… | |
… | |
62 | etc.), but can also be used to easily do operations in parallel that are |
62 | etc.), but can also be used to easily do operations in parallel that are |
63 | normally done sequentially, e.g. stat'ing many files, which is much faster |
63 | normally done sequentially, e.g. stat'ing many files, which is much faster |
64 | on a RAID volume or over NFS when you do a number of stat operations |
64 | on a RAID volume or over NFS when you do a number of stat operations |
65 | concurrently. |
65 | concurrently. |
66 | |
66 | |
67 | 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 |
68 | sockets), using these functions on file descriptors that support |
68 | example sockets), using these functions on file descriptors that |
69 | nonblocking operation (again, sockets, pipes etc.) is very inefficient or |
69 | support nonblocking operation (again, sockets, pipes etc.) is very |
70 | might not work (aio_read fails on sockets/pipes/fifos). Use an event loop |
70 | inefficient. Use an event loop for that (such as the L<Event|Event> |
71 | for that (such as the L<Event|Event> module): IO::AIO will naturally fit |
71 | module): IO::AIO will naturally fit into such an event loop itself. |
72 | into such an event loop itself. |
|
|
73 | |
72 | |
74 | 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 |
75 | requests and signal their completion. You don't need thread support |
74 | requests and signal their completion. You don't need thread support |
76 | 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 |
77 | 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 |
… | |
… | |
79 | 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 |
80 | 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 |
81 | aio_write, so the remaining functionality would have to be implemented |
80 | aio_write, so the remaining functionality would have to be implemented |
82 | using threads anyway. |
81 | using threads anyway. |
83 | |
82 | |
84 | 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, |
85 | 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 |
86 | locking yourself, always call C<poll_cb> from within the same thread, or |
85 | yourself, always call C<poll_cb> from within the same thread, or never |
87 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
86 | call C<poll_cb> (or other C<aio_> functions) recursively. |
88 | |
87 | |
89 | =head2 EXAMPLE |
88 | =head2 EXAMPLE |
90 | |
89 | |
91 | This is a simple example that uses the Event module and loads |
90 | This is a simple example that uses the Event module and loads |
92 | F</etc/passwd> asynchronously: |
91 | F</etc/passwd> asynchronously: |
… | |
… | |
184 | |
183 | |
185 | =cut |
184 | =cut |
186 | |
185 | |
187 | package IO::AIO; |
186 | package IO::AIO; |
188 | |
187 | |
|
|
188 | use Carp (); |
|
|
189 | |
189 | no warnings; |
190 | no warnings; |
190 | use strict 'vars'; |
191 | use strict 'vars'; |
191 | |
192 | |
192 | use base 'Exporter'; |
193 | use base 'Exporter'; |
193 | |
194 | |
194 | BEGIN { |
195 | BEGIN { |
195 | our $VERSION = '2.33'; |
196 | our $VERSION = '2.51'; |
196 | |
197 | |
197 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
198 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
198 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
199 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
199 | aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link |
200 | aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link |
200 | aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir); |
201 | aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir |
|
|
202 | aio_chown aio_chmod aio_utime aio_truncate); |
201 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); |
203 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); |
202 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
204 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
203 | min_parallel max_parallel max_idle |
205 | min_parallel max_parallel max_idle |
204 | nreqs nready npending nthreads |
206 | nreqs nready npending nthreads |
205 | max_poll_time max_poll_reqs); |
207 | max_poll_time max_poll_reqs); |
… | |
… | |
271 | aio_read $_[0], ..., sub { |
273 | aio_read $_[0], ..., sub { |
272 | ... |
274 | ... |
273 | }; |
275 | }; |
274 | }; |
276 | }; |
275 | |
277 | |
|
|
278 | |
276 | =item aioreq_nice $pri_adjust |
279 | =item aioreq_nice $pri_adjust |
277 | |
280 | |
278 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
281 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
