… | |
… | |
30 | |
30 | |
31 | # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...) |
31 | # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...) |
32 | use AnyEvent::AIO; |
32 | use AnyEvent::AIO; |
33 | |
33 | |
34 | # EV integration |
34 | # EV integration |
35 | my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
35 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
36 | |
36 | |
37 | # Event integration |
37 | # Event integration |
38 | Event->io (fd => IO::AIO::poll_fileno, |
38 | Event->io (fd => IO::AIO::poll_fileno, |
39 | poll => 'r', |
39 | poll => 'r', |
40 | cb => \&IO::AIO::poll_cb); |
40 | cb => \&IO::AIO::poll_cb); |
… | |
… | |
52 | \&IO::AIO::poll_cb); |
52 | \&IO::AIO::poll_cb); |
53 | |
53 | |
54 | =head1 DESCRIPTION |
54 | =head1 DESCRIPTION |
55 | |
55 | |
56 | This module implements asynchronous I/O using whatever means your |
56 | This module implements asynchronous I/O using whatever means your |
57 | operating system supports. |
57 | operating system supports. It is implemented as an interface to C<libeio> |
|
|
58 | (L<http://software.schmorp.de/pkg/libeio.html>). |
58 | |
59 | |
59 | Asynchronous means that operations that can normally block your program |
60 | Asynchronous means that operations that can normally block your program |
60 | (e.g. reading from disk) will be done asynchronously: the operation |
61 | (e.g. reading from disk) will be done asynchronously: the operation |
61 | will still block, but you can do something else in the meantime. This |
62 | will still block, but you can do something else in the meantime. This |
62 | is extremely useful for programs that need to stay interactive even |
63 | is extremely useful for programs that need to stay interactive even |
… | |
… | |
66 | on a RAID volume or over NFS when you do a number of stat operations |
67 | on a RAID volume or over NFS when you do a number of stat operations |
67 | concurrently. |
68 | concurrently. |
68 | |
69 | |
69 | While most of this works on all types of file descriptors (for |
70 | While most of this works on all types of file descriptors (for |
70 | example sockets), using these functions on file descriptors that |
71 | example sockets), using these functions on file descriptors that |
71 | support nonblocking operation (again, sockets, pipes etc.) is very |
72 | support nonblocking operation (again, sockets, pipes etc.) is |
72 | inefficient. Use an event loop for that (such as the L<Event|Event> |
73 | very inefficient. Use an event loop for that (such as the L<EV> |
73 | module): IO::AIO will naturally fit into such an event loop itself. |
74 | module): IO::AIO will naturally fit into such an event loop itself. |
74 | |
75 | |
75 | In this version, a number of threads are started that execute your |
76 | In this version, a number of threads are started that execute your |
76 | requests and signal their completion. You don't need thread support |
77 | requests and signal their completion. You don't need thread support |
77 | in perl, and the threads created by this module will not be visible |
78 | in perl, and the threads created by this module will not be visible |
… | |
… | |
87 | yourself, always call C<poll_cb> from within the same thread, or never |
88 | yourself, always call C<poll_cb> from within the same thread, or never |
88 | call C<poll_cb> (or other C<aio_> functions) recursively. |
89 | call C<poll_cb> (or other C<aio_> functions) recursively. |
89 | |
90 | |
90 | =head2 EXAMPLE |
91 | =head2 EXAMPLE |
91 | |
92 | |
92 | This is a simple example that uses the Event module and loads |
93 | This is a simple example that uses the EV module and loads |
93 | F</etc/passwd> asynchronously: |
94 | F</etc/passwd> asynchronously: |
94 | |
95 | |
95 | use Fcntl; |
96 | use Fcntl; |
96 | use Event; |
97 | use EV; |
97 | use IO::AIO; |
98 | use IO::AIO; |
98 | |
99 | |
99 | # register the IO::AIO callback with Event |
100 | # register the IO::AIO callback with EV |
100 | Event->io (fd => IO::AIO::poll_fileno, |
101 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
101 | poll => 'r', |
|
|
102 | cb => \&IO::AIO::poll_cb); |
|
|
103 | |
102 | |
104 | # queue the request to open /etc/passwd |
103 | # queue the request to open /etc/passwd |
