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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.244 by root, Fri Jan 24 23:46:16 2014 UTC vs.
Revision 1.263 by root, Tue Jul 12 20:46:33 2016 UTC

94 94
95 # file contents now in $contents 95 # file contents now in $contents
96 print $contents; 96 print $contents;
97 97
98 # exit event loop and program 98 # exit event loop and program
99 EV::unloop; 99 EV::break;
100 }; 100 };
101 }; 101 };
102 102
103 # possibly queue up other requests, or open GUI windows, 103 # possibly queue up other requests, or open GUI windows,
104 # check for sockets etc. etc. 104 # check for sockets etc. etc.
105 105
106 # process events as long as there are some: 106 # process events as long as there are some:
107 EV::loop; 107 EV::run;
108 108
109=head1 REQUEST ANATOMY AND LIFETIME 109=head1 REQUEST ANATOMY AND LIFETIME
110 110
111Every C<aio_*> function creates a request. which is a C data structure not 111Every C<aio_*> function creates a request. which is a C data structure not
112directly visible to Perl. 112directly visible to Perl.
167use common::sense; 167use common::sense;
168 168
169use base 'Exporter'; 169use base 'Exporter';
170 170
171BEGIN { 171BEGIN {
172 our $VERSION = '4.19'; 172 our $VERSION = 4.34;
173 173
174 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close 174 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
175 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx 175 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
176 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync 176 aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
177 aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate 177 aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
178 aio_pathsync aio_readahead aio_fiemap 178 aio_pathsync aio_readahead aio_fiemap aio_allocate
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_mlock aio_mlockall 182 aio_msync aio_mtouch aio_mlock aio_mlockall
183 aio_statvfs 183 aio_statvfs
227 aio_unlink $pathname, $callback->($status) 227 aio_unlink $pathname, $callback->($status)
228 aio_mknod $pathname, $mode, $dev, $callback->($status) 228 aio_mknod $pathname, $mode, $dev, $callback->($status)
229 aio_link $srcpath, $dstpath, $callback->($status) 229 aio_link $srcpath, $dstpath, $callback->($status)
230 aio_symlink $srcpath, $dstpath, $callback->($status) 230 aio_symlink $srcpath, $dstpath, $callback->($status)
231 aio_readlink $pathname, $callback->($link) 231 aio_readlink $pathname, $callback->($link)
232 aio_realpath $pathname, $callback->($link) 232 aio_realpath $pathname, $callback->($path)
233 aio_rename $srcpath, $dstpath, $callback->($status) 233 aio_rename $srcpath, $dstpath, $callback->($status)
234 aio_mkdir $pathname, $mode, $callback->($status) 234 aio_mkdir $pathname, $mode, $callback->($status)
235 aio_rmdir $pathname, $callback->($status) 235 aio_rmdir $pathname, $callback->($status)
236 aio_readdir $pathname, $callback->($entries) 236 aio_readdir $pathname, $callback->($entries)
237 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 237 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
240 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) 240 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
241 aio_load $pathname, $data, $callback->($status) 241 aio_load $pathname, $data, $callback->($status)
242 aio_copy $srcpath, $dstpath, $callback->($status) 242 aio_copy $srcpath, $dstpath, $callback->($status)
243 aio_move $srcpath, $dstpath, $callback->($status) 243 aio_move $srcpath, $dstpath, $callback->($status)
244 aio_rmtree $pathname, $callback->($status) 244 aio_rmtree $pathname, $callback->($status)
245 aio_fcntl $fh, $cmd, $arg, $callback->($status)
246 aio_ioctl $fh, $request, $buf, $callback->($status)
245 aio_sync $callback->($status) 247 aio_sync $callback->($status)
246 aio_syncfs $fh, $callback->($status) 248 aio_syncfs $fh, $callback->($status)
247 aio_fsync $fh, $callback->($status) 249 aio_fsync $fh, $callback->($status)
248 aio_fdatasync $fh, $callback->($status) 250 aio_fdatasync $fh, $callback->($status)
249 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) 251 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
394following POSIX and non-POSIX constants are available (missing ones on 396following POSIX and non-POSIX constants are available (missing ones on
395your system are, as usual, C<0>): 397your system are, as usual, C<0>):
396 398
397C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, 399C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
398C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, 400C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
399C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>. 401C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
400 402
401 403
402=item aio_close $fh, $callback->($status) 404=item aio_close $fh, $callback->($status)
403 405
404Asynchronously close a file and call the callback with the result 406Asynchronously close a file and call the callback with the result
508As native sendfile syscalls (as practically any non-POSIX interface hacked 510As native sendfile syscalls (as practically any non-POSIX interface hacked
509together in a hurry to improve benchmark numbers) tend to be rather buggy 511together in a hurry to improve benchmark numbers) tend to be rather buggy
510on many systems, this implementation tries to work around some known bugs 512on many systems, this implementation tries to work around some known bugs
511in Linux and FreeBSD kernels (probably others, too), but that might fail, 513in Linux and FreeBSD kernels (probably others, too), but that might fail,
512so you really really should check the return value of C<aio_sendfile> - 514so you really really should check the return value of C<aio_sendfile> -
513fewre bytes than expected might have been transferred. 515fewer bytes than expected might have been transferred.
