… | |
… | |
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 | |
28 | |
29 | # AnyEvent integration |
29 | # AnyEvent integration (EV, Event, Glib, Tk, urxvt, pureperl...) |
30 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
30 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
31 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
31 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
|
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32 | |
|
|
33 | # EV integration |
|
|
34 | my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
32 | |
35 | |
33 | # Event integration |
36 | # Event integration |
34 | Event->io (fd => IO::AIO::poll_fileno, |
37 | Event->io (fd => IO::AIO::poll_fileno, |
35 | poll => 'r', |
38 | poll => 'r', |
36 | cb => \&IO::AIO::poll_cb); |
39 | cb => \&IO::AIO::poll_cb); |
… | |
… | |
61 | faster on a RAID volume or over NFS when you do a number of stat |
64 | faster on a RAID volume or over NFS when you do a number of stat |
62 | operations concurrently. |
65 | operations concurrently. |
63 | |
66 | |
64 | While most of this works on all types of file descriptors (for example |
67 | While most of this works on all types of file descriptors (for example |
65 | sockets), using these functions on file descriptors that support |
68 | sockets), using these functions on file descriptors that support |
66 | nonblocking operation (again, sockets, pipes etc.) is very inefficient |
69 | nonblocking operation (again, sockets, pipes etc.) is very inefficient. |
67 | or might not work (aio_read fails on sockets/pipes/fifos). Use an event |
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|
68 | loop for that (such as the Event module): IO::AIO will naturally fit |
70 | Use an event loop for that (such as the Event module): IO::AIO will |
69 | into such an event loop itself. |
71 | naturally fit into such an event loop itself. |
70 | |
72 | |
71 | 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 |
72 | requests and signal their completion. You don't need thread support in |
74 | requests and signal their completion. You don't need thread support in |
73 | perl, and the threads created by this module will not be visible to |
75 | perl, and the threads created by this module will not be visible to |
74 | perl. In the future, this module might make use of the native aio |
76 | perl. In the future, this module might make use of the native aio |
… | |
… | |
76 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
78 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
77 | files currently, for example), and they would only support aio_read and |
79 | files currently, for example), and they would only support aio_read and |
78 | aio_write, so the remaining functionality would have to be implemented |
80 | aio_write, so the remaining functionality would have to be implemented |
79 | using threads anyway. |
81 | using threads anyway. |
80 | |
82 | |
81 | Although the module will work with in the presence of other (Perl-) |
83 | Although the module will work in the presence of other (Perl-) threads, |
82 | threads, it is currently not reentrant in any way, so use appropriate |
84 | it is currently not reentrant in any way, so use appropriate locking |
83 | locking yourself, always call "poll_cb" from within the same thread, or |
85 | yourself, always call "poll_cb" from within the same thread, or never |
84 | never call "poll_cb" (or other "aio_" functions) recursively. |
86 | call "poll_cb" (or other "aio_" functions) recursively. |
85 | |
87 | |
86 | EXAMPLE |
88 | EXAMPLE |
87 | This is a simple example that uses the Event module and loads |
89 | This is a simple example that uses the Event module and loads |
88 | /etc/passwd asynchronously: |
90 | /etc/passwd asynchronously: |
89 | |
91 | |
… | |
… | |
242 | They are the same as used by "sysopen". |
244 | They are the same as used by "sysopen". |
243 | |
245 | |
244 | Likewise, $mode specifies the mode of the newly created file, if it |
246 | Likewise, $mode specifies the mode of the newly created file, if it |
245 | didn't exist and "O_CREAT" has been given, just like perl's |
247 | didn't exist and "O_CREAT" has been given, just like perl's |
246 | "sysopen", except that it is mandatory (i.e. use 0 if you don't |
248 | "sysopen", except that it is mandatory (i.e. use 0 if you don't |
247 | create new files, and 0666 or 0777 if you do). |
249 | create new files, and 0666 or 0777 if you do). Note that the $mode |
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250 | will be modified by the umask in effect then the request is being |