105 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
104 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
106 | my $fh = shift |
105 | my $fh = shift |
107 | or die "error while opening: $!"; |
106 | or die "error while opening: $!"; |
… | |
… | |
119 | |
118 | |
120 | # file contents now in $contents |
119 | # file contents now in $contents |
121 | print $contents; |
120 | print $contents; |
122 | |
121 | |
123 | # exit event loop and program |
122 | # exit event loop and program |
124 | Event::unloop; |
123 | EV::unloop; |
125 | }; |
124 | }; |
126 | }; |
125 | }; |
127 | |
126 | |
128 | # possibly queue up other requests, or open GUI windows, |
127 | # possibly queue up other requests, or open GUI windows, |
129 | # check for sockets etc. etc. |
128 | # check for sockets etc. etc. |
130 | |
129 | |
131 | # process events as long as there are some: |
130 | # process events as long as there are some: |
132 | Event::loop; |
131 | EV::loop; |
133 | |
132 | |
134 | =head1 REQUEST ANATOMY AND LIFETIME |
133 | =head1 REQUEST ANATOMY AND LIFETIME |
135 | |
134 | |
136 | Every C<aio_*> function creates a request. which is a C data structure not |
135 | Every C<aio_*> function creates a request. which is a C data structure not |
137 | directly visible to Perl. |
136 | directly visible to Perl. |
… | |
… | |
187 | |
186 | |
188 | package IO::AIO; |
187 | package IO::AIO; |
189 | |
188 | |
190 | use Carp (); |
189 | use Carp (); |
191 | |
190 | |
192 | no warnings; |
191 | use common::sense; |
193 | use strict 'vars'; |
|
|
194 | |
192 | |
195 | use base 'Exporter'; |
193 | use base 'Exporter'; |
196 | |
194 | |
197 | BEGIN { |
195 | BEGIN { |
198 | our $VERSION = '3.21'; |
196 | our $VERSION = '3.4'; |
199 | |
197 | |
200 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close |
198 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close |
201 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
199 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
202 | aio_scandir aio_symlink aio_readlink aio_sync aio_fsync |
200 | aio_scandir aio_symlink aio_readlink aio_sync aio_fsync |
203 | aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead |
201 | aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead |
204 | aio_rename aio_link aio_move aio_copy aio_group |
202 | aio_rename aio_link aio_move aio_copy aio_group |
205 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
203 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
206 | aio_chmod aio_utime aio_truncate); |
204 | aio_chmod aio_utime aio_truncate |
|
|
205 | aio_msync aio_mtouch); |
207 | |
206 | |
208 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
207 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
209 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
208 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
210 | min_parallel max_parallel max_idle |
209 | min_parallel max_parallel max_idle |
211 | nreqs nready npending nthreads |
210 | nreqs nready npending nthreads |
212 | max_poll_time max_poll_reqs); |
211 | max_poll_time max_poll_reqs |
|
|
212 | sendfile fadvise); |
213 | |
213 | |
214 | push @AIO_REQ, qw(aio_busy); # not exported |
214 | push @AIO_REQ, qw(aio_busy); # not exported |
215 | |
215 | |
216 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
216 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
217 | |
217 | |
… | |
… | |
381 | |
381 | |
382 | This call tries to make use of a native C<sendfile> syscall to provide |
382 | This call tries to make use of a native C<sendfile> syscall to provide |
383 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
383 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
384 | socket, and C<$in_fh> should refer to mmap'able file. |
384 | socket, and C<$in_fh> should refer to mmap'able file. |
385 | |
385 | |
386 | If the native sendfile call fails or is not implemented, it will be |
386 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
|
|
387 | C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>, |
387 | emulated, so you can call C<aio_sendfile> on any type of filehandle |
388 | it will be emulated, so you can call C<aio_sendfile> on any type of |
