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 1.172 by root, Thu Jan 7 18:08:21 2010 UTC vs.
Revision 1.191 by root, Thu May 19 23:57:12 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 = '3.4'; 173 our $VERSION = '3.8';
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_sync aio_fsync
201 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead 178 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
202 aio_rename aio_link aio_move aio_copy aio_group 179 aio_rename aio_link aio_move aio_copy aio_group
203 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
204 aio_chmod aio_utime aio_truncate 181 aio_chmod aio_utime aio_truncate
205 aio_msync aio_mtouch aio_statvfs); 182 aio_msync aio_mtouch aio_mlock aio_mlockall
183 aio_statvfs);
206 184
207 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 185 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
208 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 186 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
209 min_parallel max_parallel max_idle 187 min_parallel max_parallel max_idle idle_timeout
210 nreqs nready npending nthreads 188 nreqs nready npending nthreads
211 max_poll_time max_poll_reqs 189 max_poll_time max_poll_reqs
212 sendfile fadvise); 190 sendfile fadvise madvise
191 mmap munmap munlock munlockall);
213 192
214 push @AIO_REQ, qw(aio_busy); # not exported 193 push @AIO_REQ, qw(aio_busy); # not exported
215 194
216 @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; 195 @IO::AIO::GRP::ISA = 'IO::AIO::REQ';
217 196
218 require XSLoader; 197 require XSLoader;
219 XSLoader::load ("IO::AIO", $VERSION); 198 XSLoader::load ("IO::AIO", $VERSION);
220} 199}
221 200
222=head1 FUNCTIONS 201=head1 FUNCTIONS
202
203=head2 QUICK OVERVIEW
204
205This section simply lists the prototypes of the most important functions
206for quick reference. See the following sections for function-by-function
207documentation.
208
209 aio_open $pathname, $flags, $mode, $callback->($fh)
210 aio_close $fh, $callback->($status)
211 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
212 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
214 aio_readahead $fh,$offset,$length, $callback->($retval)
215 aio_stat $fh_or_path, $callback->($status)
216 aio_lstat $fh, $callback->($status)
217 aio_statvfs $fh_or_path, $callback->($statvfs)
218 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
219 aio_chown $fh_or_path, $uid, $gid, $callback->($status)
220 aio_truncate $fh_or_path, $offset, $callback->($status)
221 aio_chmod $fh_or_path, $mode, $callback->($status)
222 aio_unlink $pathname, $callback->($status)
223 aio_mknod $path, $mode, $dev, $callback->($status)
224 aio_link $srcpath, $dstpath, $callback->($status)
225 aio_symlink $srcpath, $dstpath, $callback->($status)
226 aio_readlink $path, $callback->($link)
227 aio_rename $srcpath, $dstpath, $callback->($status)
228 aio_mkdir $pathname, $mode, $callback->($status)
229 aio_rmdir $pathname, $callback->($status)
230 aio_readdir $pathname, $callback->($entries)
231 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
232 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
233 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
234 aio_load $path, $data, $callback->($status)
235 aio_copy $srcpath, $dstpath, $callback->($status)
236 aio_move $srcpath, $dstpath, $callback->($status)
237 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
238 aio_rmtree $path, $callback->($status)
239 aio_sync $callback->($status)
240 aio_fsync $fh, $callback->($status)
241 aio_fdatasync $fh, $callback->($status)
242 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
243 aio_pathsync $path, $callback->($status)
244 aio_msync $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)
248 aio_group $callback->(...)
