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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 1.146 by root, Tue Apr 21 20:06:05 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
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<$data> scalar I<MUST NOT> be modified in any way while the request
565 571
566Try to copy the I<file> (directories not supported as either source or 572Try to copy the I<file> (directories not supported as either source or
567destination) from C<$srcpath> to C<$dstpath> and call the callback with 573destination) from C<$srcpath> to C<$dstpath> and call the callback with
568the C<0> (error) or C<-1> ok. 574the C<0> (error) or C<-1> ok.
569 575
570This is a composite request that it creates the destination file with 576This is a composite request that creates the destination file with
571mode 0200 and copies the contents of the source file into it using 577mode 0200 and copies the contents of the source file into it using
572C<aio_sendfile>, followed by restoring atime, mtime, access mode and 578C<aio_sendfile>, followed by restoring atime, mtime, access mode and
573uid/gid, in that order. 579uid/gid, in that order.
574 580
575If an error occurs, the partial destination file will be unlinked, if 581If an error occurs, the partial destination file will be unlinked, if
631 637
632Try to move the I<file> (directories not supported as either source or 638Try to move the I<file> (directories not supported as either source or
633destination) from C<$srcpath> to C<$dstpath> and call the callback with 639destination) from C<$srcpath> to C<$dstpath> and call the callback with
634the C<0> (error) or C<-1> ok. 640the C<0> (error) or C<-1> ok.
635 641
636This is a composite request that tries to rename(2) the file first. If 642This is a composite request that tries to rename(2) the file first; if
637rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if 643rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
638that is successful, unlinking the C<$srcpath>. 644that is successful, unlinks the C<$srcpath>.
639 645
640=cut 646=cut
641 647
642sub aio_move($$;$) { 648sub aio_move($$;$) {
643 my ($src, $dst, $cb) = @_; 649 my ($src, $dst, $cb) = @_;
855callback with the fdatasync result code. 861callback with the fdatasync result code.
856 862
857If this call isn't available because your OS lacks it or it couldn't be 863If 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. 864detected, it will be emulated by calling C<fsync> instead.
859 865
866=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
867
868Sync the data portion of the file specified by C<$offset> and C<$length>
869to disk (but NOT the metadata), by calling the Linux-specific
870sync_file_range call. If sync_file_range is not available or it returns
871ENOSYS, then fdatasync or fsync is being substituted.
872
873C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
874C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
875C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
876manpage for details.
877
860=item aio_pathsync $path, $callback->($status) 878=item aio_pathsync $path, $callback->($status)
861 879
862This request tries to open, fsync and close the given path. This is a 880This request tries to open, fsync and close the given path. This is a
863composite request intended tosync directories after directory operations 881composite request intended to sync directories after directory operations
864(E.g. rename). This might not work on all operating systems or have any 882(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 883specific effect, but usually it makes sure that directory changes get
866written to disc. It works for anything that can be opened for read-only, 884written to disc. It works for anything that can be opened for read-only,
867not just directories. 885not just directories.
868 886
1013Their lifetime, simplified, looks like this: when they are empty, they 1031Their lifetime, simplified, looks like this: when they are empty, they
1014will finish very quickly. If they contain only requests that are in the 1032will finish very quickly. If they contain only requests that are in the
1015C<done> state, they will also finish. Otherwise they will continue to 1033C<done> state, they will also finish. Otherwise they will continue to
1016exist. 1034exist.
1017 1035
1018That means after creating a group you have some time to add requests. And 1036That 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 1037(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 1038the C<poll_cb>). And in the callbacks of those requests, you can add
1021itself finish. 1039further requests to the group. And only when all those requests have
1040finished will the the group itself finish.
1022 1041
1023=over 4 1042=over 4
1024 1043
1025=item add $grp ... 1044=item add $grp ...
1026 1045
1059=item feed $grp $callback->($grp) 1078=item feed $grp $callback->($grp)
1060 1079
1061Sets a feeder/generator on this group: every group can have an attached 1080Sets a feeder/generator on this group: every group can have an attached
1062generator that generates requests if idle. The idea behind this is that, 1081generator 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, 1082although you could just queue as many requests as you want in a group,
1064this might starve other requests for a potentially long time. For 1083this might starve other requests for a potentially long time. For example,
1065example, C<aio_scandir> might generate hundreds of thousands C<aio_stat> 1084C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1066requests, delaying any later requests for a long time. 1085delaying any later requests for a long time.
1067 1086
1068To avoid this, and allow incremental generation of requests, you can 1087To avoid this, and allow incremental generation of requests, you can
1069instead a group and set a feeder on it that generates those requests. The 1088instead 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>, 1089feed 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 1090below) requests active in the group itself and is expected to queue more
1075not impose any limits). 1094not impose any limits).
1076 1095
1077If the feed does not queue more requests when called, it will be 1096If the feed does not queue more requests when called, it will be
1078automatically removed from the group. 1097automatically removed from the group.
1079 1098
1080If the feed limit is C<0>, it will be set to C<2> automatically. 1099If the feed limit is C<0> when this method is called, it will be set to
1100C<2> automatically.
1081 1101
1082Example: 1102Example:
1083 1103
1084 # stat all files in @files, but only ever use four aio requests concurrently: 1104 # stat all files in @files, but only ever use four aio requests concurrently:
1085 1105
1096 1116
1097Sets the feeder limit for the group: The feeder will be called whenever 1117Sets the feeder limit for the group: The feeder will be called whenever
1098the group contains less than this many requests. 1118the group contains less than this many requests.
1099 1119
1100Setting the limit to C<0> will pause the feeding process. 1120Setting the limit to C<0> will pause the feeding process.
1121
1122The default value for the limit is C<0>, but note that setting a feeder
1123automatically bumps it up to C<2>.
1101 1124
1102=back 1125=back
1103 1126
1104=head2 SUPPORT FUNCTIONS 1127=head2 SUPPORT FUNCTIONS
1105 1128

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