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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.131 by root, Tue Jul 15 10:42:26 2008 UTC vs.
Revision 1.148 by root, Sat Jun 6 17:25:13 2009 UTC

193use strict 'vars'; 193use strict 'vars';
194 194
195use base 'Exporter'; 195use base 'Exporter';
196 196
197BEGIN { 197BEGIN {
198 our $VERSION = '3.06'; 198 our $VERSION = '3.19';
199 199
200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 200 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir 201 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync 202 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
203 aio_fdatasync aio_pathsync aio_readahead 203 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
204 aio_rename aio_link aio_move aio_copy aio_group 204 aio_rename aio_link aio_move aio_copy aio_group
205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 205 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
206 aio_chmod aio_utime aio_truncate); 206 aio_chmod aio_utime aio_truncate);
207 207
208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 208 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
209 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 209 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
210 min_parallel max_parallel max_idle 210 min_parallel max_parallel max_idle
211 nreqs nready npending nthreads 211 nreqs nready npending nthreads
212 max_poll_time max_poll_reqs); 212 max_poll_time max_poll_reqs);
213 213
214 push @AIO_REQ, qw(aio_busy); # not exported
215
214 @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; 216 @IO::AIO::GRP::ISA = 'IO::AIO::REQ';
215 217
216 require XSLoader; 218 require XSLoader;
217 XSLoader::load ("IO::AIO", $VERSION); 219 XSLoader::load ("IO::AIO", $VERSION);
218} 220}
224All the C<aio_*> calls are more or less thin wrappers around the syscall 226All the C<aio_*> calls are more or less thin wrappers around the syscall
225with the same name (sans C<aio_>). The arguments are similar or identical, 227with the same name (sans C<aio_>). The arguments are similar or identical,
226and they all accept an additional (and optional) C<$callback> argument 228and they all accept an additional (and optional) C<$callback> argument
227which must be a code reference. This code reference will get called with 229which must be a code reference. This code reference will get called with
228the syscall return code (e.g. most syscalls return C<-1> on error, unlike 230the syscall return code (e.g. most syscalls return C<-1> on error, unlike
229perl, which usually delivers "false") as it's sole argument when the given 231perl, which usually delivers "false") as its sole argument after the given
230syscall has been executed asynchronously. 232syscall has been executed asynchronously.
231 233
232All functions expecting a filehandle keep a copy of the filehandle 234All functions expecting a filehandle keep a copy of the filehandle
233internally until the request has finished. 235internally until the request has finished.
234 236
248your pathnames to the locale (or other) encoding in effect in the user 250your pathnames to the locale (or other) encoding in effect in the user
249environment, d) use Glib::filename_from_unicode on unicode filenames or e) 251environment, d) use Glib::filename_from_unicode on unicode filenames or e)
250use something else to ensure your scalar has the correct contents. 252use something else to ensure your scalar has the correct contents.
251 253
252This works, btw. independent of the internal UTF-8 bit, which IO::AIO 254This works, btw. independent of the internal UTF-8 bit, which IO::AIO
253handles correctly wether it is set or not. 255handles correctly whether it is set or not.
254 256
255=over 4 257=over 4
256 258
257=item $prev_pri = aioreq_pri [$pri] 259=item $prev_pri = aioreq_pri [$pri]
258 260
336 338
337=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 339=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
338 340
339=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 341=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
340 342
341Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset> 343Reads or writes C<$length> bytes from or to the specified C<$fh> and
342into the scalar given by C<$data> and offset C<$dataoffset> and calls the 344C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
343callback without the actual number of bytes read (or -1 on error, just 345and calls the callback without the actual number of bytes read (or -1 on
344like the syscall). 346error, just like the syscall).
347
348C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
349offset plus the actual number of bytes read.
345 350
346If C<$offset> is undefined, then the current file descriptor offset will 351If C<$offset> is undefined, then the current file descriptor offset will
347be used (and updated), otherwise the file descriptor offset will not be 352be used (and updated), otherwise the file descriptor offset will not be
348changed by these calls. 353changed by these calls.
349 354
350If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. 355If C<$length> is undefined in C<aio_write>, use the remaining length of
356C<$data>.