249 aio_nop $callback->()
250
251 $prev_pri = aioreq_pri [$pri]
252 aioreq_nice $pri_adjust
253
254 IO::AIO::poll_wait
255 IO::AIO::poll_cb
256 IO::AIO::poll
257 IO::AIO::flush
258 IO::AIO::max_poll_reqs $nreqs
259 IO::AIO::max_poll_time $seconds
260 IO::AIO::min_parallel $nthreads
261 IO::AIO::max_parallel $nthreads
262 IO::AIO::max_idle $nthreads
263 IO::AIO::idle_timeout $seconds
264 IO::AIO::max_outstanding $maxreqs
265 IO::AIO::nreqs
266 IO::AIO::nready
267 IO::AIO::npending
268
269 IO::AIO::sendfile $ofh, $ifh, $offset, $count
270 IO::AIO::fadvise $fh, $offset, $len, $advice
271 IO::AIO::madvise $scalar, $offset, $length, $advice
272 IO::AIO::mprotect $scalar, $offset, $length, $protect
273 IO::AIO::munlock $scalar, $offset = 0, $length = undef
274 IO::AIO::munlockall
223 275
224=head2 AIO REQUEST FUNCTIONS 276=head2 AIO REQUEST FUNCTIONS
225 277
226All the C<aio_*> calls are more or less thin wrappers around the syscall 278All the C<aio_*> calls are more or less thin wrappers around the syscall
227with the same name (sans C<aio_>). The arguments are similar or identical, 279with the same name (sans C<aio_>). The arguments are similar or identical,
… …
307by the umask in effect then the request is being executed, so better never 359by the umask in effect then the request is being executed, so better never
308change the umask. 360change the umask.
309 361
310Example: 362Example:
311 363
312 aio_open "/etc/passwd", O_RDONLY, 0, sub { 364 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
313 if ($_[0]) { 365 if ($_[0]) {
314 print "open successful, fh is $_[0]\n"; 366 print "open successful, fh is $_[0]\n";
315 ... 367 ...
316 } else { 368 } else {
317 die "open failed: $!\n"; 369 die "open failed: $!\n";
… …
377reading at byte offset C<$in_offset>, and starts writing at the current 429reading at byte offset C<$in_offset>, and starts writing at the current
378file offset of C<$out_fh>. Because of that, it is not safe to issue more 430file offset of C<$out_fh>. Because of that, it is not safe to issue more
379than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each 431than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
380other. 432other.
381 433
434Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than
435are written, and there is no way to find out how many bytes have been read
436from C<aio_sendfile> alone, as C<aio_sendfile> only provides the number of
437bytes written to C<$out_fh>. Only if the result value equals C<$length>
438one can assume that C<$length> bytes have been read.
439
440Unlike with other C<aio_> functions, it makes a lot of sense to use
441C<aio_sendfile> on non-blocking sockets, as long as one end (typically
442the C<$in_fh>) is a file - the file I/O will then be asynchronous, while
443the socket I/O will be non-blocking. Note, however, that you can run into
444a trap where C<aio_sendfile> reads some data with readahead, then fails
445to write all data, and when the socket is ready the next time, the data
446in the cache is already lost, forcing C<aio_sendfile> to again hit the
447disk. Explicit C<aio_read> + C<aio_write> let's you control resource usage
448much better.
449
382This call tries to make use of a native C<sendfile> syscall to provide 450This call tries to make use of a native C<sendfile> syscall to provide
383zero-copy operation. For this to work, C<$out_fh> should refer to a 451zero-copy operation. For this to work, C<$out_fh> should refer to a
384socket, and C<$in_fh> should refer to mmap'able file. 452socket, and C<$in_fh> should refer to an mmap'able file.
385 453
386If a native sendfile cannot be found or it fails with C<ENOSYS>, 454If a native sendfile cannot be found or it fails with C<ENOSYS>,
387C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>, 455C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
388it will be emulated, so you can call C<aio_sendfile> on any type of 456it will be emulated, so you can call C<aio_sendfile> on any type of
389filehandle regardless of the limitations of the operating system. 457filehandle regardless of the limitations of the operating system.
390
391Please note, however, that C<aio_sendfile> can read more bytes from
392C<$in_fh> than are written, and there is no way to find out how many
393bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
394provides the number of bytes written to C<$out_fh>. Only if the result
395value equals C<$length> one can assume that C<$length> bytes have been
396read.
397 458
398 459
399=item aio_readahead $fh,$offset,$length, $callback->($retval) 460=item aio_readahead $fh,$offset,$length, $callback->($retval)
400 461
401C<aio_readahead> populates the page cache with data from a file so that 462C<aio_readahead> populates the page cache with data from a file so that
… …
424 485
425Currently, the stats are always 64-bit-stats, i.e. instead of returning an 486Currently, the stats are always 64-bit-stats, i.e. instead of returning an
426error when stat'ing a large file, the results will be silently truncated 487error when stat'ing a large file, the results will be silently truncated
427unless perl itself is compiled with large file support. 488unless perl itself is compiled with large file support.
