<aio_sendfile> - |
441 | read. |
474 | fewre bytes than expected might have been transferred. |
442 | |
475 | |
443 | |
476 | |
444 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
477 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
445 | |
478 | |
446 | C<aio_readahead> populates the page cache with data from a file so that |
479 | C<aio_readahead> populates the page cache with data from a file so that |
… | |
… | |
468 | for an explanation. |
501 | for an explanation. |
469 | |
502 | |
470 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
503 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
471 | error when stat'ing a large file, the results will be silently truncated |
504 | error when stat'ing a large file, the results will be silently truncated |
472 | unless perl itself is compiled with large file support. |
505 | unless perl itself is compiled with large file support. |
|
|
506 | |
|
|
507 | To help interpret the mode and dev/rdev stat values, IO::AIO offers the |
|
|
508 | following constants and functions (if not implemented, the constants will |
|
|
509 | be C<0> and the functions will either C<croak> or fall back on traditional |
|
|
510 | behaviour). |
|
|
511 | |
|
|
512 | C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, |
|
|
513 | C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, |
|
|
514 | C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. |
473 | |
515 | |
474 | Example: Print the length of F</etc/passwd>: |
516 | Example: Print the length of F</etc/passwd>: |
475 | |
517 | |
476 | aio_stat "/etc/passwd", sub { |
518 | aio_stat "/etc/passwd", sub { |
477 | $_[0] and die "stat failed: $!"; |
519 | $_[0] and die "stat failed: $!"; |
… | |
… | |
579 | |
621 | |
580 | The only (POSIX-) portable way of calling this function is: |
622 | The only (POSIX-) portable way of calling this function is: |
581 | |
623 | |
582 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
624 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
583 | |
625 | |
|
|
626 | See C<aio_stat> for info about some potentially helpful extra constants |
|
|
627 | and functions. |
584 | |
628 | |
585 | =item aio_link $srcpath, $dstpath, $callback->($status) |
629 | =item aio_link $srcpath, $dstpath, $callback->($status) |
586 | |
630 | |
587 | Asynchronously create a new link to the existing object at C<$srcpath> at |
631 | Asynchronously create a new link to the existing object at C<$srcpath> at |
588 | the path C<$dstpath> and call the callback with the result code. |
632 | the path C<$dstpath> and call the callback with the result code. |
… | |
… | |
641 | |
685 | |
642 | =over 4 |
686 | =over 4 |
643 | |
687 | |
644 | =item IO::AIO::READDIR_DENTS |
688 | =item IO::AIO::READDIR_DENTS |
645 | |
689 | |
646 | When this flag is off, then the callback gets an arrayref with of names |
690 | When this flag is off, then the callback gets an arrayref consisting of |
647 | only (as with C<aio_readdir>), otherwise it gets an arrayref with |
691 | names only (as with C<aio_readdir>), otherwise it gets an arrayref with |
648 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
692 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
649 | entry in more detail. |
693 | entry in more detail. |
650 | |
694 | |
651 | C<$name> is the name of the entry. |
695 | C<$name> is the name of the entry. |
652 | |
696 | |
… | |
… | |
665 | systems that do not deliver the inode information. |
709 | systems that do not deliver the inode information. |
666 | |
710 | |
667 | =item IO::AIO::READDIR_DIRS_FIRST |
711 | =item IO::AIO::READDIR_DIRS_FIRST |
668 | |
712 | |
669 | When this flag is set, then the names will be returned in an order where |
713 | When this flag is set, then the names will be returned in an order where |
670 | likely directories come first. This is useful when you need to quickly |
714 | likely directories come first, in optimal stat order. This is useful when |
671 | find directories, or you want to find all directories while avoiding to |
715 | you need to quickly find directories, or you want to find all directories |
672 | stat() each entry. |
716 | while avoiding to stat() each entry. |
673 | |
717 | |
674 | If the system returns type information in readdir, then this is used |
718 | If the system returns type information in readdir, then this is used |
675 | to find directories directly. Otherwise, likely directories are files |
719 | to find directories directly. Otherwise, likely directories are names |
676 | beginning with ".", or otherwise files with no dots, of which files with |
720 | beginning with ".", or otherwise names with no dots, of which names with |
677 | short names are tried first. |
721 | short names are tried first. |
678 | |
722 | |
679 | =item IO::AIO::READDIR_STAT_ORDER |
723 | =item IO::AIO::READDIR_STAT_ORDER |
680 | |
724 | |
681 | When this flag is set, then the names will be returned in an order |
725 | When this flag is set, then the names will be returned in an order |
… | |
… | |
826 | if ($_[0] && $! == EXDEV) { |
870 | if ($_[0] && $! == EXDEV) { |
827 | aioreq_pri $pri; |
871 | aioreq_pri $pri; |
828 | add $grp aio_copy $src, $dst, sub { |
872 | add $grp aio_copy $src, $dst, sub { |
829 | $grp->result ($_[0]); |
873 | $grp->result ($_[0]); |
830 | |
874 | |
831 | if (!$_[0]) { |
875 | unless ($_[0]) { |
832 | aioreq_pri $pri; |
876 | aioreq_pri $pri; |
833 | add $grp aio_unlink $src; |
877 | add $grp aio_unlink $src; |
834 | } |
878 | } |
835 | }; |
879 | }; |
836 | } else { |
880 | } else { |
… | |
… | |
1108 | as for C<aio_msync>, above, except for flags, which must be either |
1152 | as for C<aio_msync>, above, except for flags, which must be either |
1109 | C<0> (which reads all pages and ensures they are instantiated) or |
1153 | C<0> (which reads all pages and ensures they are instantiated) or |
1110 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1154 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1111 | writing an octet from it, which dirties the page). |
1155 | writing an octet from it, which dirties the page). |
1112 | |
1156 | |
|
|
1157 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
|
|
1158 | |
|
|
1159 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
|
|
1160 | scalars. |
|
|
1161 | |
|
|
1162 | It reads in all the pages of the underlying storage into memory (if any) |
|
|
1163 | and locks them, so they are not getting swapped/paged out or removed. |
|
|
1164 | |
|
|
1165 | If C<$length> is undefined, then the scalar will be locked till the end. |
|
|
1166 | |
|
|
1167 | On systems that do not implement C<mlock>, this function returns C<-1> |
|
|
1168 | and sets errno to C<ENOSYS>. |
|
|
1169 | |
|
|
1170 | Note that the corresponding C<munlock> is synchronous and is |
|
|
1171 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1172 | |
|
|
1173 | Example: open a file, mmap and mlock it - both will be undone when |
|
|
1174 | C<$data> gets destroyed. |
|
|
1175 | |
|
|
1176 | open my $fh, "<", $path or die "$path: $!"; |
|
|
1177 | my $data; |
|
|
1178 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
|
|
1179 | aio_mlock $data; # mlock in background |
|
|
1180 | |
|
|
1181 | =item aio_mlockall $flags, $callback->($status) |
|
|
1182 | |
|
|
1183 | Calls the C<mlockall> function with the given C<$flags> (a combination of |
|
|
1184 | C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>). |
|
|
1185 | |
|
|
1186 | On systems that do not implement C<mlockall>, this function returns C<-1> |
|
|
1187 | and sets errno to C<ENOSYS>. |
|
|
1188 | |
|
|
1189 | Note that the corresponding C<munlockall> is synchronous and is |
|
|
1190 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1191 | |
|
|
1192 | Example: asynchronously lock all current and future pages into memory. |
|
|
1193 | |
|
|
1194 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
1195 | |
1113 | =item aio_group $callback->(...) |
1196 | =item aio_group $callback->(...) |
1114 | |
1197 | |
1115 | This is a very special aio request: Instead of doing something, it is a |
1198 | This is a very special aio request: Instead of doing something, it is a |
1116 | container for other aio requests, which is useful if you want to bundle |
1199 | container for other aio requests, which is useful if you want to bundle |
1117 | many requests into a single, composite, request with a definite callback |
1200 | many requests into a single, composite, request with a definite callback |
… | |
… | |
1340 | |
1423 | |
1341 | See C<poll_cb> for an example. |
1424 | See C<poll_cb> for an example. |
1342 | |
1425 | |
1343 | =item IO::AIO::poll_cb |
1426 | =item IO::AIO::poll_cb |
1344 | |
1427 | |
1345 | Process some outstanding events on the result pipe. You have to call this |
1428 | Process some outstanding events on the result pipe. You have to call |
1346 | regularly. Returns C<0> if all events could be processed, or C<-1> if it |
1429 | this regularly. Returns C<0> if all events could be processed (or there |
1347 | returned earlier for whatever reason. Returns immediately when no events |
1430 | were no events to process), or C<-1> if it returned earlier for whatever |
1348 | are outstanding. The amount of events processed depends on the settings of |
1431 | reason. Returns immediately when no events are outstanding. The amount of |
1349 | C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
1432 | events processed depends on the settings of C<IO::AIO::max_poll_req> and |
|
|
1433 | C<IO::AIO::max_poll_time>. |
1350 | |
1434 | |
1351 | If not all requests were processed for whatever reason, the filehandle |
1435 | If not all requests were processed for whatever reason, the filehandle |
1352 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1436 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1353 | do anything special to have it called later. |
1437 | do anything special to have it called later. |
|
|
1438 | |
|
|
1439 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
|
|
1440 | ready, it can be beneficial to call this function from loops which submit |
|
|
1441 | a lot of requests, to make sure the results get processed when they become |
|
|
1442 | available and not just when the loop is finished and the event loop takes |
|
|
1443 | over again. This function returns very fast when there are no outstanding |
|
|
1444 | requests. |
1354 | |
1445 | |
1355 | Example: Install an Event watcher that automatically calls |
1446 | Example: Install an Event watcher that automatically calls |
1356 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1447 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1357 | SYNOPSIS section, at the top of this document): |
1448 | SYNOPSIS section, at the top of this document): |
1358 | |
1449 | |
… | |
… | |
1460 | |
1551 | |
1461 | Under normal circumstances you don't need to call this function. |
1552 | Under normal circumstances you don't need to call this function. |
1462 | |
1553 | |
1463 | =item IO::AIO::max_idle $nthreads |
1554 | =item IO::AIO::max_idle $nthreads |
1464 | |
1555 | |
1465 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
1556 | Limit the number of threads (default: 4) that are allowed to idle |
1466 | threads that did not get a request to process within 10 seconds). That |
1557 | (i.e., threads that did not get a request to process within the idle |
1467 | means if a thread becomes idle while C<$nthreads> other threads are also |
1558 | timeout (default: 10 seconds). That means if a thread becomes idle while |
1468 | idle, it will free its resources and exit. |
1559 | C<$nthreads> other threads are also idle, it will free its resources and |
|
|
1560 | exit. |
1469 | |
1561 | |
1470 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
1562 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
1471 | to allow for extremely high load situations, but want to free resources |
1563 | to allow for extremely high load situations, but want to free resources |
1472 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
1564 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
1473 | |
1565 | |
1474 | The default is probably ok in most situations, especially if thread |
1566 | The default is probably ok in most situations, especially if thread |
1475 | creation is fast. If thread creation is very slow on your system you might |
1567 | creation is fast. If thread creation is very slow on your system you might |
1476 | want to use larger values. |
1568 | want to use larger values. |
1477 | |
1569 | |
|
|
1570 | =item IO::AIO::idle_timeout $seconds |
|
|
1571 | |
|
|
1572 | Sets the minimum idle timeout (default 10) after which worker threads are |
|
|
1573 | allowed to exit. SEe C<IO::AIO::max_idle>. |
|
|
1574 | |
1478 | =item IO::AIO::max_outstanding $maxreqs |
1575 | =item IO::AIO::max_outstanding $maxreqs |
|
|
1576 | |
|
|
1577 | Sets the maximum number of outstanding requests to C<$nreqs>. If |
|
|
1578 | you do queue up more than this number of requests, the next call to |
|
|
1579 | C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as |
|
|
1580 | C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no |
|
|
1581 | longer exceeded. |
|
|
1582 | |
|
|
1583 | In other words, this setting does not enforce a queue limit, but can be |
|
|
1584 | used to make poll functions block if the limit is exceeded. |
1479 | |
1585 | |
1480 | This is a very bad function to use in interactive programs because it |
1586 | This is a very bad function to use in interactive programs because it |
1481 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1587 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1482 | use an C<aio_group> together with a feed callback. |
1588 | use an C<aio_group> together with a feed callback. |
1483 | |
1589 | |
1484 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
1590 | It's main use is in scripts without an event loop - when you want to stat |
1485 | do queue up more than this number of requests, the next call to the |
1591 | a lot of files, you can write somehting like this: |
1486 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
|
|
1487 | function will block until the limit is no longer exceeded. |
|
|
1488 | |
1592 | |
1489 | The default value is very large, so there is no practical limit on the |
1593 | IO::AIO::max_outstanding 32; |
1490 | number of outstanding requests. |
|
|
1491 | |
1594 | |
1492 | You can still queue as many requests as you want. Therefore, |
1595 | for my $path (...) { |
1493 | C<max_outstanding> is mainly useful in simple scripts (with low values) or |
1596 | aio_stat $path , ...; |
1494 | as a stop gap to shield against fatal memory overflow (with large values). |
1597 | IO::AIO::poll_cb; |
|
|
1598 | } |
|
|
1599 | |
|
|
1600 | IO::AIO::flush; |
|
|
1601 | |
|
|
1602 | The call to C<poll_cb> inside the loop will normally return instantly, but |
|
|
1603 | as soon as more thna C<32> reqeusts are in-flight, it will block until |
|
|
1604 | some requests have been handled. This keeps the loop from pushing a large |
|
|
1605 | number of C<aio_stat> requests onto the queue. |
|
|
1606 | |
|
|
1607 | The default value for C<max_outstanding> is very large, so there is no |
|
|
1608 | practical limit on the number of outstanding requests. |
1495 | |
1609 | |
1496 | =back |
1610 | =back |
1497 | |
1611 | |
1498 | =head3 STATISTICAL INFORMATION |
1612 | =head3 STATISTICAL INFORMATION |
1499 | |
1613 | |
… | |
… | |
1537 | |
1651 | |
1538 | Returns the number of bytes copied, or C<-1> on error. |
1652 | Returns the number of bytes copied, or C<-1> on error. |
1539 | |
1653 | |
1540 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
1654 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
1541 | |
1655 | |
1542 | Simply calls the C<posix_fadvise> function (see it's |
1656 | Simply calls the C<posix_fadvise> function (see its |
1543 | manpage for details). The following advice constants are |
1657 | manpage for details). The following advice constants are |
1544 | avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
1658 | avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
1545 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
1659 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
1546 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
1660 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
1547 | |
1661 | |
1548 | On systems that do not implement C<posix_fadvise>, this function returns |
1662 | On systems that do not implement C<posix_fadvise>, this function returns |
1549 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
1663 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
|
|
1664 | |
|
|
1665 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
|
|
1666 | |
|
|
1667 | Simply calls the C<posix_madvise> function (see its |
|
|
1668 | manpage for details). The following advice constants are |
|
|
1669 | avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
|
|
1670 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
|
|
1671 | |
|
|
1672 | On systems that do not implement C<posix_madvise>, this function returns |
|
|
1673 | ENOSYS, otherwise the return value of C<posix_madvise>. |
|
|
1674 | |
|
|
1675 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
|
|
1676 | |
|
|
1677 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
|
|
1678 | $scalar (see its manpage for details). The following protect |
|
|
1679 | constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
|
|
1680 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
|
|
1681 | |
|
|
1682 | On systems that do not implement C<mprotect>, this function returns |
|
|
1683 | ENOSYS, otherwise the return value of C<mprotect>. |
1550 | |
1684 | |
1551 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1685 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1552 | |
1686 | |
1553 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1687 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1554 | given C<$scalar>, which will act like a string scalar. |
1688 | given C<$scalar>, which will act like a string scalar. |
… | |
… | |
1600 | |
1734 | |
1601 | =item IO::AIO::munmap $scalar |
1735 | =item IO::AIO::munmap $scalar |
1602 | |
1736 | |
1603 | Removes a previous mmap and undefines the C<$scalar>. |
1737 | Removes a previous mmap and undefines the C<$scalar>. |
1604 | |
1738 | |
1605 | =item IO::AIO::mlockall $flags |
1739 | =item IO::AIO::munlock $scalar, $offset = 0, $length = undef |
1606 | |
1740 | |
1607 | Calls the C<mlockall> function with the given C<$flags> (a combination of |
1741 | Calls the C<munlock> function, undoing the effects of a previous |
1608 | C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL__FUTURE>). |
1742 | C<aio_mlock> call (see its description for details). |
1609 | |
|
|
1610 | On systems that do not implement C<mlockall>, this function returns |
|
|
1611 | ENOSYS, otherwise the return value of C<mlockall>. |
|
|
1612 | |
1743 | |
1613 | =item IO::AIO::munlockall |
1744 | =item IO::AIO::munlockall |
1614 | |
1745 | |
1615 | Calls the C<munlockall> function. |
1746 | Calls the C<munlockall> function. |
1616 | |
1747 | |