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Revision 1.42 by root, Thu Jan 7 20:25:57 2010 UTC vs.
Revision 1.43 by root, Sun Jan 10 23:44:02 2010 UTC

23 my $req = aio_unlink "/tmp/file", sub { }; 23 my $req = aio_unlink "/tmp/file", sub { };
24 $req->cancel; # cancel request if still in queue 24 $req->cancel; # cancel request if still in queue
25 25
26 my $grp = aio_group sub { print "all stats done\n" }; 26 my $grp = aio_group sub { print "all stats done\n" };
27 add $grp aio_stat "..." for ...; 27 add $grp aio_stat "..." for ...;
28
29 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
30 use AnyEvent::AIO;
31
32 # EV integration
33 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
34
35 # Event integration
36 Event->io (fd => IO::AIO::poll_fileno,
37 poll => 'r',
38 cb => \&IO::AIO::poll_cb);
39
40 # Glib/Gtk2 integration
41 add_watch Glib::IO IO::AIO::poll_fileno,
42 in => sub { IO::AIO::poll_cb; 1 };
43
44 # Tk integration
45 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
46 readable => \&IO::AIO::poll_cb);
47
48 # Danga::Socket integration
49 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
50 \&IO::AIO::poll_cb);
51 28
52DESCRIPTION 29DESCRIPTION
53 This module implements asynchronous I/O using whatever means your 30 This module implements asynchronous I/O using whatever means your
54 operating system supports. It is implemented as an interface to "libeio" 31 operating system supports. It is implemented as an interface to "libeio"
55 (<http://software.schmorp.de/pkg/libeio.html>). 32 (<http://software.schmorp.de/pkg/libeio.html>).
168 anymore (except possibly for the Perl object, but its connection to 145 anymore (except possibly for the Perl object, but its connection to
169 the actual aio request is severed and calling its methods will 146 the actual aio request is severed and calling its methods will
170 either do nothing or result in a runtime error). 147 either do nothing or result in a runtime error).
171 148
172FUNCTIONS 149FUNCTIONS
150 QUICK OVERVIEW
151 This section simply lists the prototypes of the most important functions
152 for quick reference. See the following sections for function-by-function
153 documentation.
154
155 aio_open $pathname, $flags, $mode, $callback->($fh)
156 aio_close $fh, $callback->($status)
157 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
158 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
159 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
160 aio_readahead $fh,$offset,$length, $callback->($retval)
161 aio_stat $fh_or_path, $callback->($status)
162 aio_lstat $fh, $callback->($status)
163 aio_statvfs $fh_or_path, $callback->($statvfs)
164 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
165 aio_chown $fh_or_path, $uid, $gid, $callback->($status)
166 aio_truncate $fh_or_path, $offset, $callback->($status)
167 aio_chmod $fh_or_path, $mode, $callback->($status)
168 aio_unlink $pathname, $callback->($status)
169 aio_mknod $path, $mode, $dev, $callback->($status)
170 aio_link $srcpath, $dstpath, $callback->($status)
171 aio_symlink $srcpath, $dstpath, $callback->($status)
172 aio_readlink $path, $callback->($link)
173 aio_rename $srcpath, $dstpath, $callback->($status)
174 aio_mkdir $pathname, $mode, $callback->($status)
175 aio_rmdir $pathname, $callback->($status)
176 aio_readdir $pathname, $callback->($entries)
177 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
178 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
179 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
180 aio_load $path, $data, $callback->($status)
181 aio_copy $srcpath, $dstpath, $callback->($status)
182 aio_move $srcpath, $dstpath, $callback->($status)
183 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
184 aio_rmtree $path, $callback->($status)
185 aio_sync $callback->($status)
186 aio_fsync $fh, $callback->($status)
187 aio_fdatasync $fh, $callback->($status)
188 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
189 aio_pathsync $path, $callback->($status)
190 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
191 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
192 aio_group $callback->(...)