428 489
490To help interpret the mode and dev/rdev stat values, IO::AIO offers the
491following constants and functions (if not implemented, the constants will
492be C<0> and the functions will either C<croak> or fall back on traditional
493behaviour).
494
495C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
496C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
497C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
498
429Example: Print the length of F</etc/passwd>: 499Example: Print the length of F</etc/passwd>:
430 500
431 aio_stat "/etc/passwd", sub { 501 aio_stat "/etc/passwd", sub {
432 $_[0] and die "stat failed: $!"; 502 $_[0] and die "stat failed: $!";
433 print "size is ", -s _, "\n"; 503 print "size is ", -s _, "\n";
434 }; 504 };
435 505
436 506
437=item aio_statvfs $fh_or_path, $callback->($statvfs) 507=item aio_statvfs $fh_or_path, $callback->($statvfs)
438 508
439Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on 509Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
440whether a file handle or path was passed. 510whether a file handle or path was passed.
441 511
442On success, the callback is passed a hash reference with the following 512On success, the callback is passed a hash reference with the following
… …
534 604
535The only (POSIX-) portable way of calling this function is: 605The only (POSIX-) portable way of calling this function is:
536 606
537 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... 607 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ...
538 608
609See C<aio_stat> for info about some potentially helpful extra constants
610and functions.
539 611
540=item aio_link $srcpath, $dstpath, $callback->($status) 612=item aio_link $srcpath, $dstpath, $callback->($status)
541 613
542Asynchronously create a new link to the existing object at C<$srcpath> at 614Asynchronously create a new link to the existing object at C<$srcpath> at
543the path C<$dstpath> and call the callback with the result code. 615the path C<$dstpath> and call the callback with the result code.
… …
596 668
597=over 4 669=over 4
598 670
599=item IO::AIO::READDIR_DENTS 671=item IO::AIO::READDIR_DENTS
600 672
601When this flag is off, then the callback gets an arrayref with of names 673When this flag is off, then the callback gets an arrayref consisting of
602only (as with C<aio_readdir>), otherwise it gets an arrayref with 674names only (as with C<aio_readdir>), otherwise it gets an arrayref with
603C<[$name, $type, $inode]> arrayrefs, each describing a single directory 675C<[$name, $type, $inode]> arrayrefs, each describing a single directory
604entry in more detail. 676entry in more detail.
605 677
606C<$name> is the name of the entry. 678C<$name> is the name of the entry.
607 679
… …
1039} 1111}
1040 1112
1041=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 1113=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1042 1114
1043This is a rather advanced IO::AIO call, which only works on mmap(2)ed 1115This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1044scalars (see the L<Sys::Mmap> or L<Mmap> modules for details on this, note 1116scalars (see the C<IO::AIO::mmap> function, although it also works on data
1117scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1045that the scalar must only be modified in-place while an aio operation is 1118scalar must only be modified in-place while an aio operation is pending on
1046pending on it). 1119it).
1047 1120
1048It calls the C<msync> function of your OS, if available, with the memory 1121It calls the C<msync> function of your OS, if available, with the memory
1049area starting at C<$offset> in the string and ending C<$length> bytes 1122area starting at C<$offset> in the string and ending C<$length> bytes
1050later. If C<$length> is negative, counts from the end, and if C<$length> 1123later. If C<$length> is negative, counts from the end, and if C<$length>
1051is C<undef>, then it goes till the end of the string. The flags can be 1124is C<undef>, then it goes till the end of the string. The flags can be
… …
1062as for C<aio_msync>, above, except for flags, which must be either 1135as for C<aio_msync>, above, except for flags, which must be either
1063C<0> (which reads all pages and ensures they are instantiated) or 1136C<0> (which reads all pages and ensures they are instantiated) or
1064C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and 1137C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
1065writing an octet from it, which dirties the page). 1138writing an octet from it, which dirties the page).
1066 1139
1140=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1141
1142This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1143scalars.
1144
1145It reads in all the pages of the underlying storage into memory (if any)
1146and locks them, so they are not getting swapped/paged out or removed.
1147
1148If C<$length> is undefined, then the scalar will be locked till the end.
