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Revision 1.45 by root, Thu Dec 30 07:19:31 2010 UTC vs.
Revision 1.47 by root, Fri May 27 00:44:49 2011 UTC

204 IO::AIO::max_poll_reqs $nreqs 204 IO::AIO::max_poll_reqs $nreqs
205 IO::AIO::max_poll_time $seconds 205 IO::AIO::max_poll_time $seconds
206 IO::AIO::min_parallel $nthreads 206 IO::AIO::min_parallel $nthreads
207 IO::AIO::max_parallel $nthreads 207 IO::AIO::max_parallel $nthreads
208 IO::AIO::max_idle $nthreads 208 IO::AIO::max_idle $nthreads
209 IO::AIO::idle_timeout $seconds
209 IO::AIO::max_outstanding $maxreqs 210 IO::AIO::max_outstanding $maxreqs
210 IO::AIO::nreqs 211 IO::AIO::nreqs
211 IO::AIO::nready 212 IO::AIO::nready
212 IO::AIO::npending 213 IO::AIO::npending
213 214
304 ... 305 ...
305 } else { 306 } else {
306 die "open failed: $!\n"; 307 die "open failed: $!\n";
307 } 308 }
308 }; 309 };
310
311 In addition to all the common open modes/flags ("O_RDONLY",
312 "O_WRONLY", "O_RDWR", "O_CREAT", "O_TRUNC", "O_EXCL" and
313 "O_APPEND"), the following POSIX and non-POSIX constants are
314 available (missing ones on your system are, as usual, 0):
315
316 "O_ASYNC", "O_DIRECT", "O_NOATIME", "O_CLOEXEC", "O_NOCTTY",
317 "O_NOFOLLOW", "O_NONBLOCK", "O_EXEC", "O_SEARCH", "O_DIRECTORY",
318 "O_DSYNC", "O_RSYNC", "O_SYNC" and "O_TTY_INIT".
309 319
310 aio_close $fh, $callback->($status) 320 aio_close $fh, $callback->($status)
311 Asynchronously close a file and call the callback with the result 321 Asynchronously close a file and call the callback with the result
312 code. 322 code.
313 323
413 423
414 Currently, the stats are always 64-bit-stats, i.e. instead of 424 Currently, the stats are always 64-bit-stats, i.e. instead of
415 returning an error when stat'ing a large file, the results will be 425 returning an error when stat'ing a large file, the results will be
416 silently truncated unless perl itself is compiled with large file 426 silently truncated unless perl itself is compiled with large file
417 support. 427 support.
428
429 To help interpret the mode and dev/rdev stat values, IO::AIO offers
430 the following constants and functions (if not implemented, the
431 constants will be 0 and the functions will either "croak" or fall
432 back on traditional behaviour).
433
434 "S_IFMT", "S_IFIFO", "S_IFCHR", "S_IFBLK", "S_IFLNK", "S_IFREG",
435 "S_IFDIR", "S_IFWHT", "S_IFSOCK", "IO::AIO::major $dev_t",
436 "IO::AIO::minor $dev_t", "IO::AIO::makedev $major, $minor".
418 437
419 Example: Print the length of /etc/passwd: 438 Example: Print the length of /etc/passwd:
420 439
421 aio_stat "/etc/passwd", sub { 440 aio_stat "/etc/passwd", sub {
422 $_[0] and die "stat failed: $!"; 441 $_[0] and die "stat failed: $!";
511 530
512 The only (POSIX-) portable way of calling this function is: 531 The only (POSIX-) portable way of calling this function is:
513 532
514 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... 533 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ...
515 534
535 See "aio_stat" for info about some potentially helpful extra
536 constants and functions.
537
516 aio_link $srcpath, $dstpath, $callback->($status) 538 aio_link $srcpath, $dstpath, $callback->($status)
517 Asynchronously create a new link to the existing object at $srcpath 539 Asynchronously create a new link to the existing object at $srcpath
518 at the path $dstpath and call the callback with the result code. 540 at the path $dstpath and call the callback with the result code.
519 541
520 aio_symlink $srcpath, $dstpath, $callback->($status) 542 aio_symlink $srcpath, $dstpath, $callback->($status)
556 The flags are a combination of the following constants, ORed 578 The flags are a combination of the following constants, ORed
557 together (the flags will also be passed to the callback, possibly 579 together (the flags will also be passed to the callback, possibly
558 modified): 580 modified):
559 581
560 IO::AIO::READDIR_DENTS 582 IO::AIO::READDIR_DENTS
561 When this flag is off, then the callback gets an arrayref with 583 When this flag is off, then the callback gets an arrayref
562 of names only (as with "aio_readdir"), otherwise it gets an 584 consisting of names only (as with "aio_readdir"), otherwise it
563 arrayref with "[$name, $type, $inode]" arrayrefs, each 585 gets an arrayref with "[$name, $type, $inode]" arrayrefs, each
564 describing a single directory entry in more detail. 586 describing a single directory entry in more detail.
565 587
566 $name is the name of the entry. 588 $name is the name of the entry.
567 589
568 $type is one of the "IO::AIO::DT_xxx" constants: 590 $type is one of the "IO::AIO::DT_xxx" constants:
581 unspecified content on systems that do not deliver the inode 603 unspecified content on systems that do not deliver the inode
582 information. 604 information.