351 357
352If C<$dataoffset> is less than zero, it will be counted from the end of 358If C<$dataoffset> is less than zero, it will be counted from the end of
353C<$data>. 359C<$data>.
354 360
355The C<$data> scalar I<MUST NOT> be modified in any way while the request 361The C<$data> scalar I<MUST NOT> be modified in any way while the request
527 533
528Unlike the POSIX call of the same name, C<aio_readdir> reads an entire 534Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
529directory (i.e. opendir + readdir + closedir). The entries will not be 535directory (i.e. opendir + readdir + closedir). The entries will not be
530sorted, and will B<NOT> include the C<.> and C<..> entries. 536sorted, and will B<NOT> include the C<.> and C<..> entries.
531 537
532The callback a single argument which is either C<undef> or an array-ref 538The callback is passed a single argument which is either C<undef> or an
533with the filenames. 539array-ref with the filenames.
540
541
542=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
543
544Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
545behaviour and output format. In case of an error, C<$entries> will be
546C<undef>.
547
548The flags are a combination of the following constants, ORed together (the
549flags will also be passed to the callback, possibly modified):
550
551=over 4
552
553=item AIO::READDIR_DENTS
554
555When this flag is off, then the callback gets an arrayref with of names
556only (as with C<aio_readdir>), otherwise it gets an arrayref with
557C<[$name, $inode, $type]> arrayrefs, each describing a single directory
558entry in more detail.
559
560C<$name> is the name of the entry.
561
562C<$inode> is the inode number (which might not be exact on systems with 64
563bit inode numbers and 32 bit perls). On systems that do not deliver the
564inode information, this will always be zero.
565
566C<$type> is one of the C<AIO::DT_xxx> constants:
567
568C<AIO::DT_UNKNOWN>, C<AIO::DT_FIFO>, C<AIO::DT_CHR>, C<AIO::DT_DIR>,
569C<AIO::DT_BLK>, C<AIO::DT_REG>, C<AIO::DT_LNK>, C<AIO::DT_SOCK>,
570C<AIO::DT_WHT>.
571
572C<AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
573know, you have to run stat yourself. Also, for speed reasons, the C<$type>
574scalars are read-only: you can not modify them.
575
576=item AIO::READDIR_DIRS_FIRST
577
578When this flag is set, then the names will be returned in an order where
579likely directories come first. This is useful when you need to quickly
580find directories, or you want to find all directories while avoiding to
581stat() each entry.
582
583=item AIO::READDIR_STAT_ORDER
584
585When this flag is set, then the names will be returned in an order
586suitable for stat()'ing each one. That is, when you plan to stat()
587all files in the given directory, then the returned order will likely
588be fastest.
589
590If both this flag and IO::READDIR_DIRS_FIRST are specified, then the
591likely dirs come first, resulting in a less optimal stat order.
592
593=item AIO::READDIR_FOUND_UNKNOWN
594
595This flag should not be set when calling C<aio_readdirx>. Instead, it
596is being set by C<aio_readdirx>, when any of the C<$type>'s found were
597C<AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
598C<$type>'s are known, which can be used to speed up some algorithms.
599
600=back
534 601
535 602
536=item aio_load $path, $data, $callback->($status) 603=item aio_load $path, $data, $callback->($status)
537 604
538This is a composite request that tries to fully load the given file into 605This is a composite request that tries to fully load the given file into
565 632
566Try to copy the I<file> (directories not supported as either source or 633Try to copy the I<file> (directories not supported as either source or
567destination) from C<$srcpath> to C<$dstpath> and call the callback with 634destination) from C<$srcpath> to C<$dstpath> and call the callback with
568the C<0> (error) or C<-1> ok. 635the C<0> (error) or C<-1> ok.
569 636
570This is a composite request that it creates the destination file with 637This is a composite request that creates the destination file with
571mode 0200 and copies the contents of the source file into it using 638mode 0200 and copies the contents of the source file into it using
572C<aio_sendfile>, followed by restoring atime, mtime, access mode and 639C<aio_sendfile>, followed by restoring atime, mtime, access mode and
573uid/gid, in that order. 640uid/gid, in that order.