1149
1150On systems that do not implement C<mlock>, this function returns C<-1>
1151and sets errno to C<ENOSYS>.
1152
1153Note that the corresponding C<munlock> is synchronous and is
1154documented under L<MISCELLANEOUS FUNCTIONS>.
1155
1156Example: open a file, mmap and mlock it - both will be undone when
1157C<$data> gets destroyed.
1158
1159 open my $fh, "<", $path or die "$path: $!";
1160 my $data;
1161 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1162 aio_mlock $data; # mlock in background
1163
1164=item aio_mlockall $flags, $callback->($status)
1165
1166Calls the C<mlockall> function with the given C<$flags> (a combination of
1167C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).
1168
1169On systems that do not implement C<mlockall>, this function returns C<-1>
1170and sets errno to C<ENOSYS>.
1171
1172Note that the corresponding C<munlockall> is synchronous and is
1173documented under L<MISCELLANEOUS FUNCTIONS>.
1174
1175Example: asynchronously lock all current and future pages into memory.
1176
1177 aio_mlockall IO::AIO::MCL_FUTURE;
1178
1067=item aio_group $callback->(...) 1179=item aio_group $callback->(...)
1068 1180
1069This is a very special aio request: Instead of doing something, it is a 1181This is a very special aio request: Instead of doing something, it is a
1070container for other aio requests, which is useful if you want to bundle 1182container for other aio requests, which is useful if you want to bundle
1071many requests into a single, composite, request with a definite callback 1183many requests into a single, composite, request with a definite callback
… …
1294 1406
1295See C<poll_cb> for an example. 1407See C<poll_cb> for an example.
1296 1408
1297=item IO::AIO::poll_cb 1409=item IO::AIO::poll_cb
1298 1410
1299Process some outstanding events on the result pipe. You have to call this 1411Process some outstanding events on the result pipe. You have to call
1300regularly. Returns C<0> if all events could be processed, or C<-1> if it 1412this regularly. Returns C<0> if all events could be processed (or there
1301returned earlier for whatever reason. Returns immediately when no events 1413were no events to process), or C<-1> if it returned earlier for whatever
1302are outstanding. The amount of events processed depends on the settings of 1414reason. Returns immediately when no events are outstanding. The amount of
1303C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. 1415events processed depends on the settings of C<IO::AIO::max_poll_req> and
1416C<IO::AIO::max_poll_time>.
1304 1417
1305If not all requests were processed for whatever reason, the filehandle 1418If not all requests were processed for whatever reason, the filehandle
1306will still be ready when C<poll_cb> returns, so normally you don't have to 1419will still be ready when C<poll_cb> returns, so normally you don't have to
1307do anything special to have it called later. 1420do anything special to have it called later.
1308 1421
… …
1311SYNOPSIS section, at the top of this document): 1424SYNOPSIS section, at the top of this document):
1312 1425
1313 Event->io (fd => IO::AIO::poll_fileno, 1426 Event->io (fd => IO::AIO::poll_fileno,
1314 poll => 'r', async => 1, 1427 poll => 'r', async => 1,
1315 cb => \&IO::AIO::poll_cb); 1428 cb => \&IO::AIO::poll_cb);
1429
1430=item IO::AIO::poll_wait
1431
1432If there are any outstanding requests and none of them in the result
1433phase, wait till the result filehandle becomes ready for reading (simply
1434does a C<select> on the filehandle. This is useful if you want to
1435synchronously wait for some requests to finish).
1436
1437See C<nreqs> for an example.
1438
1439=item IO::AIO::poll
1440
1441Waits until some requests have been handled.
1442
1443Returns the number of requests processed, but is otherwise strictly
1444equivalent to:
1445
1446 IO::AIO::poll_wait, IO::AIO::poll_cb
1447
1448=item IO::AIO::flush
1449
1450Wait till all outstanding AIO requests have been handled.