514 516
515 517
516=item aio_readahead $fh,$offset,$length, $callback->($retval) 518=item aio_readahead $fh,$offset,$length, $callback->($retval)
517 519
518C<aio_readahead> populates the page cache with data from a file so that 520C<aio_readahead> populates the page cache with data from a file so that
522whole pages, so that offset is effectively rounded down to a page boundary 524whole pages, so that offset is effectively rounded down to a page boundary
523and bytes are read up to the next page boundary greater than or equal to 525and bytes are read up to the next page boundary greater than or equal to
524(off-set+length). C<aio_readahead> does not read beyond the end of the 526(off-set+length). C<aio_readahead> does not read beyond the end of the
525file. The current file offset of the file is left unchanged. 527file. The current file offset of the file is left unchanged.
526 528
527If that syscall doesn't exist (likely if your OS isn't Linux) it will be 529If that syscall doesn't exist (likely if your kernel isn't Linux) it will
528emulated by simply reading the data, which would have a similar effect. 530be emulated by simply reading the data, which would have a similar effect.
529 531
530 532
531=item aio_stat $fh_or_path, $callback->($status) 533=item aio_stat $fh_or_path, $callback->($status)
532 534
533=item aio_lstat $fh, $callback->($status) 535=item aio_lstat $fh, $callback->($status)
626 0x00001373 devfs 628 0x00001373 devfs
627 0x00001cd1 devpts 629 0x00001cd1 devpts
628 0x0000f15f ecryptfs 630 0x0000f15f ecryptfs
629 0x00414a53 efs 631 0x00414a53 efs
630 0x0000137d ext 632 0x0000137d ext
631 0x0000ef53 ext2/ext3 633 0x0000ef53 ext2/ext3/ext4
632 0x0000ef51 ext2 634 0x0000ef51 ext2
635 0xf2f52010 f2fs
633 0x00004006 fat 636 0x00004006 fat
634 0x65735546 fuseblk 637 0x65735546 fuseblk
635 0x65735543 fusectl 638 0x65735543 fusectl
636 0x0bad1dea futexfs 639 0x0bad1dea futexfs
637 0x01161970 gfs2 640 0x01161970 gfs2
638 0x47504653 gpfs 641 0x47504653 gpfs
639 0x00004244 hfs 642 0x00004244 hfs
640 0xf995e849 hpfs 643 0xf995e849 hpfs
644 0x00c0ffee hostfs
641 0x958458f6 hugetlbfs 645 0x958458f6 hugetlbfs
642 0x2bad1dea inotifyfs 646 0x2bad1dea inotifyfs
643 0x00009660 isofs 647 0x00009660 isofs
644 0x000072b6 jffs2 648 0x000072b6 jffs2
645 0x3153464a jfs 649 0x3153464a jfs
660 0x00009fa1 openprom 664 0x00009fa1 openprom
661 0x7461636F ocfs2 665 0x7461636F ocfs2
662 0x00009fa0 proc 666 0x00009fa0 proc
663 0x6165676c pstorefs 667 0x6165676c pstorefs
664 0x0000002f qnx4 668 0x0000002f qnx4
669 0x68191122 qnx6
665 0x858458f6 ramfs 670 0x858458f6 ramfs
666 0x52654973 reiserfs 671 0x52654973 reiserfs
667 0x00007275 romfs 672 0x00007275 romfs
668 0x67596969 rpc_pipefs 673 0x67596969 rpc_pipefs
669 0x73636673 securityfs 674 0x73636673 securityfs
722Works like truncate(2) or ftruncate(2). 727Works like truncate(2) or ftruncate(2).