193 aio_nop $callback->()
194
195 $prev_pri = aioreq_pri [$pri]
196 aioreq_nice $pri_adjust
197
198 IO::AIO::poll_wait
199 IO::AIO::poll_cb
200 IO::AIO::poll
201 IO::AIO::flush
202 IO::AIO::max_poll_reqs $nreqs
203 IO::AIO::max_poll_time $seconds
204 IO::AIO::min_parallel $nthreads
205 IO::AIO::max_parallel $nthreads
206 IO::AIO::max_idle $nthreads
207 IO::AIO::max_outstanding $maxreqs
208 IO::AIO::nreqs
209 IO::AIO::nready
210 IO::AIO::npending
211
212 IO::AIO::sendfile $ofh, $ifh, $offset, $count
213 IO::AIO::fadvise $fh, $offset, $len, $advice
214 IO::AIO::mlockall $flags
215 IO::AIO::munlockall
216
173 AIO REQUEST FUNCTIONS 217 AIO REQUEST FUNCTIONS
174 All the "aio_*" calls are more or less thin wrappers around the syscall 218 All the "aio_*" calls are more or less thin wrappers around the syscall
175 with the same name (sans "aio_"). The arguments are similar or 219 with the same name (sans "aio_"). The arguments are similar or
176 identical, and they all accept an additional (and optional) $callback 220 identical, and they all accept an additional (and optional) $callback
177 argument which must be a code reference. This code reference will get 221 argument which must be a code reference. This code reference will get
313 more than one "aio_sendfile" per $out_fh, as they will interfere 357 more than one "aio_sendfile" per $out_fh, as they will interfere
314 with each other. 358 with each other.
315 359
316 This call tries to make use of a native "sendfile" syscall to 360 This call tries to make use of a native "sendfile" syscall to
317 provide zero-copy operation. For this to work, $out_fh should refer 361 provide zero-copy operation. For this to work, $out_fh should refer
318 to a socket, and $in_fh should refer to mmap'able file. 362 to a socket, and $in_fh should refer to an mmap'able file.
319 363
320 If a native sendfile cannot be found or it fails with "ENOSYS", 364 If a native sendfile cannot be found or it fails with "ENOSYS",
321 "ENOTSUP", "EOPNOTSUPP", "EAFNOSUPPORT", "EPROTOTYPE" or "ENOTSOCK", 365 "ENOTSUP", "EOPNOTSUPP", "EAFNOSUPPORT", "EPROTOTYPE" or "ENOTSOCK",
322 it will be emulated, so you can call "aio_sendfile" on any type of 366 it will be emulated, so you can call "aio_sendfile" on any type of
323 filehandle regardless of the limitations of the operating system. 367 filehandle regardless of the limitations of the operating system.
683 Passes 0 when everything went ok, and -1 on error. 727 Passes 0 when everything went ok, and -1 on error.
684 728
685 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, 729 aio_msync $scalar, $offset = 0, $length = undef, flags = 0,
686 $callback->($status) 730 $callback->($status)
687 This is a rather advanced IO::AIO call, which only works on 731 This is a rather advanced IO::AIO call, which only works on
688 mmap(2)ed scalars (see the Sys::Mmap or Mmap modules for details on 732 mmap(2)ed scalars (see the "IO::AIO::mmap" function, although it
733 also works on data scalars managed by the Sys::Mmap or Mmap modules,
689 this, note that the scalar must only be modified in-place while an 734 note that the scalar must only be modified in-place while an aio
690 aio operation is pending on it). 735 operation is pending on it).
691 736
692 It calls the "msync" function of your OS, if available, with the 737 It calls the "msync" function of your OS, if available, with the
693 memory area starting at $offset in the string and ending $length 738 memory area starting at $offset in the string and ending $length
694 bytes later. If $length is negative, counts from the end, and if 739 bytes later. If $length is negative, counts from the end, and if
695 $length is "undef", then it goes till the end of the string. The 740 $length is "undef", then it goes till the end of the string. The
928 973
929 Event->io (fd => IO::AIO::poll_fileno, 974 Event->io (fd => IO::AIO::poll_fileno,
930 poll => 'r', async => 1, 975 poll => 'r', async => 1,
931 cb => \&IO::AIO::poll_cb); 976 cb => \&IO::AIO::poll_cb);
932 977
978 IO::AIO::poll_wait
979 If there are any outstanding requests and none of them in the result
980 phase, wait till the result filehandle becomes ready for reading
981 (simply does a "select" on the filehandle. This is useful if you
982 want to synchronously wait for some requests to finish).
983
984 See "nreqs" for an example.
985
986 IO::AIO::poll
987 Waits until some requests have been handled.
988
989 Returns the number of requests processed, but is otherwise strictly
990 equivalent to:
991
992 IO::AIO::poll_wait, IO::AIO::poll_cb
993
994 IO::AIO::flush
995 Wait till all outstanding AIO requests have been handled.
996
997 Strictly equivalent to:
998
999 IO::AIO::poll_wait, IO::AIO::poll_cb
1000 while IO::AIO::nreqs;
1001
933 IO::AIO::max_poll_reqs $nreqs 1002 IO::AIO::max_poll_reqs $nreqs
934 IO::AIO::max_poll_time $seconds 1003 IO::AIO::max_poll_time $seconds
935 These set the maximum number of requests (default 0, meaning 1004 These set the maximum number of requests (default 0, meaning
936 infinity) that are being processed by "IO::AIO::poll_cb" in one 1005 infinity) that are being processed by "IO::AIO::poll_cb" in one
937 call, respectively the maximum amount of time (default 0, meaning 1006 call, respectively the maximum amount of time (default 0, meaning
960 # use a low priority so other tasks have priority 1029 # use a low priority so other tasks have priority
961 Event->io (fd => IO::AIO::poll_fileno, 1030 Event->io (fd => IO::AIO::poll_fileno,
962 poll => 'r', nice => 1, 1031 poll => 'r', nice => 1,
963 cb => &IO::AIO::poll_cb); 1032 cb => &IO::AIO::poll_cb);
964 1033
965 IO::AIO::poll_wait
966 If there are any outstanding requests and none of them in the result
967 phase, wait till the result filehandle becomes ready for reading
968 (simply does a "select" on the filehandle. This is useful if you
969 want to synchronously wait for some requests to finish).
970
971 See "nreqs" for an example.
972
973 IO::AIO::poll
974 Waits until some requests have been handled.
975
976 Returns the number of requests processed, but is otherwise strictly
977 equivalent to:
978
979 IO::AIO::poll_wait, IO::AIO::poll_cb
980
981 IO::AIO::flush
982 Wait till all outstanding AIO requests have been handled.
983
984 Strictly equivalent to:
985
986 IO::AIO::poll_wait, IO::AIO::poll_cb
987 while IO::AIO::nreqs;
988
989 CONTROLLING THE NUMBER OF THREADS 1034 CONTROLLING THE NUMBER OF THREADS
990 IO::AIO::min_parallel $nthreads 1035 IO::AIO::min_parallel $nthreads
991 Set the minimum number of AIO threads to $nthreads. The current 1036 Set the minimum number of AIO threads to $nthreads. The current
992 default is 8, which means eight asynchronous operations can execute 1037 default is 8, which means eight asynchronous operations can execute
993 concurrently at any one time (the number of outstanding requests, 1038 concurrently at any one time (the number of outstanding requests,
1093 "IO::AIO::FADV_RANDOM", "IO::AIO::FADV_NOREUSE", 1138 "IO::AIO::FADV_RANDOM", "IO::AIO::FADV_NOREUSE",
1094 "IO::AIO::FADV_WILLNEED", "IO::AIO::FADV_DONTNEED". 1139 "IO::AIO::FADV_WILLNEED", "IO::AIO::FADV_DONTNEED".
1095 1140
1096 On systems that do not implement "posix_fadvise", this function 1141 On systems that do not implement "posix_fadvise", this function
1097 returns ENOSYS, otherwise the return value of "posix_fadvise". 1142 returns ENOSYS, otherwise the return value of "posix_fadvise".