1451
1452Strictly equivalent to:
1453
1454 IO::AIO::poll_wait, IO::AIO::poll_cb
1455 while IO::AIO::nreqs;
1316 1456
1317=item IO::AIO::max_poll_reqs $nreqs 1457=item IO::AIO::max_poll_reqs $nreqs
1318 1458
1319=item IO::AIO::max_poll_time $seconds 1459=item IO::AIO::max_poll_time $seconds
1320 1460
… …
1345 # use a low priority so other tasks have priority 1485 # use a low priority so other tasks have priority
1346 Event->io (fd => IO::AIO::poll_fileno, 1486 Event->io (fd => IO::AIO::poll_fileno,
1347 poll => 'r', nice => 1, 1487 poll => 'r', nice => 1,
1348 cb => &IO::AIO::poll_cb); 1488 cb => &IO::AIO::poll_cb);
1349 1489
1350=item IO::AIO::poll_wait
1351
1352If there are any outstanding requests and none of them in the result
1353phase, wait till the result filehandle becomes ready for reading (simply
1354does a C<select> on the filehandle. This is useful if you want to
1355synchronously wait for some requests to finish).
1356
1357See C<nreqs> for an example.
1358
1359=item IO::AIO::poll
1360
1361Waits until some requests have been handled.
1362
1363Returns the number of requests processed, but is otherwise strictly
1364equivalent to:
1365
1366 IO::AIO::poll_wait, IO::AIO::poll_cb
1367
1368=item IO::AIO::flush
1369
1370Wait till all outstanding AIO requests have been handled.
1371
1372Strictly equivalent to:
1373
1374 IO::AIO::poll_wait, IO::AIO::poll_cb
1375 while IO::AIO::nreqs;
1376
1377=back 1490=back
1378 1491
1379=head3 CONTROLLING THE NUMBER OF THREADS 1492=head3 CONTROLLING THE NUMBER OF THREADS
1380 1493
1381=over 1494=over
… …
1414 1527
1415Under normal circumstances you don't need to call this function. 1528Under normal circumstances you don't need to call this function.
1416 1529
1417=item IO::AIO::max_idle $nthreads 1530=item IO::AIO::max_idle $nthreads
1418 1531
1419Limit the number of threads (default: 4) that are allowed to idle (i.e., 1532Limit the number of threads (default: 4) that are allowed to idle
1420threads that did not get a request to process within 10 seconds). That 1533(i.e., threads that did not get a request to process within the idle
1421means if a thread becomes idle while C<$nthreads> other threads are also 1534timeout (default: 10 seconds). That means if a thread becomes idle while
1422idle, it will free its resources and exit. 1535C<$nthreads> other threads are also idle, it will free its resources and
1536exit.
1423 1537
1424This is useful when you allow a large number of threads (e.g. 100 or 1000) 1538This is useful when you allow a large number of threads (e.g. 100 or 1000)
1425to allow for extremely high load situations, but want to free resources 1539to allow for extremely high load situations, but want to free resources
1426under normal circumstances (1000 threads can easily consume 30MB of RAM). 1540under normal circumstances (1000 threads can easily consume 30MB of RAM).
1427 1541
1428The default is probably ok in most situations, especially if thread 1542The default is probably ok in most situations, especially if thread
1429creation is fast. If thread creation is very slow on your system you might 1543creation is fast. If thread creation is very slow on your system you might
1430want to use larger values. 1544want to use larger values.
1545
1546=item IO::AIO::idle_timeout $seconds
1547
1548Sets the minimum idle timeout (default 10) after which worker threads are
1549allowed to exit. SEe C<IO::AIO::max_idle>.
1431 1550
1432=item IO::AIO::max_outstanding $maxreqs 1551=item IO::AIO::max_outstanding $maxreqs
1433 1552
1434This is a very bad function to use in interactive programs because it 1553This is a very bad function to use in interactive programs because it
1435blocks, and a bad way to reduce concurrency because it is inexact: Better 1554blocks, and a bad way to reduce concurrency because it is inexact: Better
… …
1491 1610
1492Returns the number of bytes copied, or C<-1> on error. 1611Returns the number of bytes copied, or C<-1> on error.
1493 1612
1494=item IO::AIO::fadvise $fh, $offset, $len, $advice 1613=item IO::AIO::fadvise $fh, $offset, $len, $advice
1495 1614
1496Simply calls the C<posix_fadvise> function (see it's 1615Simply calls the C<posix_fadvise> function (see its
1497manpage for details). The following advice constants are 1616manpage for details). The following advice constants are
1498avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, 1617avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1499C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, 1618C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1500C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. 1619C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1501 1620
1502On systems that do not implement C<posix_fadvise>, this function returns 1621On systems that do not implement C<posix_fadvise>, this function returns
1503ENOSYS, otherwise the return value of C<posix_fadvise>. 1622ENOSYS, otherwise the return value of C<posix_fadvise>.