723 728
724 729
725=item aio_allocate $fh, $mode, $offset, $len, $callback->($status) 730=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
726 731
727Allocates or freed disk space according to the C<$mode> argument. See the 732Allocates or frees disk space according to the C<$mode> argument. See the
728linux C<fallocate> docuemntation for details. 733linux C<fallocate> documentation for details.
729 734
730C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> 735C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
731to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | 736space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>,
732IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range. 737to deallocate a file range.
738
739IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
740(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
741your L<fallocate(2)> manpage).
733 742
734The file system block size used by C<fallocate> is presumably the 743The file system block size used by C<fallocate> is presumably the
735C<f_bsize> returned by C<statvfs>. 744C<f_bsize> returned by C<statvfs>.
736 745
737If C<fallocate> isn't available or cannot be emulated (currently no 746If C<fallocate> isn't available or cannot be emulated (currently no
1220 }; 1229 };
1221 1230
1222 $grp 1231 $grp
1223} 1232}
1224 1233
1234=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
1235
1236=item aio_ioctl $fh, $request, $buf, $callback->($status)
1237
1238These work just like the C<fcntl> and C<ioctl> built-in functions, except
1239they execute asynchronously and pass the return value to the callback.
1240
1241Both calls can be used for a lot of things, some of which make more sense
1242to run asynchronously in their own thread, while some others make less
1243sense. For example, calls that block waiting for external events, such
1244as locking, will also lock down an I/O thread while it is waiting, which
1245can deadlock the whole I/O system. At the same time, there might be no
1246alternative to using a thread to wait.
1247
1248So in general, you should only use these calls for things that do
1249(filesystem) I/O, not for things that wait for other events (network,
1250other processes), although if you are careful and know what you are doing,
1251you still can.
1252
1225=item aio_sync $callback->($status) 1253=item aio_sync $callback->($status)
1226 1254
1227Asynchronously call sync and call the callback when finished. 1255Asynchronously call sync and call the callback when finished.
1228 1256
1229=item aio_fsync $fh, $callback->($status) 1257=item aio_fsync $fh, $callback->($status)
1500 aio_stat [$etcdir, "passwd"], sub { 1528 aio_stat [$etcdir, "passwd"], sub {
1501 # yay 1529 # yay
1502 }; 1530 };
1503 }; 1531 };
1504 1532
1505That C<aio_wd> is a request and not a normal function shows that creating 1533The fact that C<aio_wd> is a request and not a normal function shows that
1506an IO::AIO::WD object is itself a potentially blocking operation, which is 1534creating an IO::AIO::WD object is itself a potentially blocking operation,
1507why it is done asynchronously. 1535which is why it is done asynchronously.
1508 1536
1509To stat the directory obtained with C<aio_wd> above, one could write 1537To stat the directory obtained with C<aio_wd> above, one could write
1510either of the following three request calls: 1538either of the following three request calls:
1511 1539
1512 aio_lstat "/etc" , sub { ... # pathname as normal string 1540 aio_lstat "/etc" , sub { ... # pathname as normal string
1555passing C<undef> as working directory component of a pathname fails the 1583passing C<undef> as working directory component of a pathname fails the
1556request with C<ENOENT>, there is often no need for error checking in the 1584request with C<ENOENT>, there is often no need for error checking in the
1557C<aio_wd> callback, as future requests using the value will fail in the 1585C<aio_wd> callback, as future requests using the value will fail in the
1558expected way. 1586expected way.
1559 1587
1560If this call isn't available because your OS lacks it or it couldn't be
1561detected, it will be emulated by calling C<fsync> instead.
1562
1563=item IO::AIO::CWD 1588=item IO::AIO::CWD
1564 1589
1565This is a compiletime constant (object) that represents the process 1590This is a compiletime constant (object) that represents the process
1566current working directory. 1591current working directory.
1567 1592
1934 1959
1935This is a very bad function to use in interactive programs because it 1960This is a very bad function to use in interactive programs because it
1936blocks, and a bad way to reduce concurrency because it is inexact: Better 1961blocks, and a bad way to reduce concurrency because it is inexact: Better
1937use an C<aio_group> together with a feed callback. 1962use an C<aio_group> together with a feed callback.
