… | |
… | |
5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
6 | |
6 | |
7 | use IO::AIO; |
7 | use IO::AIO; |
8 | |
8 | |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
10 | my ($fh) = @_; |
10 | my $fh = shift |
|
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11 | or die "/etc/passwd: $!"; |
11 | ... |
12 | ... |
12 | }; |
13 | }; |
13 | |
14 | |
14 | aio_unlink "/tmp/file", sub { }; |
15 | aio_unlink "/tmp/file", sub { }; |
15 | |
16 | |
… | |
… | |
50 | |
51 | |
51 | =head1 DESCRIPTION |
52 | =head1 DESCRIPTION |
52 | |
53 | |
53 | This module implements asynchronous I/O using whatever means your |
54 | This module implements asynchronous I/O using whatever means your |
54 | operating system supports. |
55 | operating system supports. |
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56 | |
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57 | Asynchronous means that operations that can normally block your program |
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58 | (e.g. reading from disk) will be done asynchronously: the operation |
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59 | will still block, but you can do something else in the meantime. This |
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60 | is extremely useful for programs that need to stay interactive even |
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61 | when doing heavy I/O (GUI programs, high performance network servers |
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62 | etc.), but can also be used to easily do operations in parallel that are |
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63 | normally done sequentially, e.g. stat'ing many files, which is much faster |
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64 | on a RAID volume or over NFS when you do a number of stat operations |
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65 | concurrently. |
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66 | |
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67 | While most of this works on all types of file descriptors (for example |
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68 | sockets), using these functions on file descriptors that support |
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69 | nonblocking operation (again, sockets, pipes etc.) is very inefficient or |
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70 | might not work (aio_read fails on sockets/pipes/fifos). Use an event loop |
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71 | for that (such as the L<Event|Event> module): IO::AIO will naturally fit |
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72 | into such an event loop itself. |
55 | |
73 | |
56 | In this version, a number of threads are started that execute your |
74 | In this version, a number of threads are started that execute your |
57 | requests and signal their completion. You don't need thread support |
75 | requests and signal their completion. You don't need thread support |
58 | in perl, and the threads created by this module will not be visible |
76 | in perl, and the threads created by this module will not be visible |
59 | to perl. In the future, this module might make use of the native aio |
77 | to perl. In the future, this module might make use of the native aio |
60 | functions available on many operating systems. However, they are often |
78 | functions available on many operating systems. However, they are often |
61 | not well-supported or restricted (Linux doesn't allow them on normal |
79 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
62 | files currently, for example), and they would only support aio_read and |
80 | files currently, for example), and they would only support aio_read and |
63 | aio_write, so the remaining functionality would have to be implemented |
81 | aio_write, so the remaining functionality would have to be implemented |
64 | using threads anyway. |
82 | using threads anyway. |
65 | |
83 | |
66 | Although the module will work with in the presence of other (Perl-) |
84 | Although the module will work with in the presence of other (Perl-) |
67 | threads, it is currently not reentrant in any way, so use appropriate |
85 | threads, it is currently not reentrant in any way, so use appropriate |
68 | locking yourself, always call C<poll_cb> from within the same thread, or |
86 | locking yourself, always call C<poll_cb> from within the same thread, or |
69 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
87 | never call C<poll_cb> (or other C<aio_> functions) recursively. |
70 | |
88 | |
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89 | =head2 EXAMPLE |
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90 | |
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91 | This is a simple example that uses the Event module and loads |
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92 | F</etc/passwd> asynchronously: |
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93 | |
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94 | use Fcntl; |
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95 | use Event; |
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96 | use IO::AIO; |
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97 | |
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98 | # register the IO::AIO callback with Event |
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99 | Event->io (fd => IO::AIO::poll_fileno, |
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100 | poll => 'r', |
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101 | cb => \&IO::AIO::poll_cb); |
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102 | |
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103 | # queue the request to open /etc/passwd |
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104 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
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105 | my $fh = shift |
|
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106 | or die "error while opening: $!"; |
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107 | |
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108 | # stat'ing filehandles is generally non-blocking |
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109 | my $size = -s $fh; |
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110 | |
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111 | # queue a request to read the file |
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112 | my $contents; |
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113 | aio_read $fh, 0, $size, $contents, 0, sub { |
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114 | $_[0] == $size |
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115 | or die "short read: $!"; |
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116 | |
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117 | close $fh; |
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118 | |
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119 | # file contents now in $contents |
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120 | print $contents; |
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121 | |
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122 | # exit event loop and program |
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123 | Event::unloop; |
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124 | }; |
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125 | }; |
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126 | |
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127 | # possibly queue up other requests, or open GUI windows, |
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128 | # check for sockets etc. etc. |
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129 | |
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130 | # process events as long as there are some: |
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131 | Event::loop; |
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132 | |
71 | =head1 REQUEST ANATOMY AND LIFETIME |
133 | =head1 REQUEST ANATOMY AND LIFETIME |
72 | |
134 | |
73 | 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 |
74 | directly visible to Perl. |
136 | directly visible to Perl. |
75 | |
137 | |
… | |
… | |
116 | Request has reached the end of its lifetime and holds no resources anymore |
178 | Request has reached the end of its lifetime and holds no resources anymore |
117 | (except possibly for the Perl object, but its connection to the actual |
179 | (except possibly for the Perl object, but its connection to the actual |
118 | aio request is severed and calling its methods will either do nothing or |
180 | aio request is severed and calling its methods will either do nothing or |
119 | result in a runtime error). |
181 | result in a runtime error). |
120 | |
182 | |
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183 | =back |
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184 | |
121 | =cut |
185 | =cut |
122 | |
186 | |
123 | package IO::AIO; |
187 | package IO::AIO; |
124 | |
188 | |
125 | no warnings; |
189 | no warnings; |
126 | use strict 'vars'; |
190 | use strict 'vars'; |
127 | |
191 | |
128 | use base 'Exporter'; |
192 | use base 'Exporter'; |
129 | |
193 | |
130 | BEGIN { |
194 | BEGIN { |
131 | our $VERSION = '2.0'; |
195 | our $VERSION = '2.31'; |
132 | |
196 | |
133 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
197 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
134 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
198 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
135 | aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move |
199 | aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link |
136 | aio_copy aio_group aio_nop aio_mknod); |
200 | aio_move aio_copy aio_group aio_nop aio_mknod aio_load); |
137 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
201 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); |
138 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
202 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
139 | min_parallel max_parallel nreqs nready npending); |
203 | min_parallel max_parallel max_idle |
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204 | nreqs nready npending nthreads |
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205 | max_poll_time max_poll_reqs); |
140 | |
206 | |
141 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
207 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
142 | |
208 | |
143 | require XSLoader; |
209 | require XSLoader; |
144 | XSLoader::load ("IO::AIO", $VERSION); |
210 | XSLoader::load ("IO::AIO", $VERSION); |
145 | } |
211 | } |
146 | |
212 | |
147 | =head1 FUNCTIONS |
213 | =head1 FUNCTIONS |
148 | |
214 | |
149 | =head2 AIO FUNCTIONS |
215 | =head2 AIO REQUEST FUNCTIONS |
150 | |
216 | |
151 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
217 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
152 | with the same name (sans C<aio_>). The arguments are similar or identical, |
218 | with the same name (sans C<aio_>). The arguments are similar or identical, |
153 | and they all accept an additional (and optional) C<$callback> argument |
219 | and they all accept an additional (and optional) C<$callback> argument |
154 | which must be a code reference. This code reference will get called with |
220 | which must be a code reference. This code reference will get called with |
… | |
… | |
157 | syscall has been executed asynchronously. |
223 | syscall has been executed asynchronously. |
158 | |
224 | |
159 | All functions expecting a filehandle keep a copy of the filehandle |
225 | All functions expecting a filehandle keep a copy of the filehandle |
160 | internally until the request has finished. |
226 | internally until the request has finished. |
161 | |
227 | |
162 | All requests return objects of type L<IO::AIO::REQ> that allow further |
228 | All functions return request objects of type L<IO::AIO::REQ> that allow |
163 | manipulation of those requests while they are in-flight. |
229 | further manipulation of those requests while they are in-flight. |
164 | |
230 | |
165 | The pathnames you pass to these routines I<must> be absolute and |
231 | The pathnames you pass to these routines I<must> be absolute and |
166 | encoded in byte form. The reason for the former is that at the time the |
232 | encoded as octets. The reason for the former is that at the time the |
167 | request is being executed, the current working directory could have |
233 | request is being executed, the current working directory could have |
168 | changed. Alternatively, you can make sure that you never change the |
234 | changed. Alternatively, you can make sure that you never change the |
169 | current working directory. |
235 | current working directory anywhere in the program and then use relative |
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236 | paths. |
170 | |
237 | |
171 | To encode pathnames to byte form, either make sure you either: a) |
238 | To encode pathnames as octets, either make sure you either: a) always pass |
172 | always pass in filenames you got from outside (command line, readdir |
239 | in filenames you got from outside (command line, readdir etc.) without |
173 | etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
240 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
174 | your pathnames to the locale (or other) encoding in effect in the user |
241 | your pathnames to the locale (or other) encoding in effect in the user |
175 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
242 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
176 | use something else. |
243 | use something else to ensure your scalar has the correct contents. |
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244 | |
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245 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
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246 | handles correctly wether it is set or not. |
177 | |
247 | |
178 | =over 4 |
248 | =over 4 |
179 | |
249 | |
180 | =item $prev_pri = aioreq_pri [$pri] |
250 | =item $prev_pri = aioreq_pri [$pri] |
181 | |
251 | |
… | |
… | |
204 | }; |
274 | }; |
205 | |
275 | |
206 | =item aioreq_nice $pri_adjust |
276 | =item aioreq_nice $pri_adjust |
207 | |
277 | |
208 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
278 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
209 | priority, so effects are cumulative. |
279 | priority, so the effect is cumulative. |
210 | |
280 | |
211 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
281 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
212 | |
282 | |
213 | Asynchronously open or create a file and call the callback with a newly |
283 | Asynchronously open or create a file and call the callback with a newly |
214 | created filehandle for the file. |
284 | created filehandle for the file. |
… | |
… | |
331 | Asynchronously unlink (delete) a file and call the callback with the |
401 | Asynchronously unlink (delete) a file and call the callback with the |
332 | result code. |
402 | result code. |
333 | |
403 | |
334 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
404 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
335 | |
405 | |
|
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406 | [EXPERIMENTAL] |
|
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407 | |
336 | Asynchronously create a device node (or fifo). See mknod(2): the only |
408 | Asynchronously create a device node (or fifo). See mknod(2). |
337 | portable value for C<$mode> is C<S_IFIFO> ored with permissions, and C<0> |
409 | |
338 | for C<$dev>. |
410 | The only (POSIX-) portable way of calling this function is: |
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411 | |
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412 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
339 | |
413 | |
340 | =item aio_link $srcpath, $dstpath, $callback->($status) |
414 | =item aio_link $srcpath, $dstpath, $callback->($status) |
341 | |
415 | |
342 | Asynchronously create a new link to the existing object at C<$srcpath> at |
416 | Asynchronously create a new link to the existing object at C<$srcpath> at |
343 | the path C<$dstpath> and call the callback with the result code. |
417 | the path C<$dstpath> and call the callback with the result code. |
344 | |
418 | |
345 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
419 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
346 | |
420 | |
347 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
421 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
348 | the path C<$dstpath> and call the callback with the result code. |
422 | the path C<$dstpath> and call the callback with the result code. |
|
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423 | |
|
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424 | =item aio_readlink $path, $callback->($link) |
|
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425 | |
|
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426 | Asynchronously read the symlink specified by C<$path> and pass it to |
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427 | the callback. If an error occurs, nothing or undef gets passed to the |
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428 | callback. |
349 | |
429 | |
350 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
430 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
351 | |
431 | |
352 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
432 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
353 | rename(2) and call the callback with the result code. |
433 | rename(2) and call the callback with the result code. |
… | |
… | |
363 | directory (i.e. opendir + readdir + closedir). The entries will not be |
443 | directory (i.e. opendir + readdir + closedir). The entries will not be |
364 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
444 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
365 | |
445 | |
366 | The callback a single argument which is either C<undef> or an array-ref |
446 | The callback a single argument which is either C<undef> or an array-ref |
367 | with the filenames. |
447 | with the filenames. |
|
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448 | |
|
|
449 | =item aio_load $path, $data, $callback->($status) |
|
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450 | |
|
|
451 | This is a composite request that tries to fully load the given file into |
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452 | memory. Status is the same as with aio_read. |
|
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453 | |
|
|
454 | =cut |
|
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455 | |
|
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456 | sub aio_load($$;$) { |
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457 | aio_block { |
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458 | my ($path, undef, $cb) = @_; |
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459 | my $data = \$_[1]; |
|
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460 | |
|
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461 | my $pri = aioreq_pri; |
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462 | my $grp = aio_group $cb; |
|
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463 | |
|
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464 | aioreq_pri $pri; |
|
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465 | add $grp aio_open $path, O_RDONLY, 0, sub { |
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466 | my ($fh) = @_ |
|
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467 | or return $grp->result (-1); |
|
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468 | |
|
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469 | aioreq_pri $pri; |
|
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470 | add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub { |
|
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471 | $grp->result ($_[0]); |
|
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472 | }; |
|
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473 | }; |
|
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474 | |
|
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475 | $grp |
|
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476 | } |
|
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477 | } |
368 | |
478 | |
369 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
479 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
370 | |
480 | |
371 | Try to copy the I<file> (directories not supported as either source or |
481 | Try to copy the I<file> (directories not supported as either source or |
372 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
482 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
… | |
… | |
382 | errors are being ignored. |
492 | errors are being ignored. |
383 | |
493 | |
384 | =cut |
494 | =cut |
385 | |
495 | |
386 | sub aio_copy($$;$) { |
496 | sub aio_copy($$;$) { |
|
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497 | aio_block { |
387 | my ($src, $dst, $cb) = @_; |
498 | my ($src, $dst, $cb) = @_; |
388 | |
499 | |
389 | my $pri = aioreq_pri; |
500 | my $pri = aioreq_pri; |
390 | my $grp = aio_group $cb; |
501 | my $grp = aio_group $cb; |
391 | |
502 | |
392 | aioreq_pri $pri; |
503 | aioreq_pri $pri; |
393 | add $grp aio_open $src, O_RDONLY, 0, sub { |
504 | add $grp aio_open $src, O_RDONLY, 0, sub { |
394 | if (my $src_fh = $_[0]) { |
505 | if (my $src_fh = $_[0]) { |
395 | my @stat = stat $src_fh; |
506 | my @stat = stat $src_fh; |
396 | |
507 | |
397 | aioreq_pri $pri; |
508 | aioreq_pri $pri; |
398 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
509 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
399 | if (my $dst_fh = $_[0]) { |
510 | if (my $dst_fh = $_[0]) { |
400 | aioreq_pri $pri; |
511 | aioreq_pri $pri; |
401 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
512 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
402 | if ($_[0] == $stat[7]) { |
513 | if ($_[0] == $stat[7]) { |
403 | $grp->result (0); |
514 | $grp->result (0); |
404 | close $src_fh; |
515 | close $src_fh; |
405 | |
516 | |
406 | # those should not normally block. should. should. |
517 | # those should not normally block. should. should. |
407 | utime $stat[8], $stat[9], $dst; |
518 | utime $stat[8], $stat[9], $dst; |
408 | chmod $stat[2] & 07777, $dst_fh; |
519 | chmod $stat[2] & 07777, $dst_fh; |
409 | chown $stat[4], $stat[5], $dst_fh; |
520 | chown $stat[4], $stat[5], $dst_fh; |
410 | close $dst_fh; |
521 | close $dst_fh; |
411 | } else { |
522 | } else { |
412 | $grp->result (-1); |
523 | $grp->result (-1); |
413 | close $src_fh; |
524 | close $src_fh; |
414 | close $dst_fh; |
525 | close $dst_fh; |
415 | |
526 | |
416 | aioreq $pri; |
527 | aioreq $pri; |
417 | add $grp aio_unlink $dst; |
528 | add $grp aio_unlink $dst; |
|
|
529 | } |
418 | } |
530 | }; |
|
|
531 | } else { |
|
|
532 | $grp->result (-1); |
419 | }; |
533 | } |
420 | } else { |
|
|
421 | $grp->result (-1); |
|
|
422 | } |
534 | }, |
|
|
535 | |
|
|
536 | } else { |
|
|
537 | $grp->result (-1); |
423 | }, |
538 | } |
424 | |
|
|
425 | } else { |
|
|
426 | $grp->result (-1); |
|
|
427 | } |
539 | }; |
|
|
540 | |
|
|
541 | $grp |
428 | }; |
542 | } |
429 | |
|
|
430 | $grp |
|
|
431 | } |
543 | } |
432 | |
544 | |
433 | =item aio_move $srcpath, $dstpath, $callback->($status) |
545 | =item aio_move $srcpath, $dstpath, $callback->($status) |
434 | |
546 | |
435 | Try to move the I<file> (directories not supported as either source or |
547 | Try to move the I<file> (directories not supported as either source or |
… | |
… | |
441 | that is successful, unlinking the C<$srcpath>. |
553 | that is successful, unlinking the C<$srcpath>. |
442 | |
554 | |
443 | =cut |
555 | =cut |
444 | |
556 | |
445 | sub aio_move($$;$) { |
557 | sub aio_move($$;$) { |
|
|
558 | aio_block { |
446 | my ($src, $dst, $cb) = @_; |
559 | my ($src, $dst, $cb) = @_; |
447 | |
560 | |
448 | my $pri = aioreq_pri; |
561 | my $pri = aioreq_pri; |
449 | my $grp = aio_group $cb; |
562 | my $grp = aio_group $cb; |
450 | |
563 | |
451 | aioreq_pri $pri; |
564 | aioreq_pri $pri; |
452 | add $grp aio_rename $src, $dst, sub { |
565 | add $grp aio_rename $src, $dst, sub { |
453 | if ($_[0] && $! == EXDEV) { |
566 | if ($_[0] && $! == EXDEV) { |
454 | aioreq_pri $pri; |
567 | aioreq_pri $pri; |
455 | add $grp aio_copy $src, $dst, sub { |
568 | add $grp aio_copy $src, $dst, sub { |
|
|
569 | $grp->result ($_[0]); |
|
|
570 | |
|
|
571 | if (!$_[0]) { |
|
|
572 | aioreq_pri $pri; |
|
|
573 | add $grp aio_unlink $src; |
|
|
574 | } |
|
|
575 | }; |
|
|
576 | } else { |
456 | $grp->result ($_[0]); |
577 | $grp->result ($_[0]); |
457 | |
|
|
458 | if (!$_[0]) { |
|
|
459 | aioreq_pri $pri; |
|
|
460 | add $grp aio_unlink $src; |
|
|
461 | } |
|
|
462 | }; |
578 | } |
463 | } else { |
|
|
464 | $grp->result ($_[0]); |
|
|
465 | } |
579 | }; |
|
|
580 | |
|
|
581 | $grp |
466 | }; |
582 | } |
467 | |
|
|
468 | $grp |
|
|
469 | } |
583 | } |
470 | |
584 | |
471 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
585 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
472 | |
586 | |
473 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
587 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
… | |
… | |
521 | directory counting heuristic. |
635 | directory counting heuristic. |
522 | |
636 | |
523 | =cut |
637 | =cut |
524 | |
638 | |
525 | sub aio_scandir($$$) { |
639 | sub aio_scandir($$$) { |
|
|
640 | aio_block { |
526 | my ($path, $maxreq, $cb) = @_; |
641 | my ($path, $maxreq, $cb) = @_; |
527 | |
642 | |
528 | my $pri = aioreq_pri; |
643 | my $pri = aioreq_pri; |
529 | |
644 | |
530 | my $grp = aio_group $cb; |
645 | my $grp = aio_group $cb; |
531 | |
646 | |
532 | $maxreq = 4 if $maxreq <= 0; |
647 | $maxreq = 4 if $maxreq <= 0; |
533 | |
648 | |
534 | # stat once |
649 | # stat once |
535 | aioreq_pri $pri; |
|
|
536 | add $grp aio_stat $path, sub { |
|
|
537 | return $grp->result () if $_[0]; |
|
|
538 | my $now = time; |
|
|
539 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
540 | |
|
|
541 | # read the directory entries |
|
|
542 | aioreq_pri $pri; |
650 | aioreq_pri $pri; |
543 | add $grp aio_readdir $path, sub { |
651 | add $grp aio_stat $path, sub { |
544 | my $entries = shift |
|
|
545 | or return $grp->result (); |
652 | return $grp->result () if $_[0]; |
|
|
653 | my $now = time; |
|
|
654 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
546 | |
655 | |
547 | # stat the dir another time |
656 | # read the directory entries |
548 | aioreq_pri $pri; |
657 | aioreq_pri $pri; |
|
|
658 | add $grp aio_readdir $path, sub { |
|
|
659 | my $entries = shift |
|
|
660 | or return $grp->result (); |
|
|
661 | |
|
|
662 | # stat the dir another time |
|
|
663 | aioreq_pri $pri; |
549 | add $grp aio_stat $path, sub { |
664 | add $grp aio_stat $path, sub { |
550 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
665 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
551 | |
666 | |
552 | my $ndirs; |
667 | my $ndirs; |
553 | |
668 | |
554 | # take the slow route if anything looks fishy |
669 | # take the slow route if anything looks fishy |
555 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
670 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
556 | $ndirs = -1; |
671 | $ndirs = -1; |
557 | } else { |
672 | } else { |
558 | # if nlink == 2, we are finished |
673 | # if nlink == 2, we are finished |
559 | # on non-posix-fs's, we rely on nlink < 2 |
674 | # on non-posix-fs's, we rely on nlink < 2 |
560 | $ndirs = (stat _)[3] - 2 |
675 | $ndirs = (stat _)[3] - 2 |
561 | or return $grp->result ([], $entries); |
676 | or return $grp->result ([], $entries); |
562 | } |
677 | } |
563 | |
678 | |
564 | # sort into likely dirs and likely nondirs |
679 | # sort into likely dirs and likely nondirs |
565 | # dirs == files without ".", short entries first |
680 | # dirs == files without ".", short entries first |
566 | $entries = [map $_->[0], |
681 | $entries = [map $_->[0], |
567 | sort { $b->[1] cmp $a->[1] } |
682 | sort { $b->[1] cmp $a->[1] } |
568 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
683 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
569 | @$entries]; |
684 | @$entries]; |
570 | |
685 | |
571 | my (@dirs, @nondirs); |
686 | my (@dirs, @nondirs); |
572 | |
687 | |
573 | my $statgrp = add $grp aio_group sub { |
688 | my $statgrp = add $grp aio_group sub { |
574 | $grp->result (\@dirs, \@nondirs); |
689 | $grp->result (\@dirs, \@nondirs); |
575 | }; |
690 | }; |
576 | |
691 | |
577 | limit $statgrp $maxreq; |
692 | limit $statgrp $maxreq; |
578 | feed $statgrp sub { |
693 | feed $statgrp sub { |
579 | return unless @$entries; |
694 | return unless @$entries; |
580 | my $entry = pop @$entries; |
695 | my $entry = pop @$entries; |
581 | |
696 | |
582 | aioreq_pri $pri; |
697 | aioreq_pri $pri; |
583 | add $statgrp aio_stat "$path/$entry/.", sub { |
698 | add $statgrp aio_stat "$path/$entry/.", sub { |
584 | if ($_[0] < 0) { |
699 | if ($_[0] < 0) { |
585 | push @nondirs, $entry; |
700 | push @nondirs, $entry; |
586 | } else { |
701 | } else { |
587 | # need to check for real directory |
702 | # need to check for real directory |
588 | aioreq_pri $pri; |
703 | aioreq_pri $pri; |
589 | add $statgrp aio_lstat "$path/$entry", sub { |
704 | add $statgrp aio_lstat "$path/$entry", sub { |
590 | if (-d _) { |
705 | if (-d _) { |
591 | push @dirs, $entry; |
706 | push @dirs, $entry; |
592 | |
707 | |
593 | unless (--$ndirs) { |
708 | unless (--$ndirs) { |
594 | push @nondirs, @$entries; |
709 | push @nondirs, @$entries; |
595 | feed $statgrp; |
710 | feed $statgrp; |
|
|
711 | } |
|
|
712 | } else { |
|
|
713 | push @nondirs, $entry; |
596 | } |
714 | } |
597 | } else { |
|
|
598 | push @nondirs, $entry; |
|
|
599 | } |
715 | } |
600 | } |
716 | } |
601 | } |
717 | }; |
602 | }; |
718 | }; |
603 | }; |
719 | }; |
604 | }; |
720 | }; |
605 | }; |
721 | }; |
|
|
722 | |
|
|
723 | $grp |
606 | }; |
724 | } |
607 | |
|
|
608 | $grp |
|
|
609 | } |
725 | } |
610 | |
726 | |
611 | =item aio_fsync $fh, $callback->($status) |
727 | =item aio_fsync $fh, $callback->($status) |
612 | |
728 | |
613 | Asynchronously call fsync on the given filehandle and call the callback |
729 | Asynchronously call fsync on the given filehandle and call the callback |
… | |
… | |
827 | |
943 | |
828 | =back |
944 | =back |
829 | |
945 | |
830 | =head2 SUPPORT FUNCTIONS |
946 | =head2 SUPPORT FUNCTIONS |
831 | |
947 | |
|
|
948 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
|
|
949 | |
832 | =over 4 |
950 | =over 4 |
833 | |
951 | |
834 | =item $fileno = IO::AIO::poll_fileno |
952 | =item $fileno = IO::AIO::poll_fileno |
835 | |
953 | |
836 | Return the I<request result pipe file descriptor>. This filehandle must be |
954 | Return the I<request result pipe file descriptor>. This filehandle must be |
… | |
… | |
840 | |
958 | |
841 | See C<poll_cb> for an example. |
959 | See C<poll_cb> for an example. |
842 | |
960 | |
843 | =item IO::AIO::poll_cb |
961 | =item IO::AIO::poll_cb |
844 | |
962 | |
845 | Process all outstanding events on the result pipe. You have to call this |
963 | Process some outstanding events on the result pipe. You have to call this |
846 | regularly. Returns the number of events processed. Returns immediately |
964 | regularly. Returns the number of events processed. Returns immediately |
847 | when no events are outstanding. |
965 | when no events are outstanding. The amount of events processed depends on |
|
|
966 | the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
848 | |
967 | |
849 | If not all requests were processed for whatever reason, the filehandle |
968 | If not all requests were processed for whatever reason, the filehandle |
850 | will still be ready when C<poll_cb> returns. |
969 | will still be ready when C<poll_cb> returns. |
851 | |
970 | |
852 | Example: Install an Event watcher that automatically calls |
971 | Example: Install an Event watcher that automatically calls |
… | |
… | |
854 | |
973 | |
855 | Event->io (fd => IO::AIO::poll_fileno, |
974 | Event->io (fd => IO::AIO::poll_fileno, |
856 | poll => 'r', async => 1, |
975 | poll => 'r', async => 1, |
857 | cb => \&IO::AIO::poll_cb); |
976 | cb => \&IO::AIO::poll_cb); |
858 | |
977 | |
859 | =item IO::AIO::poll_some $max_requests |
978 | =item IO::AIO::max_poll_reqs $nreqs |
860 | |
979 | |
861 | Similar to C<poll_cb>, but only processes up to C<$max_requests> requests |
980 | =item IO::AIO::max_poll_time $seconds |
862 | at a time. |
|
|
863 | |
981 | |
864 | Useful if you want to ensure some level of interactiveness when perl is |
982 | These set the maximum number of requests (default C<0>, meaning infinity) |
865 | not fast enough to process all requests in time. |
983 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
|
|
984 | the maximum amount of time (default C<0>, meaning infinity) spent in |
|
|
985 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
|
|
986 | of time C<poll_cb> is allowed to use). |
|
|
987 | |
|
|
988 | Setting C<max_poll_time> to a non-zero value creates an overhead of one |
|
|
989 | syscall per request processed, which is not normally a problem unless your |
|
|
990 | callbacks are really really fast or your OS is really really slow (I am |
|
|
991 | not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead. |
|
|
992 | |
|
|
993 | Setting these is useful if you want to ensure some level of |
|
|
994 | interactiveness when perl is not fast enough to process all requests in |
|
|
995 | time. |
|
|
996 | |
|
|
997 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
866 | |
998 | |
867 | Example: Install an Event watcher that automatically calls |
999 | Example: Install an Event watcher that automatically calls |
868 | IO::AIO::poll_some with low priority, to ensure that other parts of the |
1000 | IO::AIO::poll_cb with low priority, to ensure that other parts of the |
869 | program get the CPU sometimes even under high AIO load. |
1001 | program get the CPU sometimes even under high AIO load. |
870 | |
1002 | |
|
|
1003 | # try not to spend much more than 0.1s in poll_cb |
|
|
1004 | IO::AIO::max_poll_time 0.1; |
|
|
1005 | |
|
|
1006 | # use a low priority so other tasks have priority |
871 | Event->io (fd => IO::AIO::poll_fileno, |
1007 | Event->io (fd => IO::AIO::poll_fileno, |
872 | poll => 'r', nice => 1, |
1008 | poll => 'r', nice => 1, |
873 | cb => sub { IO::AIO::poll_some 256 }); |
1009 | cb => &IO::AIO::poll_cb); |
874 | |
1010 | |
875 | =item IO::AIO::poll_wait |
1011 | =item IO::AIO::poll_wait |
876 | |
1012 | |
|
|
1013 | If there are any outstanding requests and none of them in the result |
877 | Wait till the result filehandle becomes ready for reading (simply does a |
1014 | phase, wait till the result filehandle becomes ready for reading (simply |
878 | C<select> on the filehandle. This is useful if you want to synchronously wait |
1015 | does a C<select> on the filehandle. This is useful if you want to |
879 | for some requests to finish). |
1016 | synchronously wait for some requests to finish). |
880 | |
1017 | |
881 | See C<nreqs> for an example. |
1018 | See C<nreqs> for an example. |
882 | |
1019 | |
|
|
1020 | =item IO::AIO::poll |
|
|
1021 | |
|
|
1022 | Waits until some requests have been handled. |
|
|
1023 | |
|
|
1024 | Returns the number of requests processed, but is otherwise strictly |
|
|
1025 | equivalent to: |
|
|
1026 | |
|
|
1027 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1028 | |
883 | =item IO::AIO::nreqs |
1029 | =item IO::AIO::flush |
884 | |
1030 | |
885 | Returns the number of requests currently in the ready, execute or pending |
1031 | Wait till all outstanding AIO requests have been handled. |
886 | states (i.e. for which their callback has not been invoked yet). |
|
|
887 | |
1032 | |
888 | Example: wait till there are no outstanding requests anymore: |
1033 | Strictly equivalent to: |
889 | |
1034 | |
890 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1035 | IO::AIO::poll_wait, IO::AIO::poll_cb |
891 | while IO::AIO::nreqs; |
1036 | while IO::AIO::nreqs; |
892 | |
1037 | |
893 | =item IO::AIO::nready |
1038 | =head3 CONTROLLING THE NUMBER OF THREADS |
894 | |
|
|
895 | Returns the number of requests currently in the ready state (not yet |
|
|
896 | executed). |
|
|
897 | |
|
|
898 | =item IO::AIO::npending |
|
|
899 | |
|
|
900 | Returns the number of requests currently in the pending state (executed, |
|
|
901 | but not yet processed by poll_cb). |
|
|
902 | |
|
|
903 | =item IO::AIO::flush |
|
|
904 | |
|
|
905 | Wait till all outstanding AIO requests have been handled. |
|
|
906 | |
|
|
907 | Strictly equivalent to: |
|
|
908 | |
|
|
909 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
910 | while IO::AIO::nreqs; |
|
|
911 | |
|
|
912 | =item IO::AIO::poll |
|
|
913 | |
|
|
914 | Waits until some requests have been handled. |
|
|
915 | |
|
|
916 | Strictly equivalent to: |
|
|
917 | |
|
|
918 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
919 | if IO::AIO::nreqs; |
|
|
920 | |
1039 | |
921 | =item IO::AIO::min_parallel $nthreads |
1040 | =item IO::AIO::min_parallel $nthreads |
922 | |
1041 | |
923 | Set the minimum number of AIO threads to C<$nthreads>. The current |
1042 | Set the minimum number of AIO threads to C<$nthreads>. The current |
924 | default is C<8>, which means eight asynchronous operations can execute |
1043 | default is C<8>, which means eight asynchronous operations can execute |
925 | concurrently at any one time (the number of outstanding requests, |
1044 | concurrently at any one time (the number of outstanding requests, |
926 | however, is unlimited). |
1045 | however, is unlimited). |
927 | |
1046 | |
928 | IO::AIO starts threads only on demand, when an AIO request is queued and |
1047 | IO::AIO starts threads only on demand, when an AIO request is queued and |
929 | no free thread exists. |
1048 | no free thread exists. Please note that queueing up a hundred requests can |
|
|
1049 | create demand for a hundred threads, even if it turns out that everything |
|
|
1050 | is in the cache and could have been processed faster by a single thread. |
930 | |
1051 | |
931 | It is recommended to keep the number of threads relatively low, as some |
1052 | It is recommended to keep the number of threads relatively low, as some |
932 | Linux kernel versions will scale negatively with the number of threads |
1053 | Linux kernel versions will scale negatively with the number of threads |
933 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
1054 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
934 | versions, 4-32 threads should be fine. |
1055 | versions, 4-32 threads should be fine. |
… | |
… | |
948 | This module automatically runs C<max_parallel 0> at program end, to ensure |
1069 | This module automatically runs C<max_parallel 0> at program end, to ensure |
949 | that all threads are killed and that there are no outstanding requests. |
1070 | that all threads are killed and that there are no outstanding requests. |
950 | |
1071 | |
951 | Under normal circumstances you don't need to call this function. |
1072 | Under normal circumstances you don't need to call this function. |
952 | |
1073 | |
|
|
1074 | =item IO::AIO::max_idle $nthreads |
|
|
1075 | |
|
|
1076 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
|
|
1077 | threads that did not get a request to process within 10 seconds). That |
|
|
1078 | means if a thread becomes idle while C<$nthreads> other threads are also |
|
|
1079 | idle, it will free its resources and exit. |
|
|
1080 | |
|
|
1081 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
|
|
1082 | to allow for extremely high load situations, but want to free resources |
|
|
1083 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
|
|
1084 | |
|
|
1085 | The default is probably ok in most situations, especially if thread |
|
|
1086 | creation is fast. If thread creation is very slow on your system you might |
|
|
1087 | want to use larger values. |
|
|
1088 | |
953 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
1089 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
954 | |
1090 | |
955 | This is a very bad function to use in interactive programs because it |
1091 | This is a very bad function to use in interactive programs because it |
956 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1092 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
957 | use an C<aio_group> together with a feed callback. |
1093 | use an C<aio_group> together with a feed callback. |
… | |
… | |
966 | |
1102 | |
967 | You can still queue as many requests as you want. Therefore, |
1103 | You can still queue as many requests as you want. Therefore, |
968 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
1104 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
969 | as a stop gap to shield against fatal memory overflow (with large values). |
1105 | as a stop gap to shield against fatal memory overflow (with large values). |
970 | |
1106 | |
|
|
1107 | =head3 STATISTICAL INFORMATION |
|
|
1108 | |
|
|
1109 | =item IO::AIO::nreqs |
|
|
1110 | |
|
|
1111 | Returns the number of requests currently in the ready, execute or pending |
|
|
1112 | states (i.e. for which their callback has not been invoked yet). |
|
|
1113 | |
|
|
1114 | Example: wait till there are no outstanding requests anymore: |
|
|
1115 | |
|
|
1116 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1117 | while IO::AIO::nreqs; |
|
|
1118 | |
|
|
1119 | =item IO::AIO::nready |
|
|
1120 | |
|
|
1121 | Returns the number of requests currently in the ready state (not yet |
|
|
1122 | executed). |
|
|
1123 | |
|
|
1124 | =item IO::AIO::npending |
|
|
1125 | |
|
|
1126 | Returns the number of requests currently in the pending state (executed, |
|
|
1127 | but not yet processed by poll_cb). |
|
|
1128 | |
971 | =back |
1129 | =back |
972 | |
1130 | |
973 | =cut |
1131 | =cut |
974 | |
1132 | |
975 | # support function to convert a fd into a perl filehandle |
1133 | # support function to convert a fd into a perl filehandle |
… | |
… | |
988 | *$sym |
1146 | *$sym |
989 | } |
1147 | } |
990 | |
1148 | |
991 | min_parallel 8; |
1149 | min_parallel 8; |
992 | |
1150 | |
993 | END { |
1151 | END { flush } |
994 | flush; |
|
|
995 | }; |
|
|
996 | |
1152 | |
997 | 1; |
1153 | 1; |
998 | |
1154 | |
999 | =head2 FORK BEHAVIOUR |
1155 | =head2 FORK BEHAVIOUR |
1000 | |
1156 | |