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251 | executed, so better never change the umask. |
248 | |
252 | |
249 | Example: |
253 | Example: |
250 | |
254 | |
251 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
255 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
252 | if ($_[0]) { |
256 | if ($_[0]) { |
… | |
… | |
257 | } |
261 | } |
258 | }; |
262 | }; |
259 | |
263 | |
260 | aio_close $fh, $callback->($status) |
264 | aio_close $fh, $callback->($status) |
261 | Asynchronously close a file and call the callback with the result |
265 | Asynchronously close a file and call the callback with the result |
262 | code. *WARNING:* although accepted, you should not pass in a perl |
266 | code. |
263 | filehandle here, as perl will likely close the file descriptor |
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264 | another time when the filehandle is destroyed. Normally, you can |
|
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265 | safely call perls "close" or just let filehandles go out of scope. |
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266 | |
267 | |
267 | This is supposed to be a bug in the API, so that might change. It's |
268 | Unfortunately, you can't do this to perl. Perl *insists* very |
268 | therefore best to avoid this function. |
269 | strongly on closing the file descriptor associated with the |
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270 | filehandle itself. |
|
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271 | |
|
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272 | Therefore, "aio_close" will not close the filehandle - instead it |
|
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273 | will use dup2 to overwrite the file descriptor with the write-end of |
|
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274 | a pipe (the pipe fd will be created on demand and will be cached). |
|
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275 | |
|
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276 | Or in other words: the file descriptor will be closed, but it will |
|
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277 | not be free for reuse until the perl filehandle is closed. |
269 | |
278 | |
270 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
279 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
271 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
280 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
272 | Reads or writes "length" bytes from the specified "fh" and "offset" |
281 | Reads or writes $length bytes from the specified $fh and $offset |
273 | into the scalar given by "data" and offset "dataoffset" and calls |
282 | into the scalar given by $data and offset $dataoffset and calls the |
274 | the callback without the actual number of bytes read (or -1 on |
283 | callback without the actual number of bytes read (or -1 on error, |
275 | error, just like the syscall). |
284 | just like the syscall). |
|
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285 | |
|
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286 | If $offset is undefined, then the current file descriptor offset |
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287 | will be used (and updated), otherwise the file descriptor offset |
|
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288 | will not be changed by these calls. |
|
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289 | |
|
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290 | If $length is undefined in "aio_write", use the remaining length of |
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291 | $data. |
|
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292 | |
|
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293 | If $dataoffset is less than zero, it will be counted from the end of |
|
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294 | $data. |
276 | |
295 | |
277 | The $data scalar *MUST NOT* be modified in any way while the request |
296 | The $data scalar *MUST NOT* be modified in any way while the request |
278 | is outstanding. Modifying it can result in segfaults or WW3 (if the |
297 | is outstanding. Modifying it can result in segfaults or World War |
279 | necessary/optional hardware is installed). |
298 | III (if the necessary/optional hardware is installed). |
280 | |
299 | |
281 | Example: Read 15 bytes at offset 7 into scalar $buffer, starting at |
300 | Example: Read 15 bytes at offset 7 into scalar $buffer, starting at |
282 | offset 0 within the scalar: |
301 | offset 0 within the scalar: |
283 | |
302 | |
284 | aio_read $fh, 7, 15, $buffer, 0, sub { |
303 | aio_read $fh, 7, 15, $buffer, 0, sub { |
… | |
… | |
342 | aio_stat "/etc/passwd", sub { |
361 | aio_stat "/etc/passwd", sub { |
343 | $_[0] and die "stat failed: $!"; |
362 | $_[0] and die "stat failed: $!"; |
344 | print "size is ", -s _, "\n"; |
363 | print "size is ", -s _, "\n"; |
345 | }; |
364 | }; |
346 | |
365 | |
|
|
366 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
|
|
367 | Works like perl's "utime" function (including the special case of |
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368 | $atime and $mtime being undef). Fractional times are supported if |
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369 | the underlying syscalls support them. |
|
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370 | |
|
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371 | When called with a pathname, uses utimes(2) if available, otherwise |
|
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372 | utime(2). If called on a file descriptor, uses futimes(2) if |
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373 | available, otherwise returns ENOSYS, so this is not portable. |
|
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374 | |
|
|
375 | Examples: |
|
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376 | |
|
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377 | # set atime and mtime to current time (basically touch(1)): |
|
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378 | aio_utime "path", undef, undef; |
|
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379 | # set atime to current time and mtime to beginning of the epoch: |
|
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380 | aio_utime "path", time, undef; # undef==0 |
|
|
381 | |
|
|
382 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
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383 | Works like perl's "chown" function, except that "undef" for either |
|
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384 | $uid or $gid is being interpreted as "do not change" (but -1 can |
|
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385 | also be used). |
|
|
386 | |
|
|
387 | Examples: |
|
|
388 | |
|
|
389 | # same as "chown root path" in the shell: |
|
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390 | aio_chown "path", 0, -1; |
|
|
391 | # same as above: |
|
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392 | aio_chown "path", 0, undef; |
|
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393 | |
|
|
394 | aio_truncate $fh_or_path, $offset, $callback->($status) |
|
|
395 | Works like truncate(2) or ftruncate(2). |
|
|
396 | |
|
|
397 | aio_chmod $fh_or_path, $mode, $callback->($status) |
|
|
398 | Works like perl's "chmod" function. |
|
|
399 | |
347 | aio_unlink $pathname, $callback->($status) |
400 | aio_unlink $pathname, $callback->($status) |
348 | Asynchronously unlink (delete) a file and call the callback with the |
401 | Asynchronously unlink (delete) a file and call the callback with the |
349 | result code. |
402 | result code. |
350 | |
403 | |
351 | aio_mknod $path, $mode, $dev, $callback->($status) |
404 | aio_mknod $path, $mode, $dev, $callback->($status) |
… | |
… | |
373 | |
426 | |
374 | aio_rename $srcpath, $dstpath, $callback->($status) |
427 | aio_rename $srcpath, $dstpath, $callback->($status) |
375 | Asynchronously rename the object at $srcpath to $dstpath, just as |
428 | Asynchronously rename the object at $srcpath to $dstpath, just as |
376 | rename(2) and call the callback with the result code. |
429 | rename(2) and call the callback with the result code. |
377 | |
430 | |
|
|
431 | aio_mkdir $pathname, $mode, $callback->($status) |
|
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432 | Asynchronously mkdir (create) a directory and call the callback with |
|
|
433 | the result code. $mode will be modified by the umask at the time the |
|
|
434 | request is executed, so do not change your umask. |
|
|
435 | |
378 | aio_rmdir $pathname, $callback->($status) |
436 | aio_rmdir $pathname, $callback->($status) |
379 | Asynchronously rmdir (delete) a directory and call the callback with |
437 | Asynchronously rmdir (delete) a directory and call the callback with |
380 | the result code. |
438 | the result code. |
381 | |
439 | |
382 | aio_readdir $pathname, $callback->($entries) |
440 | aio_readdir $pathname, $callback->($entries) |
… | |
… | |
384 | entire directory (i.e. opendir + readdir + closedir). The entries |
442 | entire directory (i.e. opendir + readdir + closedir). The entries |
385 | will not be sorted, and will NOT include the "." and ".." entries. |
443 | will not be sorted, and will NOT include the "." and ".." entries. |
386 | |
444 | |
387 | The callback a single argument which is either "undef" or an |
445 | The callback a single argument which is either "undef" or an |
388 | array-ref with the filenames. |
446 | array-ref with the filenames. |
|
|
447 | |
|
|
448 | aio_load $path, $data, $callback->($status) |
|
|
449 | This is a composite request that tries to fully load the given file |
|
|
450 | into memory. Status is the same as with aio_read. |
389 | |
451 | |
390 | aio_copy $srcpath, $dstpath, $callback->($status) |
452 | aio_copy $srcpath, $dstpath, $callback->($status) |
391 | Try to copy the *file* (directories not supported as either source |
453 | Try to copy the *file* (directories not supported as either source |
392 | or destination) from $srcpath to $dstpath and call the callback with |
454 | or destination) from $srcpath to $dstpath and call the callback with |
393 | the 0 (error) or -1 ok. |
455 | the 0 (error) or -1 ok. |
… | |
… | |
461 | |
523 | |
462 | It will also likely work on non-POSIX filesystems with reduced |
524 | It will also likely work on non-POSIX filesystems with reduced |
463 | efficiency as those tend to return 0 or 1 as link counts, which |
525 | efficiency as those tend to return 0 or 1 as link counts, which |
464 | disables the directory counting heuristic. |
526 | disables the directory counting heuristic. |
465 | |
527 | |
|
|
528 | aio_rmtree $path, $callback->($status) |
|
|
529 | Delete a directory tree starting (and including) $path, return the |
|
|
530 | status of the final "rmdir" only. This is a composite request that |
|
|
531 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
|
|
532 | everything else. |
|
|
533 | |
|
|
534 | aio_sync $callback->($status) |
|
|
535 | Asynchronously call sync and call the callback when finished. |
|
|
536 | |
466 | aio_fsync $fh, $callback->($status) |
537 | aio_fsync $fh, $callback->($status) |
467 | Asynchronously call fsync on the given filehandle and call the |
538 | Asynchronously call fsync on the given filehandle and call the |
468 | callback with the fsync result code. |
539 | callback with the fsync result code. |
469 | |
540 | |
470 | aio_fdatasync $fh, $callback->($status) |
541 | aio_fdatasync $fh, $callback->($status) |
471 | Asynchronously call fdatasync on the given filehandle and call the |
542 | Asynchronously call fdatasync on the given filehandle and call the |
472 | callback with the fdatasync result code. |
543 | callback with the fdatasync result code. |
473 | |
544 | |
474 | If this call isn't available because your OS lacks it or it couldn't |
545 | If this call isn't available because your OS lacks it or it couldn't |
475 | be detected, it will be emulated by calling "fsync" instead. |
546 | be detected, it will be emulated by calling "fsync" instead. |
|
|
547 | |
|
|
548 | aio_pathsync $path, $callback->($status) |
|
|
549 | This request tries to open, fsync and close the given path. This is |
|
|
550 | a composite request intended tosync directories after directory |
|
|
551 | operations (E.g. rename). This might not work on all operating |
|
|
552 | systems or have any specific effect, but usually it makes sure that |
|
|
553 | directory changes get written to disc. It works for anything that |
|
|
554 | can be opened for read-only, not just directories. |
|
|
555 | |
|
|
556 | Passes 0 when everything went ok, and -1 on error. |
476 | |
557 | |
477 | aio_group $callback->(...) |
558 | aio_group $callback->(...) |
478 | This is a very special aio request: Instead of doing something, it |
559 | This is a very special aio request: Instead of doing something, it |
479 | is a container for other aio requests, which is useful if you want |
560 | is a container for other aio requests, which is useful if you want |
480 | to bundle many requests into a single, composite, request with a |
561 | to bundle many requests into a single, composite, request with a |
… | |
… | |
562 | }; |
643 | }; |
563 | |
644 | |
564 | This makes it very easy to create composite requests (see the source of |
645 | This makes it very easy to create composite requests (see the source of |
565 | "aio_move" for an application) that work and feel like simple requests. |
646 | "aio_move" for an application) that work and feel like simple requests. |
566 | |
647 | |
567 | * The IO::AIO::GRP objects will be cleaned up during calls to |
648 | * The IO::AIO::GRP objects will be cleaned up during calls to |
568 | "IO::AIO::poll_cb", just like any other request. |
649 | "IO::AIO::poll_cb", just like any other request. |
|
|
650 | |
569 | * They can be canceled like any other request. Canceling will cancel not |
651 | * They can be canceled like any other request. Canceling will cancel |
570 | only the request itself, but also all requests it contains. |
652 | not only the request itself, but also all requests it contains. |
|
|
653 | |
571 | * They can also can also be added to other IO::AIO::GRP objects. |
654 | * They can also can also be added to other IO::AIO::GRP objects. |
|
|
655 | |
572 | * You must not add requests to a group from within the group callback |
656 | * You must not add requests to a group from within the group callback |
573 | (or any later time). |
657 | (or any later time). |
574 | |
658 | |
575 | Their lifetime, simplified, looks like this: when they are empty, they |
659 | Their lifetime, simplified, looks like this: when they are empty, they |
576 | will finish very quickly. If they contain only requests that are in the |
660 | will finish very quickly. If they contain only requests that are in the |
577 | "done" state, they will also finish. Otherwise they will continue to |
661 | "done" state, they will also finish. Otherwise they will continue to |
578 | exist. |
662 | exist. |
… | |
… | |
595 | request itself. Useful when you queued a lot of events but got a |
679 | request itself. Useful when you queued a lot of events but got a |
596 | result early. |
680 | result early. |
597 | |
681 | |
598 | $grp->result (...) |
682 | $grp->result (...) |
599 | Set the result value(s) that will be passed to the group callback |
683 | Set the result value(s) that will be passed to the group callback |
600 | when all subrequests have finished and set thre groups errno to the |
684 | when all subrequests have finished and set the groups errno to the |
601 | current value of errno (just like calling "errno" without an error |
685 | current value of errno (just like calling "errno" without an error |
602 | number). By default, no argument will be passed and errno is zero. |
686 | number). By default, no argument will be passed and errno is zero. |
603 | |
687 | |
604 | $grp->errno ([$errno]) |
688 | $grp->errno ([$errno]) |
605 | Sets the group errno value to $errno, or the current value of errno |
689 | Sets the group errno value to $errno, or the current value of errno |
… | |
… | |
791 | $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
875 | $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
792 | This is a very bad function to use in interactive programs because |
876 | This is a very bad function to use in interactive programs because |
793 | it blocks, and a bad way to reduce concurrency because it is |
877 | it blocks, and a bad way to reduce concurrency because it is |
794 | inexact: Better use an "aio_group" together with a feed callback. |
878 | inexact: Better use an "aio_group" together with a feed callback. |
795 | |
879 | |
796 | Sets the maximum number of outstanding requests to $nreqs. If you to |
880 | Sets the maximum number of outstanding requests to $nreqs. If you do |
797 | queue up more than this number of requests, the next call to the |
881 | queue up more than this number of requests, the next call to the |
798 | "poll_cb" (and "poll_some" and other functions calling "poll_cb") |
882 | "poll_cb" (and "poll_some" and other functions calling "poll_cb") |
799 | function will block until the limit is no longer exceeded. |
883 | function will block until the limit is no longer exceeded. |
800 | |
884 | |
801 | The default value is very large, so there is no practical limit on |
885 | The default value is very large, so there is no practical limit on |
… | |
… | |
847 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
931 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
848 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
932 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
849 | scalars and other data passed into aio requests will also be locked and |
933 | scalars and other data passed into aio requests will also be locked and |
850 | will consume memory till the request has entered the done state. |
934 | will consume memory till the request has entered the done state. |
851 | |
935 | |
852 | This is now awfully much, so queuing lots of requests is not usually a |
936 | This is not awfully much, so queuing lots of requests is not usually a |
853 | problem. |
937 | problem. |
854 | |
938 | |
855 | Per-thread usage: |
939 | Per-thread usage: |
856 | |
940 | |
857 | In the execution phase, some aio requests require more memory for |
941 | In the execution phase, some aio requests require more memory for |