1938 1963
1939It's main use is in scripts without an event loop - when you want to stat 1964Its main use is in scripts without an event loop - when you want to stat
1940a lot of files, you can write somehting like this: 1965a lot of files, you can write somehting like this:
1941 1966
1942 IO::AIO::max_outstanding 32; 1967 IO::AIO::max_outstanding 32;
1943 1968
1944 for my $path (...) { 1969 for my $path (...) {
1984 2009
1985=back 2010=back
1986 2011
1987=head3 MISCELLANEOUS FUNCTIONS 2012=head3 MISCELLANEOUS FUNCTIONS
1988 2013
1989IO::AIO implements some functions that might be useful, but are not 2014IO::AIO implements some functions that are useful when you want to use
1990asynchronous. 2015some "Advanced I/O" function not available to in Perl, without going the
2016"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2017counterpart.
1991 2018
1992=over 4 2019=over 4
1993 2020
1994=item IO::AIO::sendfile $ofh, $ifh, $offset, $count 2021=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1995 2022
2014=item IO::AIO::madvise $scalar, $offset, $len, $advice 2041=item IO::AIO::madvise $scalar, $offset, $len, $advice
2015 2042
2016Simply calls the C<posix_madvise> function (see its 2043Simply calls the C<posix_madvise> function (see its
2017manpage for details). The following advice constants are 2044manpage for details). The following advice constants are
2018available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, 2045available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
2019C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. 2046C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>,
2047C<IO::AIO::MADV_FREE>.
2020 2048
2021On systems that do not implement C<posix_madvise>, this function returns 2049On systems that do not implement C<posix_madvise>, this function returns
2022ENOSYS, otherwise the return value of C<posix_madvise>. 2050ENOSYS, otherwise the return value of C<posix_madvise>.
2023 2051
2024=item IO::AIO::mprotect $scalar, $offset, $len, $protect 2052=item IO::AIO::mprotect $scalar, $offset, $len, $protect
2054filesize. 2082filesize.
2055 2083
2056C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, 2084C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
2057C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, 2085C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
2058 2086
2059C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or 2087C<$flags> can be a combination of
2060C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when 2088C<IO::AIO::MAP_SHARED> or
2061not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> 2089C<IO::AIO::MAP_PRIVATE>,
2090or a number of system-specific flags (when not available, the are C<0>):
2062(which is set to C<MAP_ANON> if your system only provides this 2091C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
2063constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, 2092C<IO::AIO::MAP_LOCKED>,
2064C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or 2093C<IO::AIO::MAP_NORESERVE>,
2094C<IO::AIO::MAP_POPULATE>,
2065C<IO::AIO::MAP_NONBLOCK> 2095C<IO::AIO::MAP_NONBLOCK>,
2096C<IO::AIO::MAP_FIXED>,
2097C<IO::AIO::MAP_GROWSDOWN>,
2098C<IO::AIO::MAP_32BIT>,
2099C<IO::AIO::MAP_HUGETLB> or
2100C<IO::AIO::MAP_STACK>.
2066 2101
2067If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. 2102If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
2068 2103
2069C<$offset> is the offset from the start of the file - it generally must be 2104C<$offset> is the offset from the start of the file - it generally must be
2070a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. 2105a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
2113 2148
2114See the C<splice(2)> manpage for details. 2149See the C<splice(2)> manpage for details.
2115 2150
2116=item IO::AIO::tee $r_fh, $w_fh, $length, $flags 2151=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2117 2152
2118Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the 2153Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2119description for C<IO::AIO::splice> above for details. 2154description for C<IO::AIO::splice> above for details.
2120 2155
2121=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] 2156=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
2122 2157
2123Attempts to query or change the pipe buffer size. Obviously works only 2158Attempts to query or change the pipe buffer size. Obviously works only
2124on pipes, and currently works only on GNU/Linux systems, and fails with 2159on pipes, and currently works only on GNU/Linux systems, and fails with
2125C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer 2160C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
2126size on other systems, drop me a note. 2161size on other systems, drop me a note.
2162
2163=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
2164
2165This is a direct interface to the Linux L<pipe2(2)> system call. If
2166C<$flags> is missing or C<0>, then this should be the same as a call to
2167perl's built-in C<pipe> function and create a new pipe, and works on
2168systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
2169(..., 4096, O_BINARY)>.
2170
2171If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
2172the given flags (Linux 2.6.27, glibc 2.9).
2173
2174On success, the read and write file handles are returned.
2175
2176On error, nothing will be returned. If the pipe2 syscall is missing and
2177C<$flags> is non-zero, fails with C<ENOSYS>.
2178
2179Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
2180time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
2181C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2127 2182
2128=back 2183=back
2129 2184
2130=cut 2185=cut
2131 2186

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