ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/IO-AIO/AIO.pm
(Generate patch)

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.163 by root, Wed Aug 5 11:53:16 2009 UTC vs.
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC

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
25 my $req = aio_unlink "/tmp/file", sub { }; 25 my $req = aio_unlink "/tmp/file", sub { };
26 $req->cancel; # cancel request if still in queue 26 $req->cancel; # cancel request if still in queue
27 27
28 my $grp = aio_group sub { print "all stats done\n" }; 28 my $grp = aio_group sub { print "all stats done\n" };
29 add $grp aio_stat "..." for ...; 29 add $grp aio_stat "..." for ...;
30
31 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
32 use AnyEvent::AIO;
33
34 # EV integration
35 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
36
37 # Event integration
38 Event->io (fd => IO::AIO::poll_fileno,
39 poll => 'r',
40 cb => \&IO::AIO::poll_cb);
41
42 # Glib/Gtk2 integration
43 add_watch Glib::IO IO::AIO::poll_fileno,
44 in => sub { IO::AIO::poll_cb; 1 };
45
46 # Tk integration
47 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
48 readable => \&IO::AIO::poll_cb);
49
50 # Danga::Socket integration
51 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
52 \&IO::AIO::poll_cb);
53 30
54=head1 DESCRIPTION 31=head1 DESCRIPTION
55 32
56This module implements asynchronous I/O using whatever means your 33This module implements asynchronous I/O using whatever means your
57operating system supports. It is implemented as an interface to C<libeio> 34operating system supports. It is implemented as an interface to C<libeio>
99 76
100 # register the IO::AIO callback with EV 77 # register the IO::AIO callback with EV
101 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;
102 79
103 # queue the request to open /etc/passwd 80 # queue the request to open /etc/passwd
104 aio_open "/etc/passwd", O_RDONLY, 0, sub { 81 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
105 my $fh = shift 82 my $fh = shift
106 or die "error while opening: $!"; 83 or die "error while opening: $!";
107 84
108 # stat'ing filehandles is generally non-blocking 85 # stat'ing filehandles is generally non-blocking
109 my $size = -s $fh; 86 my $size = -s $fh;
191use common::sense; 168use common::sense;
192 169
193use base 'Exporter'; 170use base 'Exporter';
194 171
195BEGIN { 172BEGIN {
196 our $VERSION = '3.3'; 173 our $VERSION = '3.93';
197 174
198 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
199 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
200 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync 177 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync aio_fsync
201 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead 178 aio_fdatasync aio_sync_file_range aio_fallocate
179 aio_pathsync aio_readahead
202 aio_rename aio_link aio_move aio_copy aio_group 180 aio_rename aio_link aio_move aio_copy aio_group
203 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 181 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
204 aio_chmod aio_utime aio_truncate); 182 aio_chmod aio_utime aio_truncate
183 aio_msync aio_mtouch aio_mlock aio_mlockall
184 aio_statvfs);
205 185
206 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 186 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
207 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 187 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
208 min_parallel max_parallel max_idle 188 min_parallel max_parallel max_idle idle_timeout
209 nreqs nready npending nthreads 189 nreqs nready npending nthreads
210 max_poll_time max_poll_reqs 190 max_poll_time max_poll_reqs
211 sendfile fadvise); 191 sendfile fadvise madvise
192 mmap munmap munlock munlockall);
212 193
213 push @AIO_REQ, qw(aio_busy); # not exported 194 push @AIO_REQ, qw(aio_busy); # not exported
214 195
215 @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; 196 @IO::AIO::GRP::ISA = 'IO::AIO::REQ';
216 197
217 require XSLoader; 198 require XSLoader;
218 XSLoader::load ("IO::AIO", $VERSION); 199 XSLoader::load ("IO::AIO", $VERSION);
219} 200}
220 201
221=head1 FUNCTIONS 202=head1 FUNCTIONS
203
204=head2 QUICK OVERVIEW
205
206This section simply lists the prototypes of the most important functions
207for quick reference. See the following sections for function-by-function
208documentation.