574 641
575If an error occurs, the partial destination file will be unlinked, if 642If an error occurs, the partial destination file will be unlinked, if
585 my $grp = aio_group $cb; 652 my $grp = aio_group $cb;
586 653
587 aioreq_pri $pri; 654 aioreq_pri $pri;
588 add $grp aio_open $src, O_RDONLY, 0, sub { 655 add $grp aio_open $src, O_RDONLY, 0, sub {
589 if (my $src_fh = $_[0]) { 656 if (my $src_fh = $_[0]) {
590 my @stat = stat $src_fh; 657 my @stat = stat $src_fh; # hmm, might bock over nfs?
591 658
592 aioreq_pri $pri; 659 aioreq_pri $pri;
593 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { 660 add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {
594 if (my $dst_fh = $_[0]) { 661 if (my $dst_fh = $_[0]) {
595 aioreq_pri $pri; 662 aioreq_pri $pri;
596 add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { 663 add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
597 if ($_[0] == $stat[7]) { 664 if ($_[0] == $stat[7]) {
598 $grp->result (0); 665 $grp->result (0);
599 close $src_fh; 666 close $src_fh;
600 667
601 # those should not normally block. should. should. 668 my $ch = sub {
602 utime $stat[8], $stat[9], $dst; 669 aioreq_pri $pri;
603 chmod $stat[2] & 07777, $dst_fh; 670 add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
604 chown $stat[4], $stat[5], $dst_fh; 671 aioreq_pri $pri;
672 add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
673 aioreq_pri $pri;
674 add $grp aio_close $dst_fh;
675 }
676 };
677 };
605 678
606 aioreq_pri $pri; 679 aioreq_pri $pri;
607 add $grp aio_close $dst_fh; 680 add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
681 if ($_[0] < 0 && $! == ENOSYS) {
682 aioreq_pri $pri;
683 add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
684 } else {
685 $ch->();
686 }
687 };
608 } else { 688 } else {
609 $grp->result (-1); 689 $grp->result (-1);
610 close $src_fh; 690 close $src_fh;
611 close $dst_fh; 691 close $dst_fh;
612 692
631 711
632Try to move the I<file> (directories not supported as either source or 712Try to move the I<file> (directories not supported as either source or
633destination) from C<$srcpath> to C<$dstpath> and call the callback with 713destination) from C<$srcpath> to C<$dstpath> and call the callback with
634the C<0> (error) or C<-1> ok. 714the C<0> (error) or C<-1> ok.
635 715
636This is a composite request that tries to rename(2) the file first. If 716This is a composite request that tries to rename(2) the file first; if
637rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if 717rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
638that is successful, unlinking the C<$srcpath>. 718that is successful, unlinks the C<$srcpath>.
639 719
640=cut 720=cut
641 721
642sub aio_move($$;$) { 722sub aio_move($$;$) {
643 my ($src, $dst, $cb) = @_; 723 my ($src, $dst, $cb) = @_;
735 my $now = time; 815 my $now = time;
736 my $hash1 = join ":", (stat _)[0,1,3,7,9]; 816 my $hash1 = join ":", (stat _)[0,1,3,7,9];
737 817
738 # read the directory entries 818 # read the directory entries
739 aioreq_pri $pri; 819 aioreq_pri $pri;
740 add $grp aio_readdir $path, sub { 820 add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
741 my $entries = shift 821 my $entries = shift
742 or return $grp->result (); 822 or return $grp->result ();
743 823
744 # stat the dir another time 824 # stat the dir another time
745 aioreq_pri $pri; 825 aioreq_pri $pri;
855callback with the fdatasync result code. 935callback with the fdatasync result code.
856 936
857If this call isn't available because your OS lacks it or it couldn't be 937If this call isn't available because your OS lacks it or it couldn't be
858detected, it will be emulated by calling C<fsync> instead. 938detected, it will be emulated by calling C<fsync> instead.
859 939
940=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
941
942Sync the data portion of the file specified by C<$offset> and C<$length>
943to disk (but NOT the metadata), by calling the Linux-specific
944sync_file_range call. If sync_file_range is not available or it returns
945ENOSYS, then fdatasync or fsync is being substituted.