388 | regardless of the limitations of the operating system. |
389 | filehandle regardless of the limitations of the operating system. |
389 | |
390 | |
390 | Please note, however, that C<aio_sendfile> can read more bytes from |
391 | Please note, however, that C<aio_sendfile> can read more bytes from |
391 | C<$in_fh> than are written, and there is no way to find out how many |
392 | C<$in_fh> than are written, and there is no way to find out how many |
392 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
393 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
393 | provides the number of bytes written to C<$out_fh>. Only if the result |
394 | provides the number of bytes written to C<$out_fh>. Only if the result |
… | |
… | |
568 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to |
569 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to |
569 | know, you have to run stat yourself. Also, for speed reasons, the C<$type> |
570 | know, you have to run stat yourself. Also, for speed reasons, the C<$type> |
570 | scalars are read-only: you can not modify them. |
571 | scalars are read-only: you can not modify them. |
571 | |
572 | |
572 | C<$inode> is the inode number (which might not be exact on systems with 64 |
573 | C<$inode> is the inode number (which might not be exact on systems with 64 |
573 | bit inode numbers and 32 bit perls). On systems that do not deliver the |
574 | bit inode numbers and 32 bit perls). This field has unspecified content on |
574 | inode information, this will always be zero. |
575 | systems that do not deliver the inode information. |
575 | |
576 | |
576 | =item IO::AIO::READDIR_DIRS_FIRST |
577 | =item IO::AIO::READDIR_DIRS_FIRST |
577 | |
578 | |
578 | When this flag is set, then the names will be returned in an order where |
579 | When this flag is set, then the names will be returned in an order where |
579 | likely directories come first. This is useful when you need to quickly |
580 | likely directories come first. This is useful when you need to quickly |
… | |
… | |
635 | |
636 | |
636 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
637 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
637 | |
638 | |
638 | Try to copy the I<file> (directories not supported as either source or |
639 | Try to copy the I<file> (directories not supported as either source or |
639 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
640 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
640 | the C<0> (error) or C<-1> ok. |
641 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
641 | |
642 | |
642 | This is a composite request that creates the destination file with |
643 | This is a composite request that creates the destination file with |
643 | mode 0200 and copies the contents of the source file into it using |
644 | mode 0200 and copies the contents of the source file into it using |
644 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
645 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
645 | uid/gid, in that order. |
646 | uid/gid, in that order. |
… | |
… | |
657 | my $grp = aio_group $cb; |
658 | my $grp = aio_group $cb; |
658 | |
659 | |
659 | aioreq_pri $pri; |
660 | aioreq_pri $pri; |
660 | add $grp aio_open $src, O_RDONLY, 0, sub { |
661 | add $grp aio_open $src, O_RDONLY, 0, sub { |
661 | if (my $src_fh = $_[0]) { |
662 | if (my $src_fh = $_[0]) { |
662 | my @stat = stat $src_fh; # hmm, might bock over nfs? |
663 | my @stat = stat $src_fh; # hmm, might block over nfs? |
663 | |
664 | |
664 | aioreq_pri $pri; |
665 | aioreq_pri $pri; |
665 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
666 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
666 | if (my $dst_fh = $_[0]) { |
667 | if (my $dst_fh = $_[0]) { |
667 | aioreq_pri $pri; |
668 | aioreq_pri $pri; |
… | |
… | |
714 | |
715 | |
715 | =item aio_move $srcpath, $dstpath, $callback->($status) |
716 | =item aio_move $srcpath, $dstpath, $callback->($status) |
716 | |
717 | |
717 | Try to move the I<file> (directories not supported as either source or |
718 | Try to move the I<file> (directories not supported as either source or |
718 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
719 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