1143
1144 IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1145 Memory-maps a file (or anonymous memory range) and attaches it to
1146 the given $scalar, which will act like a string scalar.
1147
1148 The only operations allowed on the scalar are "substr"/"vec" that
1149 don't change the string length, and most read-only operations such
1150 as copying it or searching it with regexes and so on.
1151
1152 Anything else is unsafe and will, at best, result in memory leaks.
1153
1154 The memory map associated with the $scalar is automatically removed
1155 when the $scalar is destroyed, or when the "IO::AIO::mmap" or
1156 "IO::AIO::munmap" functions are called.
1157
1158 This calls the "mmap"(2) function internally. See your system's
1159 manual page for details on the $length, $prot and $flags parameters.
1160
1161 The $length must be larger than zero and smaller than the actual
1162 filesize.
1163
1164 $prot is a combination of "IO::AIO::PROT_NONE",
1165 "IO::AIO::PROT_EXEC", "IO::AIO::PROT_READ" and/or
1166 "IO::AIO::PROT_WRITE",
1167
1168 $flags can be a combination of "IO::AIO::MAP_SHARED" or
1169 "IO::AIO::MAP_PRIVATE", or a number of system-specific flags (when
1170 not available, the are defined as 0): "IO::AIO::MAP_ANONYMOUS"
1171 (which is set to "MAP_ANON" if your system only provides this
1172 constant), "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_LOCKED",
1173 "IO::AIO::MAP_NORESERVE", "IO::AIO::MAP_POPULATE" or
1174 "IO::AIO::MAP_NONBLOCK"
1175
1176 If $fh is "undef", then a file descriptor of -1 is passed.
1177
1178 $offset is the offset from the start of the file - it generally must
1179 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0.
1180
1181 Example:
1182
1183 use Digest::MD5;
1184 use IO::AIO;
1185
1186 open my $fh, "<verybigfile"
1187 or die "$!";
1188
1189 IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
1190 or die "verybigfile: $!";
1191
1192 my $fast_md5 = md5 $data;
1193
1194 IO::AIO::munmap $scalar
1195 Removes a previous mmap and undefines the $scalar.
1196
1197 IO::AIO::mlockall $flags
1198 Calls the "mlockall" function with the given $flags (a combination
1199 of "IO::AIO::MCL_CURRENT" and "IO::AIO::MCL__FUTURE").
1200
1201 On systems that do not implement "mlockall", this function returns
1202 ENOSYS, otherwise the return value of "mlockall".
1203
1204 IO::AIO::munlockall
1205 Calls the "munlockall" function.
1206
1207 On systems that do not implement "munlockall", this function returns
1208 ENOSYS, otherwise the return value of "munlockall".
1209
1210EVENT LOOP INTEGRATION
1211 It is recommended to use AnyEvent::AIO to integrate IO::AIO
1212 automatically into many event loops:
1213
1214 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
1215 use AnyEvent::AIO;
1216
1217 You can also integrate IO::AIO manually into many event loops, here are
1218 some examples of how to do this:
1219
1220 # EV integration
1221 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
1222
1223 # Event integration
1224 Event->io (fd => IO::AIO::poll_fileno,
1225 poll => 'r',
1226 cb => \&IO::AIO::poll_cb);
1227
1228 # Glib/Gtk2 integration
1229 add_watch Glib::IO IO::AIO::poll_fileno,
1230 in => sub { IO::AIO::poll_cb; 1 };
1231
1232 # Tk integration
1233 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
1234 readable => \&IO::AIO::poll_cb);
1235
1236 # Danga::Socket integration
1237 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
1238 \&IO::AIO::poll_cb);
1098 1239
1099 FORK BEHAVIOUR 1240 FORK BEHAVIOUR
1100 This module should do "the right thing" when the process using it forks: 1241 This module should do "the right thing" when the process using it forks:
1101 1242
1102 Before the fork, IO::AIO enters a quiescent state where no requests can 1243 Before the fork, IO::AIO enters a quiescent state where no requests can

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