946
947C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
948C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
949C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
950manpage for details.
951
860=item aio_pathsync $path, $callback->($status) 952=item aio_pathsync $path, $callback->($status)
861 953
862This request tries to open, fsync and close the given path. This is a 954This request tries to open, fsync and close the given path. This is a
863composite request intended tosync directories after directory operations 955composite request intended to sync directories after directory operations
864(E.g. rename). This might not work on all operating systems or have any 956(E.g. rename). This might not work on all operating systems or have any
865specific effect, but usually it makes sure that directory changes get 957specific effect, but usually it makes sure that directory changes get
866written to disc. It works for anything that can be opened for read-only, 958written to disc. It works for anything that can be opened for read-only,
867not just directories. 959not just directories.
868 960
1013Their lifetime, simplified, looks like this: when they are empty, they 1105Their lifetime, simplified, looks like this: when they are empty, they
1014will finish very quickly. If they contain only requests that are in the 1106will finish very quickly. If they contain only requests that are in the
1015C<done> state, they will also finish. Otherwise they will continue to 1107C<done> state, they will also finish. Otherwise they will continue to
1016exist. 1108exist.
1017 1109
1018That means after creating a group you have some time to add requests. And 1110That means after creating a group you have some time to add requests
1019in the callbacks of those requests, you can add further requests to the 1111(precisely before the callback has been invoked, which is only done within
1020group. And only when all those requests have finished will the the group 1112the C<poll_cb>). And in the callbacks of those requests, you can add
1021itself finish. 1113further requests to the group. And only when all those requests have
1114finished will the the group itself finish.
1022 1115
1023=over 4 1116=over 4
1024 1117
1025=item add $grp ... 1118=item add $grp ...
1026 1119
1059=item feed $grp $callback->($grp) 1152=item feed $grp $callback->($grp)
1060 1153
1061Sets a feeder/generator on this group: every group can have an attached 1154Sets a feeder/generator on this group: every group can have an attached
1062generator that generates requests if idle. The idea behind this is that, 1155generator that generates requests if idle. The idea behind this is that,
1063although you could just queue as many requests as you want in a group, 1156although you could just queue as many requests as you want in a group,
1064this might starve other requests for a potentially long time. For 1157this might starve other requests for a potentially long time. For example,
1065example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> 1158C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1066requests, delaying any later requests for a long time. 1159delaying any later requests for a long time.
1067 1160
1068To avoid this, and allow incremental generation of requests, you can 1161To avoid this, and allow incremental generation of requests, you can
1069instead a group and set a feeder on it that generates those requests. The 1162instead a group and set a feeder on it that generates those requests. The
1070feed callback will be called whenever there are few enough (see C<limit>, 1163feed callback will be called whenever there are few enough (see C<limit>,
1071below) requests active in the group itself and is expected to queue more 1164below) requests active in the group itself and is expected to queue more
1075not impose any limits). 1168not impose any limits).
1076 1169
1077If the feed does not queue more requests when called, it will be 1170If the feed does not queue more requests when called, it will be
1078automatically removed from the group. 1171automatically removed from the group.
1079 1172
1080If the feed limit is C<0>, it will be set to C<2> automatically. 1173If the feed limit is C<0> when this method is called, it will be set to
1174C<2> automatically.
1081 1175
1082Example: 1176Example:
1083 1177
1084 # stat all files in @files, but only ever use four aio requests concurrently: 1178 # stat all files in @files, but only ever use four aio requests concurrently:
1085 1179
1096 1190
1097Sets the feeder limit for the group: The feeder will be called whenever 1191Sets the feeder limit for the group: The feeder will be called whenever
1098the group contains less than this many requests. 1192the group contains less than this many requests.
1099 1193
1100Setting the limit to C<0> will pause the feeding process. 1194Setting the limit to C<0> will pause the feeding process.
1195
1196The default value for the limit is C<0>, but note that setting a feeder
1197automatically bumps it up to C<2>.
1101 1198
1102=back 1199=back
1103 1200
1104=head2 SUPPORT FUNCTIONS 1201=head2 SUPPORT FUNCTIONS
1105 1202

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