279 | priority, so the effect is cumulative. |
282 | priority, so the effect is cumulative. |
|
|
283 | |
280 | |
284 | |
281 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
285 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
282 | |
286 | |
283 | Asynchronously open or create a file and call the callback with a newly |
287 | Asynchronously open or create a file and call the callback with a newly |
284 | created filehandle for the file. |
288 | created filehandle for the file. |
… | |
… | |
305 | } else { |
309 | } else { |
306 | die "open failed: $!\n"; |
310 | die "open failed: $!\n"; |
307 | } |
311 | } |
308 | }; |
312 | }; |
309 | |
313 | |
|
|
314 | |
310 | =item aio_close $fh, $callback->($status) |
315 | =item aio_close $fh, $callback->($status) |
311 | |
316 | |
312 | Asynchronously close a file and call the callback with the result |
317 | Asynchronously close a file and call the callback with the result |
313 | code. I<WARNING:> although accepted, you should not pass in a perl |
318 | code. |
314 | filehandle here, as perl will likely close the file descriptor another |
|
|
315 | time when the filehandle is destroyed. Normally, you can safely call perls |
|
|
316 | C<close> or just let filehandles go out of scope. |
|
|
317 | |
319 | |
318 | This is supposed to be a bug in the API, so that might change. It's |
320 | Unfortunately, you can't do this to perl. Perl I<insists> very strongly on |
319 | therefore best to avoid this function. |
321 | closing the file descriptor associated with the filehandle itself. Here is |
|
|
322 | what aio_close will try: |
|
|
323 | |
|
|
324 | 1. dup()licate the fd |
|
|
325 | 2. asynchronously close() the duplicated fd |
|
|
326 | 3. dup()licate the fd once more |
|
|
327 | 4. let perl close() the filehandle |
|
|
328 | 5. asynchronously close the duplicated fd |
|
|
329 | |
|
|
330 | The idea is that the first close() flushes stuff to disk that closing an |
|
|
331 | fd will flush, so when perl closes the fd, nothing much will need to be |
|
|
332 | flushed. The second async. close() will then flush stuff to disk that |
|
|
333 | closing the last fd to the file will flush. |
|
|
334 | |
|
|
335 | Just FYI, SuSv3 has this to say on close: |
|
|
336 | |
|
|
337 | All outstanding record locks owned by the process on the file |
|
|
338 | associated with the file descriptor shall be removed. |
|
|
339 | |
|
|
340 | If fildes refers to a socket, close() shall cause the socket to be |
|
|
341 | destroyed. ... close() shall block for up to the current linger |
|
|
342 | interval until all data is transmitted. |
|
|
343 | [this actually sounds like a specification bug, but who knows] |
|
|
344 | |
|
|
345 | And at least Linux additionally actually flushes stuff on every close, |
|
|
346 | even when the file itself is still open. |
|
|
347 | |
|
|
348 | Sounds enourmously inefficient and complicated? Yes... please show me how |
|
|
349 | to nuke perl's fd out of existence... |
|
|
350 | |
|
|
351 | =cut |
|
|
352 | |
|
|
353 | sub aio_close($;$) { |
|
|
354 | aio_block { |
|
|
355 | my ($fh, $cb) = @_; |
|
|
356 | |
|
|
357 | my $pri = aioreq_pri; |
|
|
358 | my $grp = aio_group $cb; |
|
|
359 | |
|
|
360 | my $fd = fileno $fh; |
|
|
361 | |
|
|
362 | defined $fd or Carp::croak "aio_close called with fd-less filehandle"; |
|
|
363 | |
|
|
364 | # if the dups fail we will simply get EBADF |
|
|
365 | my $fd2 = _dup $fd; |
|
|
366 | aioreq_pri $pri; |
|
|
367 | add $grp _aio_close $fd2, sub { |
|
|
368 | my $fd2 = _dup $fd; |
|
|
369 | close $fh; |
|
|
370 | aioreq_pri $pri; |
|
|
371 | add $grp _aio_close $fd2, sub { |
|
|
372 | $grp->result ($_[0]); |
|
|
373 | }; |
|
|
374 | }; |
|
|
375 | |
|
|
376 | $grp |
|
|
377 | } |
|
|
378 | } |
|
|
379 | |
320 | |
380 | |
321 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
381 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
322 | |
382 | |
323 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
383 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
324 | |
384 | |
325 | Reads or writes C<length> bytes from the specified C<fh> and C<offset> |
385 | Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset> |
326 | into the scalar given by C<data> and offset C<dataoffset> and calls the |
386 | into the scalar given by C<$data> and offset C<$dataoffset> and calls the |
327 | callback without the actual number of bytes read (or -1 on error, just |
387 | callback without the actual number of bytes read (or -1 on error, just |
328 | like the syscall). |
388 | like the syscall). |
329 | |
389 | |
|
|
390 | If C<$offset> is undefined, then the current file descriptor offset will |
|
|
391 | be used (and updated), otherwise the file descriptor offset will not be |
|
|
392 | changed by these calls. |
|
|
393 | |
|
|
394 | If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. |
|
|
395 | |
|
|
396 | If C<$dataoffset> is less than zero, it will be counted from the end of |
|
|
397 | C<$data>. |
|
|
398 | |
330 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
399 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
331 | is outstanding. Modifying it can result in segfaults or WW3 (if the |
400 | is outstanding. Modifying it can result in segfaults or World War III (if |
332 | necessary/optional hardware is installed). |
401 | the necessary/optional hardware is installed). |
333 | |
402 | |
334 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
403 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
335 | offset C<0> within the scalar: |
404 | offset C<0> within the scalar: |
336 | |
405 | |
337 | aio_read $fh, 7, 15, $buffer, 0, sub { |
406 | aio_read $fh, 7, 15, $buffer, 0, sub { |
338 | $_[0] > 0 or die "read error: $!"; |
407 | $_[0] > 0 or die "read error: $!"; |
339 | print "read $_[0] bytes: <$buffer>\n"; |
408 | print "read $_[0] bytes: <$buffer>\n"; |
340 | }; |
409 | }; |
|
|
410 | |
341 | |
411 | |
342 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
412 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
343 | |
413 | |
344 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
414 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
345 | reading at byte offset C<$in_offset>, and starts writing at the current |
415 | reading at byte offset C<$in_offset>, and starts writing at the current |
… | |
… | |
359 | C<$in_fh> than are written, and there is no way to find out how many |
429 | C<$in_fh> than are written, and there is no way to find out how many |
360 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
430 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
361 | provides the number of bytes written to C<$out_fh>. Only if the result |
431 | provides the number of bytes written to C<$out_fh>. Only if the result |
362 | value equals C<$length> one can assume that C<$length> bytes have been |
432 | value equals C<$length> one can assume that C<$length> bytes have been |
363 | read. |
433 | read. |
|
|
434 | |
364 | |
435 | |
365 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
436 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
366 | |
437 | |
367 | C<aio_readahead> populates the page cache with data from a file so that |
438 | C<aio_readahead> populates the page cache with data from a file so that |
368 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
439 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
… | |
… | |
374 | file. The current file offset of the file is left unchanged. |
445 | file. The current file offset of the file is left unchanged. |
375 | |
446 | |
376 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
447 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
377 | emulated by simply reading the data, which would have a similar effect. |
448 | emulated by simply reading the data, which would have a similar effect. |
378 | |
449 | |
|
|
450 | |
379 | =item aio_stat $fh_or_path, $callback->($status) |
451 | =item aio_stat $fh_or_path, $callback->($status) |
380 | |
452 | |
381 | =item aio_lstat $fh, $callback->($status) |
453 | =item aio_lstat $fh, $callback->($status) |
382 | |
454 | |
383 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
455 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
… | |
… | |
396 | aio_stat "/etc/passwd", sub { |
468 | aio_stat "/etc/passwd", sub { |
397 | $_[0] and die "stat failed: $!"; |
469 | $_[0] and die "stat failed: $!"; |
398 | print "size is ", -s _, "\n"; |
470 | print "size is ", -s _, "\n"; |
399 | }; |
471 | }; |
400 | |
472 | |
|
|
473 | |
|
|
474 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
|
|
475 | |
|
|
476 | Works like perl's C<utime> function (including the special case of $atime |
|
|
477 | and $mtime being undef). Fractional times are supported if the underlying |
|
|
478 | syscalls support them. |
|
|
479 | |
|
|
480 | When called with a pathname, uses utimes(2) if available, otherwise |
|
|
481 | utime(2). If called on a file descriptor, uses futimes(2) if available, |
|
|
482 | otherwise returns ENOSYS, so this is not portable. |
|
|
483 | |
|
|
484 | Examples: |
|
|
485 | |
|
|
486 | # set atime and mtime to current time (basically touch(1)): |
|
|
487 | aio_utime "path", undef, undef; |
|
|
488 | # set atime to current time and mtime to beginning of the epoch: |
|
|
489 | aio_utime "path", time, undef; # undef==0 |
|
|
490 | |
|
|
491 | |
|
|
492 | =item aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
|
493 | |
|
|
494 | Works like perl's C<chown> function, except that C<undef> for either $uid |
|
|
495 | or $gid is being interpreted as "do not change" (but -1 can also be used). |
|
|
496 | |
|
|
497 | Examples: |
|
|
498 | |
|
|
499 | # same as "chown root path" in the shell: |
|
|
500 | aio_chown "path", 0, -1; |
|
|
501 | # same as above: |
|
|
502 | aio_chown "path", 0, undef; |
|
|
503 | |
|
|
504 | |
|
|
505 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
|
|
506 | |
|
|
507 | Works like truncate(2) or ftruncate(2). |
|
|
508 | |
|
|
509 | |
|
|
510 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
|
|
511 | |
|
|
512 | Works like perl's C<chmod> function. |
|
|
513 | |
|
|
514 | |
401 | =item aio_unlink $pathname, $callback->($status) |
515 | =item aio_unlink $pathname, $callback->($status) |
402 | |
516 | |
403 | Asynchronously unlink (delete) a file and call the callback with the |
517 | Asynchronously unlink (delete) a file and call the callback with the |
404 | result code. |
518 | result code. |
405 | |
519 | |
|
|
520 | |
406 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
521 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
407 | |
522 | |
408 | [EXPERIMENTAL] |
523 | [EXPERIMENTAL] |
409 | |
524 | |
410 | Asynchronously create a device node (or fifo). See mknod(2). |
525 | Asynchronously create a device node (or fifo). See mknod(2). |
411 | |
526 | |
412 | The only (POSIX-) portable way of calling this function is: |
527 | The only (POSIX-) portable way of calling this function is: |
413 | |
528 | |
414 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
529 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
|
|
530 | |
415 | |
531 | |
416 | =item aio_link $srcpath, $dstpath, $callback->($status) |
532 | =item aio_link $srcpath, $dstpath, $callback->($status) |
417 | |
533 | |
418 | Asynchronously create a new link to the existing object at C<$srcpath> at |
534 | Asynchronously create a new link to the existing object at C<$srcpath> at |
419 | the path C<$dstpath> and call the callback with the result code. |
535 | the path C<$dstpath> and call the callback with the result code. |
420 | |
536 | |
|
|
537 | |
421 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
538 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
422 | |
539 | |
423 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
540 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
424 | the path C<$dstpath> and call the callback with the result code. |
541 | the path C<$dstpath> and call the callback with the result code. |
|
|
542 | |
425 | |
543 | |
426 | =item aio_readlink $path, $callback->($link) |
544 | =item aio_readlink $path, $callback->($link) |
427 | |
545 | |
428 | Asynchronously read the symlink specified by C<$path> and pass it to |
546 | Asynchronously read the symlink specified by C<$path> and pass it to |
429 | the callback. If an error occurs, nothing or undef gets passed to the |
547 | the callback. If an error occurs, nothing or undef gets passed to the |
430 | callback. |
548 | callback. |
431 | |
549 | |
|
|
550 | |
432 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
551 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
433 | |
552 | |
434 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
553 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
435 | rename(2) and call the callback with the result code. |
554 | rename(2) and call the callback with the result code. |
|
|
555 | |
436 | |
556 | |
437 | =item aio_mkdir $pathname, $mode, $callback->($status) |
557 | =item aio_mkdir $pathname, $mode, $callback->($status) |
438 | |
558 | |
439 | Asynchronously mkdir (create) a directory and call the callback with |
559 | Asynchronously mkdir (create) a directory and call the callback with |
440 | the result code. C<$mode> will be modified by the umask at the time the |
560 | the result code. C<$mode> will be modified by the umask at the time the |
441 | request is executed, so do not change your umask. |
561 | request is executed, so do not change your umask. |
442 | |
562 | |
|
|
563 | |
443 | =item aio_rmdir $pathname, $callback->($status) |
564 | =item aio_rmdir $pathname, $callback->($status) |
444 | |
565 | |
445 | Asynchronously rmdir (delete) a directory and call the callback with the |
566 | Asynchronously rmdir (delete) a directory and call the callback with the |
446 | result code. |
567 | result code. |
|
|
568 | |
447 | |
569 | |
448 | =item aio_readdir $pathname, $callback->($entries) |
570 | =item aio_readdir $pathname, $callback->($entries) |
449 | |
571 | |
450 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
572 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
451 | directory (i.e. opendir + readdir + closedir). The entries will not be |
573 | directory (i.e. opendir + readdir + closedir). The entries will not be |
452 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
574 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
453 | |
575 | |
454 | The callback a single argument which is either C<undef> or an array-ref |
576 | The callback a single argument which is either C<undef> or an array-ref |
455 | with the filenames. |
577 | with the filenames. |
|
|
578 | |
456 | |
579 | |
457 | =item aio_load $path, $data, $callback->($status) |
580 | =item aio_load $path, $data, $callback->($status) |
458 | |
581 | |
459 | This is a composite request that tries to fully load the given file into |
582 | This is a composite request that tries to fully load the given file into |
460 | memory. Status is the same as with aio_read. |
583 | memory. Status is the same as with aio_read. |
… | |
… | |
1140 | This is a very bad function to use in interactive programs because it |
1263 | This is a very bad function to use in interactive programs because it |
1141 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1264 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1142 | use an C<aio_group> together with a feed callback. |
1265 | use an C<aio_group> together with a feed callback. |
1143 | |
1266 | |
1144 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
1267 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
1145 | to queue up more than this number of requests, the next call to the |
1268 | do queue up more than this number of requests, the next call to the |
1146 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
1269 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
1147 | function will block until the limit is no longer exceeded. |
1270 | function will block until the limit is no longer exceeded. |
1148 | |
1271 | |
1149 | The default value is very large, so there is no practical limit on the |
1272 | The default value is very large, so there is no practical limit on the |
1150 | number of outstanding requests. |
1273 | number of outstanding requests. |
… | |
… | |
1180 | but not yet processed by poll_cb). |
1303 | but not yet processed by poll_cb). |
1181 | |
1304 | |
1182 | =back |
1305 | =back |
1183 | |
1306 | |
1184 | =cut |
1307 | =cut |
1185 | |
|
|
1186 | # support function to convert a fd into a perl filehandle |
|
|
1187 | sub _fd2fh { |
|
|
1188 | return undef if $_[0] < 0; |
|
|
1189 | |
|
|
1190 | # try to generate nice filehandles |
|
|
1191 | my $sym = "IO::AIO::fd#$_[0]"; |
|
|
1192 | local *$sym; |
|
|
1193 | |
|
|
1194 | open *$sym, "+<&=$_[0]" # usually works under any unix |
|
|
1195 | or open *$sym, "<&=$_[0]" # cygwin needs this |
|
|
1196 | or open *$sym, ">&=$_[0]" # or this |
|
|
1197 | or return undef; |
|
|
1198 | |
|
|
1199 | *$sym |
|
|
1200 | } |
|
|
1201 | |
1308 | |
1202 | min_parallel 8; |
1309 | min_parallel 8; |
1203 | |
1310 | |
1204 | END { flush } |
1311 | END { flush } |
1205 | |
1312 | |
… | |
… | |
1229 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
1336 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
1230 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
1337 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
1231 | scalars and other data passed into aio requests will also be locked and |
1338 | scalars and other data passed into aio requests will also be locked and |
1232 | will consume memory till the request has entered the done state. |
1339 | will consume memory till the request has entered the done state. |
1233 | |
1340 | |
1234 | This is now awfully much, so queuing lots of requests is not usually a |
1341 | This is not awfully much, so queuing lots of requests is not usually a |
1235 | problem. |
1342 | problem. |
1236 | |
1343 | |
1237 | Per-thread usage: |
1344 | Per-thread usage: |
1238 | |
1345 | |
1239 | In the execution phase, some aio requests require more memory for |
1346 | In the execution phase, some aio requests require more memory for |