719 | the C<0> (error) or C<-1> ok. |
720 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
720 | |
721 | |
721 | This is a composite request that tries to rename(2) the file first; if |
722 | This is a composite request that tries to rename(2) the file first; if |
722 | rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if |
723 | rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if |
723 | that is successful, unlinks the C<$srcpath>. |
724 | that is successful, unlinks the C<$srcpath>. |
724 | |
725 | |
… | |
… | |
958 | (E.g. rename). This might not work on all operating systems or have any |
959 | (E.g. rename). This might not work on all operating systems or have any |
959 | specific effect, but usually it makes sure that directory changes get |
960 | specific effect, but usually it makes sure that directory changes get |
960 | written to disc. It works for anything that can be opened for read-only, |
961 | written to disc. It works for anything that can be opened for read-only, |
961 | not just directories. |
962 | not just directories. |
962 | |
963 | |
|
|
964 | Future versions of this function might fall back to other methods when |
|
|
965 | C<fsync> on the directory fails (such as calling C<sync>). |
|
|
966 | |
963 | Passes C<0> when everything went ok, and C<-1> on error. |
967 | Passes C<0> when everything went ok, and C<-1> on error. |
964 | |
968 | |
965 | =cut |
969 | =cut |
966 | |
970 | |
967 | sub aio_pathsync($;$) { |
971 | sub aio_pathsync($;$) { |
… | |
… | |
987 | }; |
991 | }; |
988 | |
992 | |
989 | $grp |
993 | $grp |
990 | } |
994 | } |
991 | |
995 | |
|
|
996 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
|
|
997 | |
|
|
998 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
|
|
999 | scalars (see the L<Sys::Mmap> or L<Mmap> modules for details on this, note |
|
|
1000 | that the scalar must only be modified in-place while an aio operation is |
|
|
1001 | pending on it). |
|
|
1002 | |
|
|
1003 | It calls the C<msync> function of your OS, if available, with the memory |
|
|
1004 | area starting at C<$offset> in the string and ending C<$length> bytes |
|
|
1005 | later. If C<$length> is negative, counts from the end, and if C<$length> |
|
|
1006 | is C<undef>, then it goes till the end of the string. The flags can be |
|
|
1007 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
|
|
1008 | C<IO::AIO::MS_SYNC>. |
|
|
1009 | |
|
|
1010 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
|
|
1011 | |
|
|
1012 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
|
|
1013 | scalars. |
|
|
1014 | |
|
|
1015 | It touches (reads or writes) all memory pages in the specified |
|
|
1016 | range inside the scalar. All caveats and parameters are the same |
|
|
1017 | as for C<aio_msync>, above, except for flags, which must be either |
|
|
1018 | C<0> (which reads all pages and ensures they are instantiated) or |
|
|
1019 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
|
|
1020 | writing an octet from it, which dirties the page). |
|
|
1021 | |
992 | =item aio_group $callback->(...) |
1022 | =item aio_group $callback->(...) |
993 | |
1023 | |
994 | This is a very special aio request: Instead of doing something, it is a |
1024 | This is a very special aio request: Instead of doing something, it is a |
995 | container for other aio requests, which is useful if you want to bundle |
1025 | container for other aio requests, which is useful if you want to bundle |
996 | many requests into a single, composite, request with a definite callback |
1026 | many requests into a single, composite, request with a definite callback |
… | |
… | |
1131 | =item $grp->cancel_subs |
1161 | =item $grp->cancel_subs |
1132 | |
1162 | |
1133 | Cancel all subrequests and clears any feeder, but not the group request |
1163 | Cancel all subrequests and clears any feeder, but not the group request |
1134 | itself. Useful when you queued a lot of events but got a result early. |
1164 | itself. Useful when you queued a lot of events but got a result early. |
1135 | |
1165 | |
|
|
1166 | The group request will finish normally (you cannot add requests to the |
|
|
1167 | group). |
|
|
1168 | |
1136 | =item $grp->result (...) |
1169 | =item $grp->result (...) |
1137 | |
1170 | |
1138 | Set the result value(s) that will be passed to the group callback when all |
1171 | Set the result value(s) that will be passed to the group callback when all |
1139 | subrequests have finished and set the groups errno to the current value |
1172 | subrequests have finished and set the groups errno to the current value |
1140 | of errno (just like calling C<errno> without an error number). By default, |
1173 | of errno (just like calling C<errno> without an error number). By default, |
… | |
… | |
1208 | =over 4 |
1241 | =over 4 |
1209 | |
1242 | |
1210 | =item $fileno = IO::AIO::poll_fileno |
1243 | =item $fileno = IO::AIO::poll_fileno |
1211 | |
1244 | |
1212 | Return the I<request result pipe file descriptor>. This filehandle must be |
1245 | Return the I<request result pipe file descriptor>. This filehandle must be |
1213 | polled for reading by some mechanism outside this module (e.g. Event or |
1246 | polled for reading by some mechanism outside this module (e.g. EV, Glib, |
1214 | select, see below or the SYNOPSIS). If the pipe becomes readable you have |
1247 | select and so on, see below or the SYNOPSIS). If the pipe becomes readable |
1215 | to call C<poll_cb> to check the results. |
1248 | you have to call C<poll_cb> to check the results. |
1216 | |
1249 | |
1217 | See C<poll_cb> for an example. |
1250 | See C<poll_cb> for an example. |
1218 | |
1251 | |
1219 | =item IO::AIO::poll_cb |
1252 | =item IO::AIO::poll_cb |
1220 | |
1253 | |
… | |
… | |
1227 | If not all requests were processed for whatever reason, the filehandle |
1260 | If not all requests were processed for whatever reason, the filehandle |
1228 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1261 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1229 | do anything special to have it called later. |
1262 | do anything special to have it called later. |
1230 | |
1263 | |
1231 | Example: Install an Event watcher that automatically calls |
1264 | Example: Install an Event watcher that automatically calls |
1232 | IO::AIO::poll_cb with high priority: |
1265 | IO::AIO::poll_cb with high priority (more examples can be found in the |
|
|
1266 | SYNOPSIS section, at the top of this document): |
1233 | |
1267 | |
1234 | Event->io (fd => IO::AIO::poll_fileno, |
1268 | Event->io (fd => IO::AIO::poll_fileno, |
1235 | poll => 'r', async => 1, |
1269 | poll => 'r', async => 1, |
1236 | cb => \&IO::AIO::poll_cb); |
1270 | cb => \&IO::AIO::poll_cb); |
1237 | |
1271 | |
… | |
… | |
1391 | |
1425 | |
1392 | =item IO::AIO::npending |
1426 | =item IO::AIO::npending |
1393 | |
1427 | |
1394 | Returns the number of requests currently in the pending state (executed, |
1428 | Returns the number of requests currently in the pending state (executed, |
1395 | but not yet processed by poll_cb). |
1429 | but not yet processed by poll_cb). |
|
|
1430 | |
|
|
1431 | =back |
|
|
1432 | |
|
|
1433 | =head3 MISCELLANEOUS FUNCTIONS |
|
|
1434 | |
|
|
1435 | IO::AIO implements some functions that might be useful, but are not |
|
|
1436 | asynchronous. |
|
|
1437 | |
|
|
1438 | =over 4 |
|
|
1439 | |
|
|
1440 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
|
|
1441 | |
|
|
1442 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
|
|
1443 | but is blocking (this makes most sense if you know the input data is |
|
|
1444 | likely cached already and the output filehandle is set to non-blocking |
|
|
1445 | operations). |
|
|
1446 | |
|
|
1447 | Returns the number of bytes copied, or C<-1> on error. |
|
|
1448 | |
|
|
1449 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
|
|
1450 | |
|
|
1451 | Simply calls the C<posix_fadvise> function (see it's |
|
|
1452 | manpage for details). The following advice constants are |
|
|
1453 | avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
|
|
1454 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
|
|
1455 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
|
|
1456 | |
|
|
1457 | On systems that do not implement C<posix_fadvise>, this function returns |
|
|
1458 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
1396 | |
1459 | |
1397 | =back |
1460 | =back |
1398 | |
1461 | |
1399 | =cut |
1462 | =cut |
1400 | |
1463 | |