1504 1623
1624=item IO::AIO::madvise $scalar, $offset, $len, $advice
1625
1626Simply calls the C<posix_madvise> function (see its
1627manpage for details). The following advice constants are
1628avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1629C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1630
1631On systems that do not implement C<posix_madvise>, this function returns
1632ENOSYS, otherwise the return value of C<posix_madvise>.
1633
1634=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1635
1636Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1637$scalar (see its manpage for details). The following protect
1638constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1639C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1640
1641On systems that do not implement C<mprotect>, this function returns
1642ENOSYS, otherwise the return value of C<mprotect>.
1643
1644=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1645
1646Memory-maps a file (or anonymous memory range) and attaches it to the
1647given C<$scalar>, which will act like a string scalar.
1648
1649The only operations allowed on the scalar are C<substr>/C<vec> that don't
1650change the string length, and most read-only operations such as copying it
1651or searching it with regexes and so on.
1652
1653Anything else is unsafe and will, at best, result in memory leaks.
1654
1655The memory map associated with the C<$scalar> is automatically removed
1656when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
1657C<IO::AIO::munmap> functions are called.
1658
1659This calls the C<mmap>(2) function internally. See your system's manual
1660page for details on the C<$length>, C<$prot> and C<$flags> parameters.
1661
1662The C<$length> must be larger than zero and smaller than the actual
1663filesize.
1664
1665C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1666C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1667
1668C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
1669C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
1670not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
1671(which is set to C<MAP_ANON> if your system only provides this
1672constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
1673C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
1674C<IO::AIO::MAP_NONBLOCK>
1675
1676If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1677
1678C<$offset> is the offset from the start of the file - it generally must be
1679a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
1680
1681Example:
1682
1683 use Digest::MD5;
1684 use IO::AIO;
1685
1686 open my $fh, "<verybigfile"
1687 or die "$!";
1688
1689 IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
1690 or die "verybigfile: $!";
1691
1692 my $fast_md5 = md5 $data;
1693
1694=item IO::AIO::munmap $scalar
1695
1696Removes a previous mmap and undefines the C<$scalar>.
1697
1698=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
1699
1700Calls the C<munlock> function, undoing the effects of a previous
1701C<aio_mlock> call (see its description for details).
1702
1703=item IO::AIO::munlockall
1704
1705Calls the C<munlockall> function.
1706
1707On systems that do not implement C<munlockall>, this function returns
1708ENOSYS, otherwise the return value of C<munlockall>.
1709
1505=back 1710=back
1506 1711
1507=cut 1712=cut
1508 1713
1509min_parallel 8; 1714min_parallel 8;
1510 1715
1511END { flush } 1716END { flush }
1512 1717
15131; 17181;
1719
1720=head1 EVENT LOOP INTEGRATION
1721
1722It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
1723automatically into many event loops:
1724
1725 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
1726 use AnyEvent::AIO;
1727
1728You can also integrate IO::AIO manually into many event loops, here are
1729some examples of how to do this:
1730
1731 # EV integration
1732 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
1733
1734 # Event integration
1735 Event->io (fd => IO::AIO::poll_fileno,
1736 poll => 'r',
1737 cb => \&IO::AIO::poll_cb);
1738
1739 # Glib/Gtk2 integration
1740 add_watch Glib::IO IO::AIO::poll_fileno,
1741 in => sub { IO::AIO::poll_cb; 1 };
1742
1743 # Tk integration
1744 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
1745 readable => \&IO::AIO::poll_cb);
1746
1747 # Danga::Socket integration
1748 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
1749 \&IO::AIO::poll_cb);
1514 1750
1515=head2 FORK BEHAVIOUR 1751=head2 FORK BEHAVIOUR
1516 1752
1517This module should do "the right thing" when the process using it forks: 1753This module should do "the right thing" when the process using it forks:
1518 1754

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines