… | |
… | |
61 | etc.), but can also be used to easily do operations in parallel that are |
61 | etc.), but can also be used to easily do operations in parallel that are |
62 | normally done sequentially, e.g. stat'ing many files, which is much faster |
62 | normally done sequentially, e.g. stat'ing many files, which is much faster |
63 | on a RAID volume or over NFS when you do a number of stat operations |
63 | on a RAID volume or over NFS when you do a number of stat operations |
64 | concurrently. |
64 | concurrently. |
65 | |
65 | |
66 | While this works on all types of file descriptors (for example sockets), |
66 | While most of this works on all types of file descriptors (for example |
67 | using these functions on file descriptors that support nonblocking |
67 | sockets), using these functions on file descriptors that support |
68 | operation (again, sockets, pipes etc.) is very inefficient. Use an event |
68 | nonblocking operation (again, sockets, pipes etc.) is very inefficient or |
|
|
69 | might not work (aio_read fails on sockets/pipes/fifos). Use an event loop |
69 | loop for that (such as the L<Event|Event> module): IO::AIO will naturally |
70 | for that (such as the L<Event|Event> module): IO::AIO will naturally fit |
70 | fit into such an event loop itself. |
71 | into such an event loop itself. |
71 | |
72 | |
72 | In this version, a number of threads are started that execute your |
73 | In this version, a number of threads are started that execute your |
73 | requests and signal their completion. You don't need thread support |
74 | requests and signal their completion. You don't need thread support |
74 | in perl, and the threads created by this module will not be visible |
75 | in perl, and the threads created by this module will not be visible |
75 | to perl. In the future, this module might make use of the native aio |
76 | to perl. In the future, this module might make use of the native aio |
… | |
… | |
192 | BEGIN { |
193 | BEGIN { |
193 | our $VERSION = '2.1'; |
194 | our $VERSION = '2.1'; |
194 | |
195 | |
195 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
196 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
196 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
197 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
197 | aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move |
198 | aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link |
198 | aio_copy aio_group aio_nop aio_mknod); |
199 | aio_move aio_copy aio_group aio_nop aio_mknod); |
199 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
200 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
200 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
201 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
201 | min_parallel max_parallel max_idle |
202 | min_parallel max_parallel max_idle |
202 | nreqs nready npending nthreads |
203 | nreqs nready npending nthreads |
203 | max_poll_time max_poll_reqs); |
204 | max_poll_time max_poll_reqs); |
… | |
… | |
416 | |
417 | |
417 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
418 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
418 | |
419 | |
419 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
420 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
420 | the path C<$dstpath> and call the callback with the result code. |
421 | the path C<$dstpath> and call the callback with the result code. |
|
|
422 | |
|
|
423 | =item aio_readlink $path, $callback->($link) |
|
|
424 | |
|
|
425 | Asynchronously read the symlink specified by C<$path> and pass it to |
|
|
426 | the callback. If an error occurs, nothing or undef gets passed to the |
|
|
427 | callback. |
421 | |
428 | |
422 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
429 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
423 | |
430 | |
424 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
431 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
425 | rename(2) and call the callback with the result code. |
432 | rename(2) and call the callback with the result code. |
… | |
… | |
939 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
946 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
940 | the maximum amount of time (default C<0>, meaning infinity) spent in |
947 | the maximum amount of time (default C<0>, meaning infinity) spent in |
941 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
948 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
942 | of time C<poll_cb> is allowed to use). |
949 | of time C<poll_cb> is allowed to use). |
943 | |
950 | |
|
|
951 | Setting C<max_poll_time> to a non-zero value creates an overhead of one |
|
|
952 | syscall per request processed, which is not normally a problem unless your |
|
|
953 | callbacks are really really fast or your OS is really really slow (I am |
|
|
954 | not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead. |
|
|
955 | |
944 | Setting these is useful if you want to ensure some level of |
956 | Setting these is useful if you want to ensure some level of |
945 | interactiveness when perl is not fast enough to process all requests in |
957 | interactiveness when perl is not fast enough to process all requests in |
946 | time. |
958 | time. |
947 | |
959 | |
948 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
960 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
949 | |
961 | |
950 | Example: Install an Event watcher that automatically calls |
962 | Example: Install an Event watcher that automatically calls |
951 | IO::AIO::poll_some with low priority, to ensure that other parts of the |
963 | IO::AIO::poll_cb with low priority, to ensure that other parts of the |
952 | program get the CPU sometimes even under high AIO load. |
964 | program get the CPU sometimes even under high AIO load. |
953 | |
965 | |
954 | # try not to spend much more than 0.1s in poll_cb |
966 | # try not to spend much more than 0.1s in poll_cb |
955 | IO::AIO::max_poll_time 0.1; |
967 | IO::AIO::max_poll_time 0.1; |
956 | |
968 | |