583 605
584 IO::AIO::READDIR_DIRS_FIRST 606 IO::AIO::READDIR_DIRS_FIRST
585 When this flag is set, then the names will be returned in an 607 When this flag is set, then the names will be returned in an
586 order where likely directories come first. This is useful when 608 order where likely directories come first, in optimal stat
587 you need to quickly find directories, or you want to find all 609 order. This is useful when you need to quickly find directories,
588 directories while avoiding to stat() each entry. 610 or you want to find all directories while avoiding to stat()
611 each entry.
589 612
590 If the system returns type information in readdir, then this is 613 If the system returns type information in readdir, then this is
591 used to find directories directly. Otherwise, likely directories 614 used to find directories directly. Otherwise, likely directories
592 are files beginning with ".", or otherwise files with no dots, 615 are names beginning with ".", or otherwise names with no dots,
593 of which files with short names are tried first. 616 of which names with short names are tried first.
594 617
595 IO::AIO::READDIR_STAT_ORDER 618 IO::AIO::READDIR_STAT_ORDER
596 When this flag is set, then the names will be returned in an 619 When this flag is set, then the names will be returned in an
597 order suitable for stat()'ing each one. That is, when you plan 620 order suitable for stat()'ing each one. That is, when you plan
598 to stat() all files in the given directory, then the returned 621 to stat() all files in the given directory, then the returned
1009 1032
1010 See "poll_cb" for an example. 1033 See "poll_cb" for an example.
1011 1034
1012 IO::AIO::poll_cb 1035 IO::AIO::poll_cb
1013 Process some outstanding events on the result pipe. You have to call 1036 Process some outstanding events on the result pipe. You have to call
1014 this regularly. Returns 0 if all events could be processed, or -1 if 1037 this regularly. Returns 0 if all events could be processed (or there
1015 it returned earlier for whatever reason. Returns immediately when no 1038 were no events to process), or -1 if it returned earlier for
1016 events are outstanding. The amount of events processed depends on 1039 whatever reason. Returns immediately when no events are outstanding.
1017 the settings of "IO::AIO::max_poll_req" and 1040 The amount of events processed depends on the settings of
1018 "IO::AIO::max_poll_time". 1041 "IO::AIO::max_poll_req" and "IO::AIO::max_poll_time".
1019 1042
1020 If not all requests were processed for whatever reason, the 1043 If not all requests were processed for whatever reason, the
1021 filehandle will still be ready when "poll_cb" returns, so normally 1044 filehandle will still be ready when "poll_cb" returns, so normally
1022 you don't have to do anything special to have it called later. 1045 you don't have to do anything special to have it called later.
1046
1047 Apart from calling "IO::AIO::poll_cb" when the event filehandle
1048 becomes ready, it can be beneficial to call this function from loops
1049 which submit a lot of requests, to make sure the results get
1050 processed when they become available and not just when the loop is
1051 finished and the event loop takes over again. This function returns
1052 very fast when there are no outstanding requests.
1023 1053
1024 Example: Install an Event watcher that automatically calls 1054 Example: Install an Event watcher that automatically calls
1025 IO::AIO::poll_cb with high priority (more examples can be found in 1055 IO::AIO::poll_cb with high priority (more examples can be found in
1026 the SYNOPSIS section, at the top of this document): 1056 the SYNOPSIS section, at the top of this document):
1027 1057
1121 1151
1122 Under normal circumstances you don't need to call this function. 1152 Under normal circumstances you don't need to call this function.
1123 1153
1124 IO::AIO::max_idle $nthreads 1154 IO::AIO::max_idle $nthreads
1125 Limit the number of threads (default: 4) that are allowed to idle 1155 Limit the number of threads (default: 4) that are allowed to idle
1126 (i.e., threads that did not get a request to process within 10 1156 (i.e., threads that did not get a request to process within the idle
1127 seconds). That means if a thread becomes idle while $nthreads other 1157 timeout (default: 10 seconds). That means if a thread becomes idle
1128 threads are also idle, it will free its resources and exit. 1158 while $nthreads other threads are also idle, it will free its
1159 resources and exit.
1129 1160
1130 This is useful when you allow a large number of threads (e.g. 100 or 1161 This is useful when you allow a large number of threads (e.g. 100 or
1131 1000) to allow for extremely high load situations, but want to free 1162 1000) to allow for extremely high load situations, but want to free
1132 resources under normal circumstances (1000 threads can easily 1163 resources under normal circumstances (1000 threads can easily
1133 consume 30MB of RAM). 1164 consume 30MB of RAM).
1134 1165
1135 The default is probably ok in most situations, especially if thread 1166 The default is probably ok in most situations, especially if thread
1136 creation is fast. If thread creation is very slow on your system you 1167 creation is fast. If thread creation is very slow on your system you
1137 might want to use larger values. 1168 might want to use larger values.
1169
1170 IO::AIO::idle_timeout $seconds
1171 Sets the minimum idle timeout (default 10) after which worker
1172 threads are allowed to exit. SEe "IO::AIO::max_idle".
1138 1173
1139 IO::AIO::max_outstanding $maxreqs 1174 IO::AIO::max_outstanding $maxreqs
1140 This is a very bad function to use in interactive programs because 1175 This is a very bad function to use in interactive programs because
1141 it blocks, and a bad way to reduce concurrency because it is 1176 it blocks, and a bad way to reduce concurrency because it is
1142 inexact: Better use an "aio_group" together with a feed callback. 1177 inexact: Better use an "aio_group" together with a feed callback.

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