209
210 aio_open $pathname, $flags, $mode, $callback->($fh)
211 aio_close $fh, $callback->($status)
212 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
214 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
215 aio_readahead $fh,$offset,$length, $callback->($retval)
216 aio_stat $fh_or_path, $callback->($status)
217 aio_lstat $fh, $callback->($status)
218 aio_statvfs $fh_or_path, $callback->($statvfs)
219 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
220 aio_chown $fh_or_path, $uid, $gid, $callback->($status)
221 aio_truncate $fh_or_path, $offset, $callback->($status)
222 aio_chmod $fh_or_path, $mode, $callback->($status)
223 aio_unlink $pathname, $callback->($status)
224 aio_mknod $path, $mode, $dev, $callback->($status)
225 aio_link $srcpath, $dstpath, $callback->($status)
226 aio_symlink $srcpath, $dstpath, $callback->($status)
227 aio_readlink $path, $callback->($link)
228 aio_realpath $path, $callback->($link)
229 aio_rename $srcpath, $dstpath, $callback->($status)
230 aio_mkdir $pathname, $mode, $callback->($status)
231 aio_rmdir $pathname, $callback->($status)
232 aio_readdir $pathname, $callback->($entries)
233 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
234 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
235 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
236 aio_load $path, $data, $callback->($status)
237 aio_copy $srcpath, $dstpath, $callback->($status)
238 aio_move $srcpath, $dstpath, $callback->($status)
239 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
240 aio_rmtree $path, $callback->($status)
241 aio_sync $callback->($status)
242 aio_fsync $fh, $callback->($status)
243 aio_fdatasync $fh, $callback->($status)
244 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
245 aio_pathsync $path, $callback->($status)
246 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
247 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
248 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
249 aio_mlockall $flags, $callback->($status)
250 aio_group $callback->(...)
251 aio_nop $callback->()
252
253 $prev_pri = aioreq_pri [$pri]
254 aioreq_nice $pri_adjust
255
256 IO::AIO::poll_wait
257 IO::AIO::poll_cb
258 IO::AIO::poll
259 IO::AIO::flush
260 IO::AIO::max_poll_reqs $nreqs
261 IO::AIO::max_poll_time $seconds
262 IO::AIO::min_parallel $nthreads
263 IO::AIO::max_parallel $nthreads
264 IO::AIO::max_idle $nthreads
265 IO::AIO::idle_timeout $seconds
266 IO::AIO::max_outstanding $maxreqs
267 IO::AIO::nreqs
268 IO::AIO::nready
269 IO::AIO::npending
270
271 IO::AIO::sendfile $ofh, $ifh, $offset, $count
272 IO::AIO::fadvise $fh, $offset, $len, $advice
273 IO::AIO::madvise $scalar, $offset, $length, $advice
274 IO::AIO::mprotect $scalar, $offset, $length, $protect
275 IO::AIO::munlock $scalar, $offset = 0, $length = undef
276 IO::AIO::munlockall
222 277
223=head2 AIO REQUEST FUNCTIONS 278=head2 AIO REQUEST FUNCTIONS
224 279
225All the C<aio_*> calls are more or less thin wrappers around the syscall 280All the C<aio_*> calls are more or less thin wrappers around the syscall
226with the same name (sans C<aio_>). The arguments are similar or identical, 281with the same name (sans C<aio_>). The arguments are similar or identical,
306by the umask in effect then the request is being executed, so better never 361by the umask in effect then the request is being executed, so better never
307change the umask. 362change the umask.
308 363
309Example: 364Example:
310 365
311 aio_open "/etc/passwd", O_RDONLY, 0, sub { 366 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
312 if ($_[0]) { 367 if ($_[0]) {
313 print "open successful, fh is $_[0]\n"; 368 print "open successful, fh is $_[0]\n";
314 ... 369 ...
315 } else { 370 } else {
316 die "open failed: $!\n"; 371 die "open failed: $!\n";
317 } 372 }
318 }; 373 };
319 374
375In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>,
376C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the
377following POSIX and non-POSIX constants are available (missing ones on
378your system are, as usual, C<0>):
379
380C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
381C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
382C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.
383
320 384
321=item aio_close $fh, $callback->($status) 385=item aio_close $fh, $callback->($status)
322 386
323Asynchronously close a file and call the callback with the result 387Asynchronously close a file and call the callback with the result
324code. 388code.
374 438
375Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts 439Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
376reading at byte offset C<$in_offset>, and starts writing at the current 440reading at byte offset C<$in_offset>, and starts writing at the current
377file offset of C<$out_fh>. Because of that, it is not safe to issue more 441file offset of C<$out_fh>. Because of that, it is not safe to issue more
378than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each 442than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
379other. 443other. The same C<$in_fh> works fine though, as this function does not
444move or use the file offset of C<$in_fh>.
380 445
446Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than
447are written, and there is no way to find out how many more bytes have been
448read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the
449number of bytes written to C<$out_fh>. Only if the result value equals
450C<$length> one can assume that C<$length> bytes have been read.
451
452Unlike with other C<aio_> functions, it makes a lot of sense to use
453C<aio_sendfile> on non-blocking sockets, as long as one end (typically
454the C<$in_fh>) is a file - the file I/O will then be asynchronous, while
455the socket I/O will be non-blocking. Note, however, that you can run
456into a trap where C<aio_sendfile> reads some data with readahead, then
457fails to write all data, and when the socket is ready the next time, the
458data in the cache is already lost, forcing C<aio_sendfile> to again hit
459the disk. Explicit C<aio_read> + C<aio_write> let's you better control
460resource usage.
461
381This call tries to make use of a native C<sendfile> syscall to provide 462This call tries to make use of a native C<sendfile>-like syscall to
382zero-copy operation. For this to work, C<$out_fh> should refer to a 463provide zero-copy operation. For this to work, C<$out_fh> should refer to
383socket, and C<$in_fh> should refer to mmap'able file. 464a socket, and C<$in_fh> should refer to an mmap'able file.
384 465
385If the native sendfile call fails or is not implemented, it will be 466If a native sendfile cannot be found or it fails with C<ENOSYS>,
386emulated, so you can call C<aio_sendfile> on any type of filehandle 467C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or
468C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any
387regardless of the limitations of the operating system. 469type of filehandle regardless of the limitations of the operating system.
388 470
389Please note, however, that C<aio_sendfile> can read more bytes from 471As native sendfile syscalls (as practically any non-POSIX interface hacked
390C<$in_fh> than are written, and there is no way to find out how many 472together in a hurry to improve benchmark numbers) tend to be rather buggy
391bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only 473on many systems, this implementation tries to work around some known bugs
392provides the number of bytes written to C<$out_fh>. Only if the result 474in Linux and FreeBSD kernels (probably others, too), but that might fail,
393value equals C<$length> one can assume that C<$length> bytes have been 475so you really really should check the return value of C<aio_sendfile> -
394read. 476fewre bytes than expected might have been transferred.
395 477
396 478
397=item aio_readahead $fh,$offset,$length, $callback->($retval) 479=item aio_readahead $fh,$offset,$length, $callback->($retval)
398 480
399C<aio_readahead> populates the page cache with data from a file so that 481C<aio_readahead> populates the page cache with data from a file so that
422 504
423Currently, the stats are always 64-bit-stats, i.e. instead of returning an 505Currently, the stats are always 64-bit-stats, i.e. instead of returning an
424error when stat'ing a large file, the results will be silently truncated 506error when stat'ing a large file, the results will be silently truncated
425unless perl itself is compiled with large file support. 507unless perl itself is compiled with large file support.
426 508
509To help interpret the mode and dev/rdev stat values, IO::AIO offers the
510following constants and functions (if not implemented, the constants will
511be C<0> and the functions will either C<croak> or fall back on traditional
512behaviour).
513
514C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
515C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
516C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
517
427Example: Print the length of F</etc/passwd>: 518Example: Print the length of F</etc/passwd>:
428 519
429 aio_stat "/etc/passwd", sub { 520 aio_stat "/etc/passwd", sub {
430 $_[0] and die "stat failed: $!"; 521 $_[0] and die "stat failed: $!";
431 print "size is ", -s _, "\n"; 522 print "size is ", -s _, "\n";
432 }; 523 };
433 524
434 525
526=item aio_statvfs $fh_or_path, $callback->($statvfs)
527
528Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
529whether a file handle or path was passed.
530
531On success, the callback is passed a hash reference with the following
532members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
533C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
534is passed.
535
536The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
537C<ST_NOSUID>.
538
539The following non-POSIX IO::AIO::ST_* flag masks are defined to
540their correct value when available, or to C<0> on systems that do
541not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
542C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
543C<ST_NODIRATIME> and C<ST_RELATIME>.
544
545Example: stat C</wd> and dump out the data if successful.
546
547 aio_statvfs "/wd", sub {
548 my $f = $_[0]
549 or die "statvfs: $!";
550
551 use Data::Dumper;
552 say Dumper $f;
553 };
554
555 # result:
556 {
557 bsize => 1024,
558 bfree => 4333064312,
559 blocks => 10253828096,
560 files => 2050765568,
561 flag => 4096,
562 favail => 2042092649,
563 bavail => 4333064312,
564 ffree => 2042092649,
565 namemax => 255,
566 frsize => 1024,
567 fsid => 1810
568 }
569
570
435=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 571=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
436 572
437Works like perl's C<utime> function (including the special case of $atime 573Works like perl's C<utime> function (including the special case of $atime
438and $mtime being undef). Fractional times are supported if the underlying 574and $mtime being undef). Fractional times are supported if the underlying
439syscalls support them. 575syscalls support them.
487 623
488The only (POSIX-) portable way of calling this function is: 624The only (POSIX-) portable way of calling this function is:
489 625
490 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... 626 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ...
491 627
628See C<aio_stat> for info about some potentially helpful extra constants
629and functions.
492 630
493=item aio_link $srcpath, $dstpath, $callback->($status) 631=item aio_link $srcpath, $dstpath, $callback->($status)
494 632
495Asynchronously create a new link to the existing object at C<$srcpath> at 633Asynchronously create a new link to the existing object at C<$srcpath> at
496the path C<$dstpath> and call the callback with the result code. 634the path C<$dstpath> and call the callback with the result code.
507Asynchronously read the symlink specified by C<$path> and pass it to 645Asynchronously read the symlink specified by C<$path> and pass it to
508the callback. If an error occurs, nothing or undef gets passed to the 646the callback. If an error occurs, nothing or undef gets passed to the
509callback. 647callback.
510 648
511 649
650=item aio_realpath $path, $callback->($path)
651
652Asynchronously make the path absolute and resolve any symlinks in
653C<$path>. The resulting path only consists of directories (Same as
654L<Cwd::realpath>).
655
656This request can be used to get the absolute path of the current working
657directory by passing it a path of F<.> (a single dot).
658
659
512=item aio_rename $srcpath, $dstpath, $callback->($status) 660=item aio_rename $srcpath, $dstpath, $callback->($status)
513 661
514Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as 662Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
515rename(2) and call the callback with the result code. 663rename(2) and call the callback with the result code.
516 664
549 697
550=over 4 698=over 4
551 699
552=item IO::AIO::READDIR_DENTS 700=item IO::AIO::READDIR_DENTS
553 701
554When this flag is off, then the callback gets an arrayref with of names 702When this flag is off, then the callback gets an arrayref consisting of
555only (as with C<aio_readdir>), otherwise it gets an arrayref with 703names only (as with C<aio_readdir>), otherwise it gets an arrayref with
556C<[$name, $type, $inode]> arrayrefs, each describing a single directory 704C<[$name, $type, $inode]> arrayrefs, each describing a single directory
557entry in more detail. 705entry in more detail.
558 706
559C<$name> is the name of the entry. 707C<$name> is the name of the entry.
560 708
573systems that do not deliver the inode information. 721systems that do not deliver the inode information.
574 722
575=item IO::AIO::READDIR_DIRS_FIRST 723=item IO::AIO::READDIR_DIRS_FIRST
576 724
577When this flag is set, then the names will be returned in an order where 725When this flag is set, then the names will be returned in an order where
578likely directories come first. This is useful when you need to quickly 726likely directories come first, in optimal stat order. This is useful when
579find directories, or you want to find all directories while avoiding to 727you need to quickly find directories, or you want to find all directories
580stat() each entry. 728while avoiding to stat() each entry.
581 729
582If the system returns type information in readdir, then this is used 730If the system returns type information in readdir, then this is used
583to find directories directly. Otherwise, likely directories are files 731to find directories directly. Otherwise, likely directories are names
584beginning with ".", or otherwise files with no dots, of which files with 732beginning with ".", or otherwise names with no dots, of which names with
585short names are tried first. 733short names are tried first.
586 734
587=item IO::AIO::READDIR_STAT_ORDER 735=item IO::AIO::READDIR_STAT_ORDER
588 736
589When this flag is set, then the names will be returned in an order 737When this flag is set, then the names will be returned in an order
634 782
635=item aio_copy $srcpath, $dstpath, $callback->($status) 783=item aio_copy $srcpath, $dstpath, $callback->($status)
636 784
637Try to copy the I<file> (directories not supported as either source or 785Try to copy the I<file> (directories not supported as either source or
638destination) from C<$srcpath> to C<$dstpath> and call the callback with 786destination) from C<$srcpath> to C<$dstpath> and call the callback with
639the C<0> (error) or C<-1> ok. 787a status of C<0> (ok) or C<-1> (error, see C<$!>).
640 788
641This is a composite request that creates the destination file with 789This is a composite request that creates the destination file with
642mode 0200 and copies the contents of the source file into it using 790mode 0200 and copies the contents of the source file into it using
643C<aio_sendfile>, followed by restoring atime, mtime, access mode and 791C<aio_sendfile>, followed by restoring atime, mtime, access mode and
644uid/gid, in that order. 792uid/gid, in that order.
656 my $grp = aio_group $cb; 804 my $grp = aio_group $cb;
657 805
658 aioreq_pri $pri; 806 aioreq_pri $pri;
659 add $grp aio_open $src, O_RDONLY, 0, sub { 807 add $grp aio_open $src, O_RDONLY, 0, sub {
660 if (my $src_fh = $_[0]) { 808 if (my $src_fh = $_[0]) {
661 my @stat = stat $src_fh; # hmm, might bock over nfs? 809 my @stat = stat $src_fh; # hmm, might block over nfs?
662 810
663 aioreq_pri $pri; 811 aioreq_pri $pri;
664 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { 812 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {
665 if (my $dst_fh = $_[0]) { 813 if (my $dst_fh = $_[0]) {
666 aioreq_pri $pri; 814 aioreq_pri $pri;
713 861
714=item aio_move $srcpath, $dstpath, $callback->($status) 862=item aio_move $srcpath, $dstpath, $callback->($status)
715 863
716Try to move the I<file> (directories not supported as either source or 864Try to move the I<file> (directories not supported as either source or
717destination) from C<$srcpath> to C<$dstpath> and call the callback with 865destination) from C<$srcpath> to C<$dstpath> and call the callback with
718the C<0> (error) or C<-1> ok. 866a status of C<0> (ok) or C<-1> (error, see C<$!>).
719 867
720This is a composite request that tries to rename(2) the file first; if 868This is a composite request that tries to rename(2) the file first; if
721rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if 869rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
722that is successful, unlinks the C<$srcpath>. 870that is successful, unlinks the C<$srcpath>.
723 871
734 if ($_[0] && $! == EXDEV) { 882 if ($_[0] && $! == EXDEV) {
735 aioreq_pri $pri; 883 aioreq_pri $pri;
736 add $grp aio_copy $src, $dst, sub { 884 add $grp aio_copy $src, $dst, sub {
737 $grp->result ($_[0]); 885 $grp->result ($_[0]);
738 886
739 if (!$_[0]) { 887 unless ($_[0]) {
740 aioreq_pri $pri; 888 aioreq_pri $pri;
741 add $grp aio_unlink $src; 889 add $grp aio_unlink $src;
742 } 890 }
743 }; 891 };
744 } else { 892 } else {
989 }; 1137 };
990 1138
991 $grp 1139 $grp
992} 1140}
993 1141
1142=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1143
1144This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1145scalars (see the C<IO::AIO::mmap> function, although it also works on data
1146scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1147scalar must only be modified in-place while an aio operation is pending on
1148it).
1149
1150It calls the C<msync> function of your OS, if available, with the memory
1151area starting at C<$offset> in the string and ending C<$length> bytes
1152later. If C<$length> is negative, counts from the end, and if C<$length>
1153is C<undef>, then it goes till the end of the string. The flags can be
1154a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
1155C<IO::AIO::MS_SYNC>.
1156
1157=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1158
1159This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1160scalars.
1161
1162It touches (reads or writes) all memory pages in the specified
1163range inside the scalar. All caveats and parameters are the same
1164as for C<aio_msync>, above, except for flags, which must be either
1165C<0> (which reads all pages and ensures they are instantiated) or
1166C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
1167writing an octet from it, which dirties the page).
1168
1169=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1170
1171This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1172scalars.
1173
1174It reads in all the pages of the underlying storage into memory (if any)
1175and locks them, so they are not getting swapped/paged out or removed.
1176
1177If C<$length> is undefined, then the scalar will be locked till the end.
1178
1179On systems that do not implement C<mlock>, this function returns C<-1>
1180and sets errno to C<ENOSYS>.
1181
1182Note that the corresponding C<munlock> is synchronous and is
1183documented under L<MISCELLANEOUS FUNCTIONS>.
1184
1185Example: open a file, mmap and mlock it - both will be undone when
1186C<$data> gets destroyed.
1187
1188 open my $fh, "<", $path or die "$path: $!";
1189 my $data;
1190 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1191 aio_mlock $data; # mlock in background
1192
1193=item aio_mlockall $flags, $callback->($status)
1194
1195Calls the C<mlockall> function with the given C<$flags> (a combination of
1196C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).
1197
1198On systems that do not implement C<mlockall>, this function returns C<-1>
1199and sets errno to C<ENOSYS>.
1200
1201Note that the corresponding C<munlockall> is synchronous and is
1202documented under L<MISCELLANEOUS FUNCTIONS>.
1203
1204Example: asynchronously lock all current and future pages into memory.
1205
1206 aio_mlockall IO::AIO::MCL_FUTURE;
1207
994=item aio_group $callback->(...) 1208=item aio_group $callback->(...)
995 1209
996This is a very special aio request: Instead of doing something, it is a 1210This is a very special aio request: Instead of doing something, it is a
997container for other aio requests, which is useful if you want to bundle 1211container for other aio requests, which is useful if you want to bundle
998many requests into a single, composite, request with a definite callback 1212many requests into a single, composite, request with a definite callback
1133=item $grp->cancel_subs 1347=item $grp->cancel_subs
1134 1348
1135Cancel all subrequests and clears any feeder, but not the group request 1349Cancel all subrequests and clears any feeder, but not the group request
1136itself. Useful when you queued a lot of events but got a result early. 1350itself. Useful when you queued a lot of events but got a result early.
1137 1351
1352The group request will finish normally (you cannot add requests to the
1353group).
1354
1138=item $grp->result (...) 1355=item $grp->result (...)
1139 1356
1140Set the result value(s) that will be passed to the group callback when all 1357Set the result value(s) that will be passed to the group callback when all
1141subrequests have finished and set the groups errno to the current value 1358subrequests have finished and set the groups errno to the current value
1142of errno (just like calling C<errno> without an error number). By default, 1359of errno (just like calling C<errno> without an error number). By default,
1218 1435
1219See C<poll_cb> for an example. 1436See C<poll_cb> for an example.
1220 1437
1221=item IO::AIO::poll_cb 1438=item IO::AIO::poll_cb
1222 1439
1223Process some outstanding events on the result pipe. You have to call this 1440Process some outstanding events on the result pipe. You have to call
1224regularly. Returns C<0> if all events could be processed, or C<-1> if it 1441this regularly. Returns C<0> if all events could be processed (or there
1225returned earlier for whatever reason. Returns immediately when no events 1442were no events to process), or C<-1> if it returned earlier for whatever
1226are outstanding. The amount of events processed depends on the settings of 1443reason. Returns immediately when no events are outstanding. The amount of
1227C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. 1444events processed depends on the settings of C<IO::AIO::max_poll_req> and
1445C<IO::AIO::max_poll_time>.
1228 1446
1229If not all requests were processed for whatever reason, the filehandle 1447If not all requests were processed for whatever reason, the filehandle
1230will still be ready when C<poll_cb> returns, so normally you don't have to 1448will still be ready when C<poll_cb> returns, so normally you don't have to
1231do anything special to have it called later. 1449do anything special to have it called later.
1232 1450
1451Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1452ready, it can be beneficial to call this function from loops which submit
1453a lot of requests, to make sure the results get processed when they become
1454available and not just when the loop is finished and the event loop takes
1455over again. This function returns very fast when there are no outstanding
1456requests.
1457
1233Example: Install an Event watcher that automatically calls 1458Example: Install an Event watcher that automatically calls
1234IO::AIO::poll_cb with high priority (more examples can be found in the 1459IO::AIO::poll_cb with high priority (more examples can be found in the
1235SYNOPSIS section, at the top of this document): 1460SYNOPSIS section, at the top of this document):
1236 1461
1237 Event->io (fd => IO::AIO::poll_fileno, 1462 Event->io (fd => IO::AIO::poll_fileno,
1238 poll => 'r', async => 1, 1463 poll => 'r', async => 1,
1239 cb => \&IO::AIO::poll_cb); 1464 cb => \&IO::AIO::poll_cb);
1465
1466=item IO::AIO::poll_wait
1467
1468If there are any outstanding requests and none of them in the result
1469phase, wait till the result filehandle becomes ready for reading (simply
1470does a C<select> on the filehandle. This is useful if you want to
1471synchronously wait for some requests to finish).
1472
1473See C<nreqs> for an example.
1474
1475=item IO::AIO::poll
1476
1477Waits until some requests have been handled.
1478
1479Returns the number of requests processed, but is otherwise strictly
1480equivalent to:
1481
1482 IO::AIO::poll_wait, IO::AIO::poll_cb
1483
1484=item IO::AIO::flush
1485
1486Wait till all outstanding AIO requests have been handled.
1487
1488Strictly equivalent to:
1489
1490 IO::AIO::poll_wait, IO::AIO::poll_cb
1491 while IO::AIO::nreqs;
1240 1492
1241=item IO::AIO::max_poll_reqs $nreqs 1493=item IO::AIO::max_poll_reqs $nreqs
1242 1494
1243=item IO::AIO::max_poll_time $seconds 1495=item IO::AIO::max_poll_time $seconds
1244 1496
1269 # use a low priority so other tasks have priority 1521 # use a low priority so other tasks have priority
1270 Event->io (fd => IO::AIO::poll_fileno, 1522 Event->io (fd => IO::AIO::poll_fileno,
1271 poll => 'r', nice => 1, 1523 poll => 'r', nice => 1,
1272 cb => &IO::AIO::poll_cb); 1524 cb => &IO::AIO::poll_cb);
1273 1525
1274=item IO::AIO::poll_wait
1275
1276If there are any outstanding requests and none of them in the result
1277phase, wait till the result filehandle becomes ready for reading (simply
1278does a C<select> on the filehandle. This is useful if you want to
1279synchronously wait for some requests to finish).
1280
1281See C<nreqs> for an example.
1282
1283=item IO::AIO::poll
1284
1285Waits until some requests have been handled.
1286
1287Returns the number of requests processed, but is otherwise strictly
1288equivalent to:
1289
1290 IO::AIO::poll_wait, IO::AIO::poll_cb
1291
1292=item IO::AIO::flush
1293
1294Wait till all outstanding AIO requests have been handled.
1295
1296Strictly equivalent to:
1297
1298 IO::AIO::poll_wait, IO::AIO::poll_cb
1299 while IO::AIO::nreqs;
1300
1301=back 1526=back
1302 1527
1303=head3 CONTROLLING THE NUMBER OF THREADS 1528=head3 CONTROLLING THE NUMBER OF THREADS
1304 1529
1305=over 1530=over
1338 1563
1339Under normal circumstances you don't need to call this function. 1564Under normal circumstances you don't need to call this function.
1340 1565
1341=item IO::AIO::max_idle $nthreads 1566=item IO::AIO::max_idle $nthreads
1342 1567
1343Limit the number of threads (default: 4) that are allowed to idle (i.e., 1568Limit the number of threads (default: 4) that are allowed to idle
1344threads that did not get a request to process within 10 seconds). That 1569(i.e., threads that did not get a request to process within the idle
1345means if a thread becomes idle while C<$nthreads> other threads are also 1570timeout (default: 10 seconds). That means if a thread becomes idle while
1346idle, it will free its resources and exit. 1571C<$nthreads> other threads are also idle, it will free its resources and
1572exit.
1347 1573
1348This is useful when you allow a large number of threads (e.g. 100 or 1000) 1574This is useful when you allow a large number of threads (e.g. 100 or 1000)
1349to allow for extremely high load situations, but want to free resources 1575to allow for extremely high load situations, but want to free resources
1350under normal circumstances (1000 threads can easily consume 30MB of RAM). 1576under normal circumstances (1000 threads can easily consume 30MB of RAM).
1351 1577
1352The default is probably ok in most situations, especially if thread 1578The default is probably ok in most situations, especially if thread
1353creation is fast. If thread creation is very slow on your system you might 1579creation is fast. If thread creation is very slow on your system you might
1354want to use larger values. 1580want to use larger values.
1355 1581
1582=item IO::AIO::idle_timeout $seconds
1583
1584Sets the minimum idle timeout (default 10) after which worker threads are
1585allowed to exit. SEe C<IO::AIO::max_idle>.
1586
1356=item IO::AIO::max_outstanding $maxreqs 1587=item IO::AIO::max_outstanding $maxreqs
1588
1589Sets the maximum number of outstanding requests to C<$nreqs>. If
1590you do queue up more than this number of requests, the next call to
1591C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as
1592C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no
1593longer exceeded.
1594
1595In other words, this setting does not enforce a queue limit, but can be
1596used to make poll functions block if the limit is exceeded.
1357 1597
1358This is a very bad function to use in interactive programs because it 1598This is a very bad function to use in interactive programs because it
1359blocks, and a bad way to reduce concurrency because it is inexact: Better 1599blocks, and a bad way to reduce concurrency because it is inexact: Better
1360use an C<aio_group> together with a feed callback. 1600use an C<aio_group> together with a feed callback.
1361 1601
1362Sets the maximum number of outstanding requests to C<$nreqs>. If you 1602It's main use is in scripts without an event loop - when you want to stat
1363do queue up more than this number of requests, the next call to the 1603a lot of files, you can write somehting like this:
1364C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1365function will block until the limit is no longer exceeded.
1366 1604
1367The default value is very large, so there is no practical limit on the 1605 IO::AIO::max_outstanding 32;
1368number of outstanding requests.
1369 1606
1370You can still queue as many requests as you want. Therefore, 1607 for my $path (...) {
1371C<max_outstanding> is mainly useful in simple scripts (with low values) or 1608 aio_stat $path , ...;
1372as a stop gap to shield against fatal memory overflow (with large values). 1609 IO::AIO::poll_cb;
1610 }
1611
1612 IO::AIO::flush;
1613
1614The call to C<poll_cb> inside the loop will normally return instantly, but
1615as soon as more thna C<32> reqeusts are in-flight, it will block until
1616some requests have been handled. This keeps the loop from pushing a large
1617number of C<aio_stat> requests onto the queue.
1618
1619The default value for C<max_outstanding> is very large, so there is no
1620practical limit on the number of outstanding requests.
1373 1621
1374=back 1622=back
1375 1623
1376=head3 STATISTICAL INFORMATION 1624=head3 STATISTICAL INFORMATION
1377 1625
1415 1663
1416Returns the number of bytes copied, or C<-1> on error. 1664Returns the number of bytes copied, or C<-1> on error.
1417 1665
1418=item IO::AIO::fadvise $fh, $offset, $len, $advice 1666=item IO::AIO::fadvise $fh, $offset, $len, $advice
1419 1667
1420Simply calls the C<posix_fadvise> function (see it's 1668Simply calls the C<posix_fadvise> function (see its
1421manpage for details). The following advice constants are 1669manpage for details). The following advice constants are
1422avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, 1670avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1423C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, 1671C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1424C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. 1672C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1425 1673
1426On systems that do not implement C<posix_fadvise>, this function returns 1674On systems that do not implement C<posix_fadvise>, this function returns
1427ENOSYS, otherwise the return value of C<posix_fadvise>. 1675ENOSYS, otherwise the return value of C<posix_fadvise>.
1428 1676
1677=item IO::AIO::madvise $scalar, $offset, $len, $advice
1678
1679Simply calls the C<posix_madvise> function (see its
1680manpage for details). The following advice constants are
1681avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1682C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1683
1684On systems that do not implement C<posix_madvise>, this function returns
1685ENOSYS, otherwise the return value of C<posix_madvise>.
1686
1687=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1688
1689Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1690$scalar (see its manpage for details). The following protect
1691constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1692C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1693
1694On systems that do not implement C<mprotect>, this function returns
1695ENOSYS, otherwise the return value of C<mprotect>.
1696
1697=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1698
1699Memory-maps a file (or anonymous memory range) and attaches it to the
1700given C<$scalar>, which will act like a string scalar.
1701
1702The only operations allowed on the scalar are C<substr>/C<vec> that don't
1703change the string length, and most read-only operations such as copying it
1704or searching it with regexes and so on.
1705
1706Anything else is unsafe and will, at best, result in memory leaks.
1707
1708The memory map associated with the C<$scalar> is automatically removed
1709when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
1710C<IO::AIO::munmap> functions are called.
1711
1712This calls the C<mmap>(2) function internally. See your system's manual
1713page for details on the C<$length>, C<$prot> and C<$flags> parameters.
1714
1715The C<$length> must be larger than zero and smaller than the actual
1716filesize.
1717
1718C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1719C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1720
1721C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
1722C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
1723not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
1724(which is set to C<MAP_ANON> if your system only provides this
1725constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
1726C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
1727C<IO::AIO::MAP_NONBLOCK>
1728
1729If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1730
1731C<$offset> is the offset from the start of the file - it generally must be
1732a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
1733
1734Example:
1735
1736 use Digest::MD5;
1737 use IO::AIO;
1738
1739 open my $fh, "<verybigfile"
1740 or die "$!";
1741
1742 IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
1743 or die "verybigfile: $!";
1744
1745 my $fast_md5 = md5 $data;
1746
1747=item IO::AIO::munmap $scalar
1748
1749Removes a previous mmap and undefines the C<$scalar>.
1750
1751=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
1752
1753Calls the C<munlock> function, undoing the effects of a previous
1754C<aio_mlock> call (see its description for details).
1755
1756=item IO::AIO::munlockall
1757
1758Calls the C<munlockall> function.
1759
1760On systems that do not implement C<munlockall>, this function returns
1761ENOSYS, otherwise the return value of C<munlockall>.
1762
1429=back 1763=back
1430 1764
1431=cut 1765=cut
1432 1766
1433min_parallel 8; 1767min_parallel 8;
1434 1768
1435END { flush } 1769END { flush }
1436 1770
14371; 17711;
1438 1772
1773=head1 EVENT LOOP INTEGRATION
1774
1775It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
1776automatically into many event loops:
1777
1778 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
1779 use AnyEvent::AIO;
1780
1781You can also integrate IO::AIO manually into many event loops, here are
1782some examples of how to do this:
1783
1784 # EV integration
1785 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
1786
1787 # Event integration
1788 Event->io (fd => IO::AIO::poll_fileno,
1789 poll => 'r',
1790 cb => \&IO::AIO::poll_cb);
1791
1792 # Glib/Gtk2 integration
1793 add_watch Glib::IO IO::AIO::poll_fileno,
1794 in => sub { IO::AIO::poll_cb; 1 };
1795
1796 # Tk integration
1797 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
1798 readable => \&IO::AIO::poll_cb);
1799
1800 # Danga::Socket integration
1801 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
1802 \&IO::AIO::poll_cb);
1803
1439=head2 FORK BEHAVIOUR 1804=head2 FORK BEHAVIOUR
1440 1805
1441This module should do "the right thing" when the process using it forks: 1806Usage of pthreads in a program changes the semantics of fork
1807considerably. Specifically, only async-safe functions can be called after
1808fork. Perl doesn't know about this, so in general, you cannot call fork
1809with defined behaviour in perl. IO::AIO uses pthreads, so this applies,
1810but many other extensions and (for inexplicable reasons) perl itself often
1811is linked against pthreads, so this limitation applies.
1442 1812
1443Before the fork, IO::AIO enters a quiescent state where no requests 1813Some operating systems have extensions that allow safe use of fork, and
1444can be added in other threads and no results will be processed. After 1814this module should do "the right thing" on those, and tries on others. At
1445the fork the parent simply leaves the quiescent state and continues 1815the time of this writing (2011) only GNU/Linux supports these extensions
1446request/result processing, while the child frees the request/result queue 1816to POSIX.
1447(so that the requests started before the fork will only be handled in the
1448parent). Threads will be started on demand until the limit set in the
1449parent process has been reached again.
1450
1451In short: the parent will, after a short pause, continue as if fork had
1452not been called, while the child will act as if IO::AIO has not been used
1453yet.
1454 1817
1455=head2 MEMORY USAGE 1818=head2 MEMORY USAGE
1456 1819
1457Per-request usage: 1820Per-request usage:
1458 1821

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines