… | |
… | |
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 |
|
|
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 | |
… | |
… | |
25 | $req->cancel; # cancel request if still in queue |
26 | $req->cancel; # cancel request if still in queue |
26 | |
27 | |
27 | my $grp = aio_group sub { print "all stats done\n" }; |
28 | my $grp = aio_group sub { print "all stats done\n" }; |
28 | add $grp aio_stat "..." for ...; |
29 | add $grp aio_stat "..." for ...; |
29 | |
30 | |
30 | # AnyEvent integration |
31 | # AnyEvent integration (EV, Event, Glib, Tk, urxvt, pureperl...) |
31 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
32 | open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; |
32 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
33 | my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); |
|
|
34 | |
|
|
35 | # EV integration |
|
|
36 | my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
33 | |
37 | |
34 | # Event integration |
38 | # Event integration |
35 | Event->io (fd => IO::AIO::poll_fileno, |
39 | Event->io (fd => IO::AIO::poll_fileno, |
36 | poll => 'r', |
40 | poll => 'r', |
37 | cb => \&IO::AIO::poll_cb); |
41 | cb => \&IO::AIO::poll_cb); |
… | |
… | |
51 | =head1 DESCRIPTION |
55 | =head1 DESCRIPTION |
52 | |
56 | |
53 | This module implements asynchronous I/O using whatever means your |
57 | This module implements asynchronous I/O using whatever means your |
54 | operating system supports. |
58 | operating system supports. |
55 | |
59 | |
|
|
60 | Asynchronous means that operations that can normally block your program |
|
|
61 | (e.g. reading from disk) will be done asynchronously: the operation |
|
|
62 | will still block, but you can do something else in the meantime. This |
|
|
63 | is extremely useful for programs that need to stay interactive even |
|
|
64 | when doing heavy I/O (GUI programs, high performance network servers |
|
|
65 | etc.), but can also be used to easily do operations in parallel that are |
|
|
66 | normally done sequentially, e.g. stat'ing many files, which is much faster |
|
|
67 | on a RAID volume or over NFS when you do a number of stat operations |
|
|
68 | concurrently. |
|
|
69 | |
|
|
70 | While most of this works on all types of file descriptors (for |
|
|
71 | example sockets), using these functions on file descriptors that |
|
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72 | support nonblocking operation (again, sockets, pipes etc.) is very |
|
|
73 | inefficient. Use an event loop for that (such as the L<Event|Event> |
|
|
74 | module): IO::AIO will naturally fit into such an event loop itself. |
|
|
75 | |
56 | Currently, a number of threads are started that execute your read/writes |
76 | In this version, a number of threads are started that execute your |
57 | and signal their completion. You don't need thread support in perl, and |
77 | requests and signal their completion. You don't need thread support |
58 | the threads created by this module will not be visible to perl. In the |
78 | in perl, and the threads created by this module will not be visible |
59 | future, this module might make use of the native aio functions available |
79 | to perl. In the future, this module might make use of the native aio |
60 | on many operating systems. However, they are often not well-supported |
80 | functions available on many operating systems. However, they are often |
61 | (Linux doesn't allow them on normal files currently, for example), |
81 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
62 | and they would only support aio_read and aio_write, so the remaining |
82 | files currently, for example), and they would only support aio_read and |
63 | functionality would have to be implemented using threads anyway. |
83 | aio_write, so the remaining functionality would have to be implemented |
|
|
84 | using threads anyway. |
64 | |
85 | |
65 | Although the module will work with in the presence of other threads, |
86 | Although the module will work in the presence of other (Perl-) threads, |
66 | it is currently not reentrant in any way, so use appropriate locking |
87 | it is currently not reentrant in any way, so use appropriate locking |
67 | yourself, always call C<poll_cb> from within the same thread, or never |
88 | yourself, always call C<poll_cb> from within the same thread, or never |
68 | call C<poll_cb> (or other C<aio_> functions) recursively. |
89 | call C<poll_cb> (or other C<aio_> functions) recursively. |
69 | |
90 | |
|
|
91 | =head2 EXAMPLE |
|
|
92 | |
|
|
93 | This is a simple example that uses the Event module and loads |
|
|
94 | F</etc/passwd> asynchronously: |
|
|
95 | |
|
|
96 | use Fcntl; |
|
|
97 | use Event; |
|
|
98 | use IO::AIO; |
|
|
99 | |
|
|
100 | # register the IO::AIO callback with Event |
|
|
101 | Event->io (fd => IO::AIO::poll_fileno, |
|
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102 | poll => 'r', |
|
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103 | cb => \&IO::AIO::poll_cb); |
|
|
104 | |
|
|
105 | # queue the request to open /etc/passwd |
|
|
106 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
|
|
107 | my $fh = shift |
|
|
108 | or die "error while opening: $!"; |
|
|
109 | |
|
|
110 | # stat'ing filehandles is generally non-blocking |
|
|
111 | my $size = -s $fh; |
|
|
112 | |
|
|
113 | # queue a request to read the file |
|
|
114 | my $contents; |
|
|
115 | aio_read $fh, 0, $size, $contents, 0, sub { |
|
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116 | $_[0] == $size |
|
|
117 | or die "short read: $!"; |
|
|
118 | |
|
|
119 | close $fh; |
|
|
120 | |
|
|
121 | # file contents now in $contents |
|
|
122 | print $contents; |
|
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123 | |
|
|
124 | # exit event loop and program |
|
|
125 | Event::unloop; |
|
|
126 | }; |
|
|
127 | }; |
|
|
128 | |
|
|
129 | # possibly queue up other requests, or open GUI windows, |
|
|
130 | # check for sockets etc. etc. |
|
|
131 | |
|
|
132 | # process events as long as there are some: |
|
|
133 | Event::loop; |
|
|
134 | |
|
|
135 | =head1 REQUEST ANATOMY AND LIFETIME |
|
|
136 | |
|
|
137 | Every C<aio_*> function creates a request. which is a C data structure not |
|
|
138 | directly visible to Perl. |
|
|
139 | |
|
|
140 | If called in non-void context, every request function returns a Perl |
|
|
141 | object representing the request. In void context, nothing is returned, |
|
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142 | which saves a bit of memory. |
|
|
143 | |
|
|
144 | The perl object is a fairly standard ref-to-hash object. The hash contents |
|
|
145 | are not used by IO::AIO so you are free to store anything you like in it. |
|
|
146 | |
|
|
147 | During their existance, aio requests travel through the following states, |
|
|
148 | in order: |
|
|
149 | |
|
|
150 | =over 4 |
|
|
151 | |
|
|
152 | =item ready |
|
|
153 | |
|
|
154 | Immediately after a request is created it is put into the ready state, |
|
|
155 | waiting for a thread to execute it. |
|
|
156 | |
|
|
157 | =item execute |
|
|
158 | |
|
|
159 | A thread has accepted the request for processing and is currently |
|
|
160 | executing it (e.g. blocking in read). |
|
|
161 | |
|
|
162 | =item pending |
|
|
163 | |
|
|
164 | The request has been executed and is waiting for result processing. |
|
|
165 | |
|
|
166 | While request submission and execution is fully asynchronous, result |
|
|
167 | processing is not and relies on the perl interpreter calling C<poll_cb> |
|
|
168 | (or another function with the same effect). |
|
|
169 | |
|
|
170 | =item result |
|
|
171 | |
|
|
172 | The request results are processed synchronously by C<poll_cb>. |
|
|
173 | |
|
|
174 | The C<poll_cb> function will process all outstanding aio requests by |
|
|
175 | calling their callbacks, freeing memory associated with them and managing |
|
|
176 | any groups they are contained in. |
|
|
177 | |
|
|
178 | =item done |
|
|
179 | |
|
|
180 | Request has reached the end of its lifetime and holds no resources anymore |
|
|
181 | (except possibly for the Perl object, but its connection to the actual |
|
|
182 | aio request is severed and calling its methods will either do nothing or |
|
|
183 | result in a runtime error). |
|
|
184 | |
|
|
185 | =back |
|
|
186 | |
70 | =cut |
187 | =cut |
71 | |
188 | |
72 | package IO::AIO; |
189 | package IO::AIO; |
|
|
190 | |
|
|
191 | use Carp (); |
73 | |
192 | |
74 | no warnings; |
193 | no warnings; |
75 | use strict 'vars'; |
194 | use strict 'vars'; |
76 | |
195 | |
77 | use base 'Exporter'; |
196 | use base 'Exporter'; |
78 | |
197 | |
79 | BEGIN { |
198 | BEGIN { |
80 | our $VERSION = '2.0'; |
199 | our $VERSION = '2.6'; |
81 | |
200 | |
82 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat |
201 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close |
83 | aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink |
202 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir |
84 | aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move |
203 | aio_scandir aio_symlink aio_readlink aio_sync aio_fsync |
85 | aio_group aio_nop); |
204 | aio_fdatasync aio_pathsync aio_readahead |
|
|
205 | aio_rename aio_link aio_move aio_copy aio_group |
|
|
206 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
|
|
207 | aio_chmod aio_utime aio_truncate); |
|
|
208 | |
86 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
209 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); |
87 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
210 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
88 | min_parallel max_parallel max_outstanding nreqs); |
211 | min_parallel max_parallel max_idle |
|
|
212 | nreqs nready npending nthreads |
|
|
213 | max_poll_time max_poll_reqs); |
89 | |
214 | |
90 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
215 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
91 | |
216 | |
92 | require XSLoader; |
217 | require XSLoader; |
93 | XSLoader::load ("IO::AIO", $VERSION); |
218 | XSLoader::load ("IO::AIO", $VERSION); |
94 | } |
219 | } |
95 | |
220 | |
96 | =head1 FUNCTIONS |
221 | =head1 FUNCTIONS |
97 | |
222 | |
98 | =head2 AIO FUNCTIONS |
223 | =head2 AIO REQUEST FUNCTIONS |
99 | |
224 | |
100 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
225 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
101 | with the same name (sans C<aio_>). The arguments are similar or identical, |
226 | with the same name (sans C<aio_>). The arguments are similar or identical, |
102 | and they all accept an additional (and optional) C<$callback> argument |
227 | and they all accept an additional (and optional) C<$callback> argument |
103 | which must be a code reference. This code reference will get called with |
228 | which must be a code reference. This code reference will get called with |
… | |
… | |
106 | syscall has been executed asynchronously. |
231 | syscall has been executed asynchronously. |
107 | |
232 | |
108 | All functions expecting a filehandle keep a copy of the filehandle |
233 | All functions expecting a filehandle keep a copy of the filehandle |
109 | internally until the request has finished. |
234 | internally until the request has finished. |
110 | |
235 | |
111 | All requests return objects of type L<IO::AIO::REQ> that allow further |
236 | All functions return request objects of type L<IO::AIO::REQ> that allow |
112 | manipulation of those requests while they are in-flight. |
237 | further manipulation of those requests while they are in-flight. |
113 | |
238 | |
114 | The pathnames you pass to these routines I<must> be absolute and |
239 | The pathnames you pass to these routines I<must> be absolute and |
115 | encoded in byte form. The reason for the former is that at the time the |
240 | encoded as octets. The reason for the former is that at the time the |
116 | request is being executed, the current working directory could have |
241 | request is being executed, the current working directory could have |
117 | changed. Alternatively, you can make sure that you never change the |
242 | changed. Alternatively, you can make sure that you never change the |
118 | current working directory. |
243 | current working directory anywhere in the program and then use relative |
|
|
244 | paths. |
119 | |
245 | |
120 | To encode pathnames to byte form, either make sure you either: a) |
246 | To encode pathnames as octets, either make sure you either: a) always pass |
121 | always pass in filenames you got from outside (command line, readdir |
247 | in filenames you got from outside (command line, readdir etc.) without |
122 | etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
248 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
123 | your pathnames to the locale (or other) encoding in effect in the user |
249 | your pathnames to the locale (or other) encoding in effect in the user |
124 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
250 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
125 | use something else. |
251 | use something else to ensure your scalar has the correct contents. |
|
|
252 | |
|
|
253 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
|
|
254 | handles correctly wether it is set or not. |
126 | |
255 | |
127 | =over 4 |
256 | =over 4 |
128 | |
257 | |
129 | =item aioreq_pri $pri |
258 | =item $prev_pri = aioreq_pri [$pri] |
130 | |
259 | |
131 | Sets the priority for the next aio request. The default priority |
260 | Returns the priority value that would be used for the next request and, if |
|
|
261 | C<$pri> is given, sets the priority for the next aio request. |
|
|
262 | |
132 | is C<0>, the minimum and maximum priorities are C<-4> and C<4>, |
263 | The default priority is C<0>, the minimum and maximum priorities are C<-4> |
133 | respectively. Requests with higher priority will be serviced first. |
264 | and C<4>, respectively. Requests with higher priority will be serviced |
|
|
265 | first. |
134 | |
266 | |
135 | The priority will be reset to C<0> after each call to one of the C<aio_> |
267 | The priority will be reset to C<0> after each call to one of the C<aio_*> |
136 | functions. |
268 | functions. |
137 | |
269 | |
138 | Example: open a file with low priority, then read something from it with |
270 | Example: open a file with low priority, then read something from it with |
139 | higher priority so the read request is serviced before other low priority |
271 | higher priority so the read request is serviced before other low priority |
140 | open requests (potentially spamming the cache): |
272 | open requests (potentially spamming the cache): |
… | |
… | |
147 | aio_read $_[0], ..., sub { |
279 | aio_read $_[0], ..., sub { |
148 | ... |
280 | ... |
149 | }; |
281 | }; |
150 | }; |
282 | }; |
151 | |
283 | |
|
|
284 | |
152 | =item aioreq_nice $pri_adjust |
285 | =item aioreq_nice $pri_adjust |
153 | |
286 | |
154 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
287 | Similar to C<aioreq_pri>, but subtracts the given value from the current |
155 | priority, so effects are cumulative. |
288 | priority, so the effect is cumulative. |
|
|
289 | |
156 | |
290 | |
157 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
291 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
158 | |
292 | |
159 | Asynchronously open or create a file and call the callback with a newly |
293 | Asynchronously open or create a file and call the callback with a newly |
160 | created filehandle for the file. |
294 | created filehandle for the file. |
… | |
… | |
166 | list. They are the same as used by C<sysopen>. |
300 | list. They are the same as used by C<sysopen>. |
167 | |
301 | |
168 | Likewise, C<$mode> specifies the mode of the newly created file, if it |
302 | Likewise, C<$mode> specifies the mode of the newly created file, if it |
169 | didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>, |
303 | didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>, |
170 | except that it is mandatory (i.e. use C<0> if you don't create new files, |
304 | except that it is mandatory (i.e. use C<0> if you don't create new files, |
171 | and C<0666> or C<0777> if you do). |
305 | and C<0666> or C<0777> if you do). Note that the C<$mode> will be modified |
|
|
306 | by the umask in effect then the request is being executed, so better never |
|
|
307 | change the umask. |
172 | |
308 | |
173 | Example: |
309 | Example: |
174 | |
310 | |
175 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
311 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
176 | if ($_[0]) { |
312 | if ($_[0]) { |
… | |
… | |
179 | } else { |
315 | } else { |
180 | die "open failed: $!\n"; |
316 | die "open failed: $!\n"; |
181 | } |
317 | } |
182 | }; |
318 | }; |
183 | |
319 | |
|
|
320 | |
184 | =item aio_close $fh, $callback->($status) |
321 | =item aio_close $fh, $callback->($status) |
185 | |
322 | |
186 | Asynchronously close a file and call the callback with the result |
323 | Asynchronously close a file and call the callback with the result |
187 | code. I<WARNING:> although accepted, you should not pass in a perl |
324 | code. |
188 | filehandle here, as perl will likely close the file descriptor another |
|
|
189 | time when the filehandle is destroyed. Normally, you can safely call perls |
|
|
190 | C<close> or just let filehandles go out of scope. |
|
|
191 | |
325 | |
192 | This is supposed to be a bug in the API, so that might change. It's |
326 | Unfortunately, you can't do this to perl. Perl I<insists> very strongly on |
193 | therefore best to avoid this function. |
327 | closing the file descriptor associated with the filehandle itself. Here is |
|
|
328 | what aio_close will try: |
|
|
329 | |
|
|
330 | 1. dup()licate the fd |
|
|
331 | 2. asynchronously close() the duplicated fd |
|
|
332 | 3. dup()licate the fd once more |
|
|
333 | 4. let perl close() the filehandle |
|
|
334 | 5. asynchronously close the duplicated fd |
|
|
335 | |
|
|
336 | The idea is that the first close() flushes stuff to disk that closing an |
|
|
337 | fd will flush, so when perl closes the fd, nothing much will need to be |
|
|
338 | flushed. The second async. close() will then flush stuff to disk that |
|
|
339 | closing the last fd to the file will flush. |
|
|
340 | |
|
|
341 | Just FYI, SuSv3 has this to say on close: |
|
|
342 | |
|
|
343 | All outstanding record locks owned by the process on the file |
|
|
344 | associated with the file descriptor shall be removed. |
|
|
345 | |
|
|
346 | If fildes refers to a socket, close() shall cause the socket to be |
|
|
347 | destroyed. ... close() shall block for up to the current linger |
|
|
348 | interval until all data is transmitted. |
|
|
349 | [this actually sounds like a specification bug, but who knows] |
|
|
350 | |
|
|
351 | And at least Linux additionally actually flushes stuff on every close, |
|
|
352 | even when the file itself is still open. |
|
|
353 | |
|
|
354 | Sounds enourmously inefficient and complicated? Yes... please show me how |
|
|
355 | to nuke perl's fd out of existence... |
|
|
356 | |
|
|
357 | =cut |
|
|
358 | |
|
|
359 | sub aio_close($;$) { |
|
|
360 | aio_block { |
|
|
361 | my ($fh, $cb) = @_; |
|
|
362 | |
|
|
363 | my $pri = aioreq_pri; |
|
|
364 | my $grp = aio_group $cb; |
|
|
365 | |
|
|
366 | my $fd = fileno $fh; |
|
|
367 | |
|
|
368 | defined $fd or Carp::croak "aio_close called with fd-less filehandle"; |
|
|
369 | |
|
|
370 | # if the dups fail we will simply get EBADF |
|
|
371 | my $fd2 = _dup $fd; |
|
|
372 | aioreq_pri $pri; |
|
|
373 | add $grp _aio_close $fd2, sub { |
|
|
374 | my $fd2 = _dup $fd; |
|
|
375 | close $fh; |
|
|
376 | aioreq_pri $pri; |
|
|
377 | add $grp _aio_close $fd2, sub { |
|
|
378 | $grp->result ($_[0]); |
|
|
379 | }; |
|
|
380 | }; |
|
|
381 | |
|
|
382 | $grp |
|
|
383 | } |
|
|
384 | } |
|
|
385 | |
194 | |
386 | |
195 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
387 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
196 | |
388 | |
197 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
389 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
198 | |
390 | |
199 | Reads or writes C<length> bytes from the specified C<fh> and C<offset> |
391 | Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset> |
200 | into the scalar given by C<data> and offset C<dataoffset> and calls the |
392 | into the scalar given by C<$data> and offset C<$dataoffset> and calls the |
201 | callback without the actual number of bytes read (or -1 on error, just |
393 | callback without the actual number of bytes read (or -1 on error, just |
202 | like the syscall). |
394 | like the syscall). |
203 | |
395 | |
|
|
396 | If C<$offset> is undefined, then the current file descriptor offset will |
|
|
397 | be used (and updated), otherwise the file descriptor offset will not be |
|
|
398 | changed by these calls. |
|
|
399 | |
|
|
400 | If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. |
|
|
401 | |
|
|
402 | If C<$dataoffset> is less than zero, it will be counted from the end of |
|
|
403 | C<$data>. |
|
|
404 | |
204 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
405 | The C<$data> scalar I<MUST NOT> be modified in any way while the request |
205 | is outstanding. Modifying it can result in segfaults or WW3 (if the |
406 | is outstanding. Modifying it can result in segfaults or World War III (if |
206 | necessary/optional hardware is installed). |
407 | the necessary/optional hardware is installed). |
207 | |
408 | |
208 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
409 | Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at |
209 | offset C<0> within the scalar: |
410 | offset C<0> within the scalar: |
210 | |
411 | |
211 | aio_read $fh, 7, 15, $buffer, 0, sub { |
412 | aio_read $fh, 7, 15, $buffer, 0, sub { |
212 | $_[0] > 0 or die "read error: $!"; |
413 | $_[0] > 0 or die "read error: $!"; |
213 | print "read $_[0] bytes: <$buffer>\n"; |
414 | print "read $_[0] bytes: <$buffer>\n"; |
214 | }; |
415 | }; |
215 | |
416 | |
216 | =item aio_move $srcpath, $dstpath, $callback->($status) |
|
|
217 | |
|
|
218 | [EXPERIMENTAL due to internal aio_group use] |
|
|
219 | |
|
|
220 | Try to move the I<file> (directories not supported as either source or |
|
|
221 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
|
|
222 | the C<0> (error) or C<-1> ok. |
|
|
223 | |
|
|
224 | This is a composite request that tries to rename(2) the file first. If |
|
|
225 | rename files with C<EXDEV>, it creates the destination file with mode 0200 |
|
|
226 | and copies the contents of the source file into it using C<aio_sendfile>, |
|
|
227 | followed by restoring atime, mtime, access mode and uid/gid, in that |
|
|
228 | order, and unlinking the C<$srcpath>. |
|
|
229 | |
|
|
230 | If an error occurs, the partial destination file will be unlinked, if |
|
|
231 | possible, except when setting atime, mtime, access mode and uid/gid, where |
|
|
232 | errors are being ignored. |
|
|
233 | |
|
|
234 | =cut |
|
|
235 | |
|
|
236 | sub aio_move($$$) { |
|
|
237 | my ($src, $dst, $cb) = @_; |
|
|
238 | |
|
|
239 | my $grp = aio_group $cb; |
|
|
240 | |
|
|
241 | add $grp aio_rename $src, $dst, sub { |
|
|
242 | if ($_[0] && $! == EXDEV) { |
|
|
243 | add $grp aio_open $src, O_RDONLY, 0, sub { |
|
|
244 | if (my $src_fh = $_[0]) { |
|
|
245 | my @stat = stat $src_fh; |
|
|
246 | |
|
|
247 | add $grp aio_open $dst, O_WRONLY, 0200, sub { |
|
|
248 | if (my $dst_fh = $_[0]) { |
|
|
249 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
|
|
250 | close $src_fh; |
|
|
251 | |
|
|
252 | if ($_[0] == $stat[7]) { |
|
|
253 | utime $stat[8], $stat[9], $dst; |
|
|
254 | chmod $stat[2] & 07777, $dst_fh; |
|
|
255 | chown $stat[4], $stat[5], $dst_fh; |
|
|
256 | close $dst_fh; |
|
|
257 | |
|
|
258 | add $grp aio_unlink $src, sub { |
|
|
259 | $grp->result ($_[0]); |
|
|
260 | }; |
|
|
261 | } else { |
|
|
262 | my $errno = $!; |
|
|
263 | add $grp aio_unlink $dst, sub { |
|
|
264 | $! = $errno; |
|
|
265 | $grp->result (-1); |
|
|
266 | }; |
|
|
267 | } |
|
|
268 | }; |
|
|
269 | } else { |
|
|
270 | $grp->result (-1); |
|
|
271 | } |
|
|
272 | }, |
|
|
273 | |
|
|
274 | } else { |
|
|
275 | $grp->result (-1); |
|
|
276 | } |
|
|
277 | }; |
|
|
278 | } else { |
|
|
279 | $grp->result ($_[0]); |
|
|
280 | } |
|
|
281 | }; |
|
|
282 | |
|
|
283 | $grp |
|
|
284 | } |
|
|
285 | |
417 | |
286 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
418 | =item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
287 | |
419 | |
288 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
420 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
289 | reading at byte offset C<$in_offset>, and starts writing at the current |
421 | reading at byte offset C<$in_offset>, and starts writing at the current |
… | |
… | |
303 | C<$in_fh> than are written, and there is no way to find out how many |
435 | C<$in_fh> than are written, and there is no way to find out how many |
304 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
436 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
305 | provides the number of bytes written to C<$out_fh>. Only if the result |
437 | provides the number of bytes written to C<$out_fh>. Only if the result |
306 | value equals C<$length> one can assume that C<$length> bytes have been |
438 | value equals C<$length> one can assume that C<$length> bytes have been |
307 | read. |
439 | read. |
|
|
440 | |
308 | |
441 | |
309 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
442 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
310 | |
443 | |
311 | C<aio_readahead> populates the page cache with data from a file so that |
444 | C<aio_readahead> populates the page cache with data from a file so that |
312 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
445 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
… | |
… | |
318 | file. The current file offset of the file is left unchanged. |
451 | file. The current file offset of the file is left unchanged. |
319 | |
452 | |
320 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
453 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
321 | emulated by simply reading the data, which would have a similar effect. |
454 | emulated by simply reading the data, which would have a similar effect. |
322 | |
455 | |
|
|
456 | |
323 | =item aio_stat $fh_or_path, $callback->($status) |
457 | =item aio_stat $fh_or_path, $callback->($status) |
324 | |
458 | |
325 | =item aio_lstat $fh, $callback->($status) |
459 | =item aio_lstat $fh, $callback->($status) |
326 | |
460 | |
327 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
461 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
… | |
… | |
340 | aio_stat "/etc/passwd", sub { |
474 | aio_stat "/etc/passwd", sub { |
341 | $_[0] and die "stat failed: $!"; |
475 | $_[0] and die "stat failed: $!"; |
342 | print "size is ", -s _, "\n"; |
476 | print "size is ", -s _, "\n"; |
343 | }; |
477 | }; |
344 | |
478 | |
|
|
479 | |
|
|
480 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
|
|
481 | |
|
|
482 | Works like perl's C<utime> function (including the special case of $atime |
|
|
483 | and $mtime being undef). Fractional times are supported if the underlying |
|
|
484 | syscalls support them. |
|
|
485 | |
|
|
486 | When called with a pathname, uses utimes(2) if available, otherwise |
|
|
487 | utime(2). If called on a file descriptor, uses futimes(2) if available, |
|
|
488 | otherwise returns ENOSYS, so this is not portable. |
|
|
489 | |
|
|
490 | Examples: |
|
|
491 | |
|
|
492 | # set atime and mtime to current time (basically touch(1)): |
|
|
493 | aio_utime "path", undef, undef; |
|
|
494 | # set atime to current time and mtime to beginning of the epoch: |
|
|
495 | aio_utime "path", time, undef; # undef==0 |
|
|
496 | |
|
|
497 | |
|
|
498 | =item aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
|
499 | |
|
|
500 | Works like perl's C<chown> function, except that C<undef> for either $uid |
|
|
501 | or $gid is being interpreted as "do not change" (but -1 can also be used). |
|
|
502 | |
|
|
503 | Examples: |
|
|
504 | |
|
|
505 | # same as "chown root path" in the shell: |
|
|
506 | aio_chown "path", 0, -1; |
|
|
507 | # same as above: |
|
|
508 | aio_chown "path", 0, undef; |
|
|
509 | |
|
|
510 | |
|
|
511 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
|
|
512 | |
|
|
513 | Works like truncate(2) or ftruncate(2). |
|
|
514 | |
|
|
515 | |
|
|
516 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
|
|
517 | |
|
|
518 | Works like perl's C<chmod> function. |
|
|
519 | |
|
|
520 | |
345 | =item aio_unlink $pathname, $callback->($status) |
521 | =item aio_unlink $pathname, $callback->($status) |
346 | |
522 | |
347 | Asynchronously unlink (delete) a file and call the callback with the |
523 | Asynchronously unlink (delete) a file and call the callback with the |
348 | result code. |
524 | result code. |
349 | |
525 | |
|
|
526 | |
|
|
527 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
|
|
528 | |
|
|
529 | [EXPERIMENTAL] |
|
|
530 | |
|
|
531 | Asynchronously create a device node (or fifo). See mknod(2). |
|
|
532 | |
|
|
533 | The only (POSIX-) portable way of calling this function is: |
|
|
534 | |
|
|
535 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
|
|
536 | |
|
|
537 | |
350 | =item aio_link $srcpath, $dstpath, $callback->($status) |
538 | =item aio_link $srcpath, $dstpath, $callback->($status) |
351 | |
539 | |
352 | Asynchronously create a new link to the existing object at C<$srcpath> at |
540 | Asynchronously create a new link to the existing object at C<$srcpath> at |
353 | 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. |
354 | |
542 | |
|
|
543 | |
355 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
544 | =item aio_symlink $srcpath, $dstpath, $callback->($status) |
356 | |
545 | |
357 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
546 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
358 | the path C<$dstpath> and call the callback with the result code. |
547 | the path C<$dstpath> and call the callback with the result code. |
359 | |
548 | |
|
|
549 | |
|
|
550 | =item aio_readlink $path, $callback->($link) |
|
|
551 | |
|
|
552 | Asynchronously read the symlink specified by C<$path> and pass it to |
|
|
553 | the callback. If an error occurs, nothing or undef gets passed to the |
|
|
554 | callback. |
|
|
555 | |
|
|
556 | |
360 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
557 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
361 | |
558 | |
362 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
559 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
363 | rename(2) and call the callback with the result code. |
560 | rename(2) and call the callback with the result code. |
364 | |
561 | |
|
|
562 | |
|
|
563 | =item aio_mkdir $pathname, $mode, $callback->($status) |
|
|
564 | |
|
|
565 | Asynchronously mkdir (create) a directory and call the callback with |
|
|
566 | the result code. C<$mode> will be modified by the umask at the time the |
|
|
567 | request is executed, so do not change your umask. |
|
|
568 | |
|
|
569 | |
365 | =item aio_rmdir $pathname, $callback->($status) |
570 | =item aio_rmdir $pathname, $callback->($status) |
366 | |
571 | |
367 | Asynchronously rmdir (delete) a directory and call the callback with the |
572 | Asynchronously rmdir (delete) a directory and call the callback with the |
368 | result code. |
573 | result code. |
|
|
574 | |
369 | |
575 | |
370 | =item aio_readdir $pathname, $callback->($entries) |
576 | =item aio_readdir $pathname, $callback->($entries) |
371 | |
577 | |
372 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
578 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
373 | directory (i.e. opendir + readdir + closedir). The entries will not be |
579 | directory (i.e. opendir + readdir + closedir). The entries will not be |
374 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
580 | sorted, and will B<NOT> include the C<.> and C<..> entries. |
375 | |
581 | |
376 | The callback a single argument which is either C<undef> or an array-ref |
582 | The callback a single argument which is either C<undef> or an array-ref |
377 | with the filenames. |
583 | with the filenames. |
378 | |
584 | |
|
|
585 | |
|
|
586 | =item aio_load $path, $data, $callback->($status) |
|
|
587 | |
|
|
588 | This is a composite request that tries to fully load the given file into |
|
|
589 | memory. Status is the same as with aio_read. |
|
|
590 | |
|
|
591 | =cut |
|
|
592 | |
|
|
593 | sub aio_load($$;$) { |
|
|
594 | aio_block { |
|
|
595 | my ($path, undef, $cb) = @_; |
|
|
596 | my $data = \$_[1]; |
|
|
597 | |
|
|
598 | my $pri = aioreq_pri; |
|
|
599 | my $grp = aio_group $cb; |
|
|
600 | |
|
|
601 | aioreq_pri $pri; |
|
|
602 | add $grp aio_open $path, O_RDONLY, 0, sub { |
|
|
603 | my $fh = shift |
|
|
604 | or return $grp->result (-1); |
|
|
605 | |
|
|
606 | aioreq_pri $pri; |
|
|
607 | add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub { |
|
|
608 | $grp->result ($_[0]); |
|
|
609 | }; |
|
|
610 | }; |
|
|
611 | |
|
|
612 | $grp |
|
|
613 | } |
|
|
614 | } |
|
|
615 | |
|
|
616 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
|
|
617 | |
|
|
618 | Try to copy the I<file> (directories not supported as either source or |
|
|
619 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
|
|
620 | the C<0> (error) or C<-1> ok. |
|
|
621 | |
|
|
622 | This is a composite request that it creates the destination file with |
|
|
623 | mode 0200 and copies the contents of the source file into it using |
|
|
624 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
|
|
625 | uid/gid, in that order. |
|
|
626 | |
|
|
627 | If an error occurs, the partial destination file will be unlinked, if |
|
|
628 | possible, except when setting atime, mtime, access mode and uid/gid, where |
|
|
629 | errors are being ignored. |
|
|
630 | |
|
|
631 | =cut |
|
|
632 | |
|
|
633 | sub aio_copy($$;$) { |
|
|
634 | aio_block { |
|
|
635 | my ($src, $dst, $cb) = @_; |
|
|
636 | |
|
|
637 | my $pri = aioreq_pri; |
|
|
638 | my $grp = aio_group $cb; |
|
|
639 | |
|
|
640 | aioreq_pri $pri; |
|
|
641 | add $grp aio_open $src, O_RDONLY, 0, sub { |
|
|
642 | if (my $src_fh = $_[0]) { |
|
|
643 | my @stat = stat $src_fh; |
|
|
644 | |
|
|
645 | aioreq_pri $pri; |
|
|
646 | add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub { |
|
|
647 | if (my $dst_fh = $_[0]) { |
|
|
648 | aioreq_pri $pri; |
|
|
649 | add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub { |
|
|
650 | if ($_[0] == $stat[7]) { |
|
|
651 | $grp->result (0); |
|
|
652 | close $src_fh; |
|
|
653 | |
|
|
654 | # those should not normally block. should. should. |
|
|
655 | utime $stat[8], $stat[9], $dst; |
|
|
656 | chmod $stat[2] & 07777, $dst_fh; |
|
|
657 | chown $stat[4], $stat[5], $dst_fh; |
|
|
658 | |
|
|
659 | aioreq_pri $pri; |
|
|
660 | add $grp aio_close $dst_fh; |
|
|
661 | } else { |
|
|
662 | $grp->result (-1); |
|
|
663 | close $src_fh; |
|
|
664 | close $dst_fh; |
|
|
665 | |
|
|
666 | aioreq $pri; |
|
|
667 | add $grp aio_unlink $dst; |
|
|
668 | } |
|
|
669 | }; |
|
|
670 | } else { |
|
|
671 | $grp->result (-1); |
|
|
672 | } |
|
|
673 | }, |
|
|
674 | |
|
|
675 | } else { |
|
|
676 | $grp->result (-1); |
|
|
677 | } |
|
|
678 | }; |
|
|
679 | |
|
|
680 | $grp |
|
|
681 | } |
|
|
682 | } |
|
|
683 | |
|
|
684 | =item aio_move $srcpath, $dstpath, $callback->($status) |
|
|
685 | |
|
|
686 | Try to move the I<file> (directories not supported as either source or |
|
|
687 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
|
|
688 | the C<0> (error) or C<-1> ok. |
|
|
689 | |
|
|
690 | This is a composite request that tries to rename(2) the file first. If |
|
|
691 | rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if |
|
|
692 | that is successful, unlinking the C<$srcpath>. |
|
|
693 | |
|
|
694 | =cut |
|
|
695 | |
|
|
696 | sub aio_move($$;$) { |
|
|
697 | aio_block { |
|
|
698 | my ($src, $dst, $cb) = @_; |
|
|
699 | |
|
|
700 | my $pri = aioreq_pri; |
|
|
701 | my $grp = aio_group $cb; |
|
|
702 | |
|
|
703 | aioreq_pri $pri; |
|
|
704 | add $grp aio_rename $src, $dst, sub { |
|
|
705 | if ($_[0] && $! == EXDEV) { |
|
|
706 | aioreq_pri $pri; |
|
|
707 | add $grp aio_copy $src, $dst, sub { |
|
|
708 | $grp->result ($_[0]); |
|
|
709 | |
|
|
710 | if (!$_[0]) { |
|
|
711 | aioreq_pri $pri; |
|
|
712 | add $grp aio_unlink $src; |
|
|
713 | } |
|
|
714 | }; |
|
|
715 | } else { |
|
|
716 | $grp->result ($_[0]); |
|
|
717 | } |
|
|
718 | }; |
|
|
719 | |
|
|
720 | $grp |
|
|
721 | } |
|
|
722 | } |
|
|
723 | |
379 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
724 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
380 | |
725 | |
381 | [EXPERIMENTAL due to internal aio_group use] |
|
|
382 | |
|
|
383 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
726 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
384 | separate the entries of directory C<$path> into two sets of names, ones |
727 | efficiently separate the entries of directory C<$path> into two sets of |
385 | you can recurse into (directories or links to them), and ones you cannot |
728 | names, directories you can recurse into (directories), and ones you cannot |
386 | recurse into (everything else). |
729 | recurse into (everything else, including symlinks to directories). |
387 | |
730 | |
388 | C<aio_scandir> is a composite request that creates of many sub requests_ |
731 | C<aio_scandir> is a composite request that creates of many sub requests_ |
389 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
732 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
390 | this function generates. If it is C<< <= 0 >>, then a suitable default |
733 | this function generates. If it is C<< <= 0 >>, then a suitable default |
391 | will be chosen (currently 6). |
734 | will be chosen (currently 4). |
392 | |
735 | |
393 | On error, the callback is called without arguments, otherwise it receives |
736 | On error, the callback is called without arguments, otherwise it receives |
394 | two array-refs with path-relative entry names. |
737 | two array-refs with path-relative entry names. |
395 | |
738 | |
396 | Example: |
739 | Example: |
… | |
… | |
430 | as those tend to return 0 or 1 as link counts, which disables the |
773 | as those tend to return 0 or 1 as link counts, which disables the |
431 | directory counting heuristic. |
774 | directory counting heuristic. |
432 | |
775 | |
433 | =cut |
776 | =cut |
434 | |
777 | |
435 | sub aio_scandir($$$) { |
778 | sub aio_scandir($$;$) { |
|
|
779 | aio_block { |
436 | my ($path, $maxreq, $cb) = @_; |
780 | my ($path, $maxreq, $cb) = @_; |
437 | |
781 | |
|
|
782 | my $pri = aioreq_pri; |
|
|
783 | |
438 | my $grp = aio_group $cb; |
784 | my $grp = aio_group $cb; |
439 | |
785 | |
440 | $maxreq = 6 if $maxreq <= 0; |
786 | $maxreq = 4 if $maxreq <= 0; |
441 | |
787 | |
442 | # stat once |
788 | # stat once |
|
|
789 | aioreq_pri $pri; |
443 | add $grp aio_stat $path, sub { |
790 | add $grp aio_stat $path, sub { |
444 | return $grp->result () if $_[0]; |
791 | return $grp->result () if $_[0]; |
445 | my $now = time; |
792 | my $now = time; |
446 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
793 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
447 | |
794 | |
448 | # read the directory entries |
795 | # read the directory entries |
|
|
796 | aioreq_pri $pri; |
449 | add $grp aio_readdir $path, sub { |
797 | add $grp aio_readdir $path, sub { |
450 | my $entries = shift |
798 | my $entries = shift |
451 | or return $grp->result (); |
799 | or return $grp->result (); |
452 | |
800 | |
453 | # stat the dir another time |
801 | # stat the dir another time |
|
|
802 | aioreq_pri $pri; |
454 | add $grp aio_stat $path, sub { |
803 | add $grp aio_stat $path, sub { |
455 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
804 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
456 | |
805 | |
457 | my $ndirs; |
806 | my $ndirs; |
458 | |
807 | |
459 | # take the slow route if anything looks fishy |
808 | # take the slow route if anything looks fishy |
460 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
809 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
461 | $ndirs = -1; |
810 | $ndirs = -1; |
462 | } else { |
811 | } else { |
463 | # if nlink == 2, we are finished |
812 | # if nlink == 2, we are finished |
464 | # on non-posix-fs's, we rely on nlink < 2 |
813 | # on non-posix-fs's, we rely on nlink < 2 |
465 | $ndirs = (stat _)[3] - 2 |
814 | $ndirs = (stat _)[3] - 2 |
466 | or return $grp->result ([], $entries); |
815 | or return $grp->result ([], $entries); |
467 | } |
816 | } |
468 | |
817 | |
469 | # sort into likely dirs and likely nondirs |
818 | # sort into likely dirs and likely nondirs |
470 | # dirs == files without ".", short entries first |
819 | # dirs == files without ".", short entries first |
471 | $entries = [map $_->[0], |
820 | $entries = [map $_->[0], |
472 | sort { $b->[1] cmp $a->[1] } |
821 | sort { $b->[1] cmp $a->[1] } |
473 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
822 | map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length], |
474 | @$entries]; |
823 | @$entries]; |
475 | |
824 | |
476 | my (@dirs, @nondirs); |
825 | my (@dirs, @nondirs); |
477 | |
826 | |
478 | my ($statcb, $schedcb); |
|
|
479 | my $nreq = 0; |
|
|
480 | |
|
|
481 | my $statgrp = add $grp aio_group; |
827 | my $statgrp = add $grp aio_group sub { |
482 | |
|
|
483 | $schedcb = sub { |
|
|
484 | if (@$entries) { |
|
|
485 | if ($nreq < $maxreq) { |
|
|
486 | my $ent = pop @$entries; |
|
|
487 | $nreq++; |
|
|
488 | add $statgrp aio_stat "$path/$ent/.", sub { $statcb->($_[0], $ent) }; |
|
|
489 | } |
|
|
490 | } elsif (!$nreq) { |
|
|
491 | # finished |
|
|
492 | $statgrp->cancel; |
|
|
493 | undef $statcb; |
|
|
494 | undef $schedcb; |
|
|
495 | $grp->result (\@dirs, \@nondirs); |
828 | $grp->result (\@dirs, \@nondirs); |
496 | } |
829 | }; |
|
|
830 | |
|
|
831 | limit $statgrp $maxreq; |
|
|
832 | feed $statgrp sub { |
|
|
833 | return unless @$entries; |
|
|
834 | my $entry = pop @$entries; |
|
|
835 | |
|
|
836 | aioreq_pri $pri; |
|
|
837 | add $statgrp aio_stat "$path/$entry/.", sub { |
|
|
838 | if ($_[0] < 0) { |
|
|
839 | push @nondirs, $entry; |
|
|
840 | } else { |
|
|
841 | # need to check for real directory |
|
|
842 | aioreq_pri $pri; |
|
|
843 | add $statgrp aio_lstat "$path/$entry", sub { |
|
|
844 | if (-d _) { |
|
|
845 | push @dirs, $entry; |
|
|
846 | |
|
|
847 | unless (--$ndirs) { |
|
|
848 | push @nondirs, @$entries; |
|
|
849 | feed $statgrp; |
|
|
850 | } |
|
|
851 | } else { |
|
|
852 | push @nondirs, $entry; |
|
|
853 | } |
|
|
854 | } |
|
|
855 | } |
|
|
856 | }; |
|
|
857 | }; |
497 | }; |
858 | }; |
498 | $statcb = sub { |
|
|
499 | my ($status, $entry) = @_; |
|
|
500 | |
|
|
501 | if ($status < 0) { |
|
|
502 | $nreq--; |
|
|
503 | push @nondirs, $entry; |
|
|
504 | &$schedcb; |
|
|
505 | } else { |
|
|
506 | # need to check for real directory |
|
|
507 | add $grp aio_lstat "$path/$entry", sub { |
|
|
508 | $nreq--; |
|
|
509 | |
|
|
510 | if (-d _) { |
|
|
511 | push @dirs, $entry; |
|
|
512 | |
|
|
513 | if (!--$ndirs) { |
|
|
514 | push @nondirs, @$entries; |
|
|
515 | $entries = []; |
|
|
516 | } |
|
|
517 | } else { |
|
|
518 | push @nondirs, $entry; |
|
|
519 | } |
|
|
520 | |
|
|
521 | &$schedcb; |
|
|
522 | } |
|
|
523 | } |
|
|
524 | }; |
|
|
525 | |
|
|
526 | &$schedcb while @$entries && $nreq < $maxreq; |
|
|
527 | }; |
859 | }; |
528 | }; |
860 | }; |
|
|
861 | |
|
|
862 | $grp |
529 | }; |
863 | } |
530 | |
|
|
531 | $grp |
|
|
532 | } |
864 | } |
|
|
865 | |
|
|
866 | =item aio_rmtree $path, $callback->($status) |
|
|
867 | |
|
|
868 | Delete a directory tree starting (and including) C<$path>, return the |
|
|
869 | status of the final C<rmdir> only. This is a composite request that |
|
|
870 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
|
|
871 | everything else. |
|
|
872 | |
|
|
873 | =cut |
|
|
874 | |
|
|
875 | sub aio_rmtree; |
|
|
876 | sub aio_rmtree($;$) { |
|
|
877 | aio_block { |
|
|
878 | my ($path, $cb) = @_; |
|
|
879 | |
|
|
880 | my $pri = aioreq_pri; |
|
|
881 | my $grp = aio_group $cb; |
|
|
882 | |
|
|
883 | aioreq_pri $pri; |
|
|
884 | add $grp aio_scandir $path, 0, sub { |
|
|
885 | my ($dirs, $nondirs) = @_; |
|
|
886 | |
|
|
887 | my $dirgrp = aio_group sub { |
|
|
888 | add $grp aio_rmdir $path, sub { |
|
|
889 | $grp->result ($_[0]); |
|
|
890 | }; |
|
|
891 | }; |
|
|
892 | |
|
|
893 | (aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs; |
|
|
894 | (aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs; |
|
|
895 | |
|
|
896 | add $grp $dirgrp; |
|
|
897 | }; |
|
|
898 | |
|
|
899 | $grp |
|
|
900 | } |
|
|
901 | } |
|
|
902 | |
|
|
903 | =item aio_sync $callback->($status) |
|
|
904 | |
|
|
905 | Asynchronously call sync and call the callback when finished. |
533 | |
906 | |
534 | =item aio_fsync $fh, $callback->($status) |
907 | =item aio_fsync $fh, $callback->($status) |
535 | |
908 | |
536 | Asynchronously call fsync on the given filehandle and call the callback |
909 | Asynchronously call fsync on the given filehandle and call the callback |
537 | with the fsync result code. |
910 | with the fsync result code. |
… | |
… | |
542 | callback with the fdatasync result code. |
915 | callback with the fdatasync result code. |
543 | |
916 | |
544 | If this call isn't available because your OS lacks it or it couldn't be |
917 | If this call isn't available because your OS lacks it or it couldn't be |
545 | detected, it will be emulated by calling C<fsync> instead. |
918 | detected, it will be emulated by calling C<fsync> instead. |
546 | |
919 | |
|
|
920 | =item aio_pathsync $path, $callback->($status) |
|
|
921 | |
|
|
922 | This request tries to open, fsync and close the given path. This is a |
|
|
923 | composite request intended tosync directories after directory operations |
|
|
924 | (E.g. rename). This might not work on all operating systems or have any |
|
|
925 | specific effect, but usually it makes sure that directory changes get |
|
|
926 | written to disc. It works for anything that can be opened for read-only, |
|
|
927 | not just directories. |
|
|
928 | |
|
|
929 | Passes C<0> when everything went ok, and C<-1> on error. |
|
|
930 | |
|
|
931 | =cut |
|
|
932 | |
|
|
933 | sub aio_pathsync($;$) { |
|
|
934 | aio_block { |
|
|
935 | my ($path, $cb) = @_; |
|
|
936 | |
|
|
937 | my $pri = aioreq_pri; |
|
|
938 | my $grp = aio_group $cb; |
|
|
939 | |
|
|
940 | aioreq_pri $pri; |
|
|
941 | add $grp aio_open $path, O_RDONLY, 0, sub { |
|
|
942 | my ($fh) = @_; |
|
|
943 | if ($fh) { |
|
|
944 | aioreq_pri $pri; |
|
|
945 | add $grp aio_fsync $fh, sub { |
|
|
946 | $grp->result ($_[0]); |
|
|
947 | |
|
|
948 | aioreq_pri $pri; |
|
|
949 | add $grp aio_close $fh; |
|
|
950 | }; |
|
|
951 | } else { |
|
|
952 | $grp->result (-1); |
|
|
953 | } |
|
|
954 | }; |
|
|
955 | |
|
|
956 | $grp |
|
|
957 | } |
|
|
958 | } |
|
|
959 | |
547 | =item aio_group $callback->(...) |
960 | =item aio_group $callback->(...) |
548 | |
|
|
549 | [EXPERIMENTAL] |
|
|
550 | |
961 | |
551 | This is a very special aio request: Instead of doing something, it is a |
962 | This is a very special aio request: Instead of doing something, it is a |
552 | container for other aio requests, which is useful if you want to bundle |
963 | container for other aio requests, which is useful if you want to bundle |
553 | many requests into a single, composite, request. |
964 | many requests into a single, composite, request with a definite callback |
|
|
965 | and the ability to cancel the whole request with its subrequests. |
554 | |
966 | |
555 | Returns an object of class L<IO::AIO::GRP>. See its documentation below |
967 | Returns an object of class L<IO::AIO::GRP>. See its documentation below |
556 | for more info. |
968 | for more info. |
557 | |
969 | |
558 | Example: |
970 | Example: |
… | |
… | |
577 | phase and still requires a worker thread. Thus, the callback will not |
989 | phase and still requires a worker thread. Thus, the callback will not |
578 | be executed immediately but only after other requests in the queue have |
990 | be executed immediately but only after other requests in the queue have |
579 | entered their execution phase. This can be used to measure request |
991 | entered their execution phase. This can be used to measure request |
580 | latency. |
992 | latency. |
581 | |
993 | |
582 | =item IO::AIO::aio_sleep $fractional_seconds, $callback->() *NOT EXPORTED* |
994 | =item IO::AIO::aio_busy $fractional_seconds, $callback->() *NOT EXPORTED* |
583 | |
995 | |
584 | Mainly used for debugging and benchmarking, this aio request puts one of |
996 | Mainly used for debugging and benchmarking, this aio request puts one of |
585 | the request workers to sleep for the given time. |
997 | the request workers to sleep for the given time. |
586 | |
998 | |
587 | While it is theoretically handy to have simple I/O scheduling requests |
999 | While it is theoretically handy to have simple I/O scheduling requests |
588 | like sleep and file handle readable/writable, the overhead this creates |
1000 | like sleep and file handle readable/writable, the overhead this creates is |
589 | is immense, so do not use this function except to put your application |
1001 | immense (it blocks a thread for a long time) so do not use this function |
590 | under artificial I/O pressure. |
1002 | except to put your application under artificial I/O pressure. |
591 | |
1003 | |
592 | =back |
1004 | =back |
593 | |
1005 | |
594 | =head2 IO::AIO::REQ CLASS |
1006 | =head2 IO::AIO::REQ CLASS |
595 | |
1007 | |
596 | All non-aggregate C<aio_*> functions return an object of this class when |
1008 | All non-aggregate C<aio_*> functions return an object of this class when |
597 | called in non-void context. |
1009 | called in non-void context. |
598 | |
|
|
599 | A request always moves through the following five states in its lifetime, |
|
|
600 | in order: B<ready> (request has been created, but has not been executed |
|
|
601 | yet), B<execute> (request is currently being executed), B<pending> |
|
|
602 | (request has been executed but callback has not been called yet), |
|
|
603 | B<result> (results are being processed synchronously, includes calling the |
|
|
604 | callback) and B<done> (request has reached the end of its lifetime and |
|
|
605 | holds no resources anymore). |
|
|
606 | |
1010 | |
607 | =over 4 |
1011 | =over 4 |
608 | |
1012 | |
609 | =item cancel $req |
1013 | =item cancel $req |
610 | |
1014 | |
… | |
… | |
664 | =item * They can also can also be added to other IO::AIO::GRP objects. |
1068 | =item * They can also can also be added to other IO::AIO::GRP objects. |
665 | |
1069 | |
666 | =item * You must not add requests to a group from within the group callback (or |
1070 | =item * You must not add requests to a group from within the group callback (or |
667 | any later time). |
1071 | any later time). |
668 | |
1072 | |
669 | =item * This does not harmonise well with C<max_outstanding>, so best do |
|
|
670 | not combine C<aio_group> with it. Groups and feeders are recommended for |
|
|
671 | this kind of concurrency-limiting. |
|
|
672 | |
|
|
673 | =back |
1073 | =back |
674 | |
1074 | |
675 | Their lifetime, simplified, looks like this: when they are empty, they |
1075 | Their lifetime, simplified, looks like this: when they are empty, they |
676 | will finish very quickly. If they contain only requests that are in the |
1076 | will finish very quickly. If they contain only requests that are in the |
677 | C<done> state, they will also finish. Otherwise they will continue to |
1077 | C<done> state, they will also finish. Otherwise they will continue to |
… | |
… | |
692 | be added, including other groups, as long as you do not create circular |
1092 | be added, including other groups, as long as you do not create circular |
693 | dependencies. |
1093 | dependencies. |
694 | |
1094 | |
695 | Returns all its arguments. |
1095 | Returns all its arguments. |
696 | |
1096 | |
|
|
1097 | =item $grp->cancel_subs |
|
|
1098 | |
|
|
1099 | Cancel all subrequests and clears any feeder, but not the group request |
|
|
1100 | itself. Useful when you queued a lot of events but got a result early. |
|
|
1101 | |
697 | =item $grp->result (...) |
1102 | =item $grp->result (...) |
698 | |
1103 | |
699 | Set the result value(s) that will be passed to the group callback when all |
1104 | Set the result value(s) that will be passed to the group callback when all |
700 | subrequests have finished. By default, no argument will be passed. |
1105 | subrequests have finished and set the groups errno to the current value |
|
|
1106 | of errno (just like calling C<errno> without an error number). By default, |
|
|
1107 | no argument will be passed and errno is zero. |
|
|
1108 | |
|
|
1109 | =item $grp->errno ([$errno]) |
|
|
1110 | |
|
|
1111 | Sets the group errno value to C<$errno>, or the current value of errno |
|
|
1112 | when the argument is missing. |
|
|
1113 | |
|
|
1114 | Every aio request has an associated errno value that is restored when |
|
|
1115 | the callback is invoked. This method lets you change this value from its |
|
|
1116 | default (0). |
|
|
1117 | |
|
|
1118 | Calling C<result> will also set errno, so make sure you either set C<$!> |
|
|
1119 | before the call to C<result>, or call c<errno> after it. |
701 | |
1120 | |
702 | =item feed $grp $callback->($grp) |
1121 | =item feed $grp $callback->($grp) |
703 | |
|
|
704 | [VERY EXPERIMENTAL] |
|
|
705 | |
1122 | |
706 | Sets a feeder/generator on this group: every group can have an attached |
1123 | Sets a feeder/generator on this group: every group can have an attached |
707 | generator that generates requests if idle. The idea behind this is that, |
1124 | generator that generates requests if idle. The idea behind this is that, |
708 | although you could just queue as many requests as you want in a group, |
1125 | although you could just queue as many requests as you want in a group, |
709 | this might starve other requests for a potentially long time. For |
1126 | this might starve other requests for a potentially long time. For |
… | |
… | |
746 | |
1163 | |
747 | =back |
1164 | =back |
748 | |
1165 | |
749 | =head2 SUPPORT FUNCTIONS |
1166 | =head2 SUPPORT FUNCTIONS |
750 | |
1167 | |
|
|
1168 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
|
|
1169 | |
751 | =over 4 |
1170 | =over 4 |
752 | |
1171 | |
753 | =item $fileno = IO::AIO::poll_fileno |
1172 | =item $fileno = IO::AIO::poll_fileno |
754 | |
1173 | |
755 | Return the I<request result pipe file descriptor>. This filehandle must be |
1174 | Return the I<request result pipe file descriptor>. This filehandle must be |
… | |
… | |
759 | |
1178 | |
760 | See C<poll_cb> for an example. |
1179 | See C<poll_cb> for an example. |
761 | |
1180 | |
762 | =item IO::AIO::poll_cb |
1181 | =item IO::AIO::poll_cb |
763 | |
1182 | |
764 | Process all outstanding events on the result pipe. You have to call this |
1183 | Process some outstanding events on the result pipe. You have to call this |
765 | regularly. Returns the number of events processed. Returns immediately |
1184 | regularly. Returns the number of events processed. Returns immediately |
766 | when no events are outstanding. |
1185 | when no events are outstanding. The amount of events processed depends on |
|
|
1186 | the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
|
|
1187 | |
|
|
1188 | If not all requests were processed for whatever reason, the filehandle |
|
|
1189 | will still be ready when C<poll_cb> returns. |
767 | |
1190 | |
768 | Example: Install an Event watcher that automatically calls |
1191 | Example: Install an Event watcher that automatically calls |
769 | IO::AIO::poll_cb with high priority: |
1192 | IO::AIO::poll_cb with high priority: |
770 | |
1193 | |
771 | Event->io (fd => IO::AIO::poll_fileno, |
1194 | Event->io (fd => IO::AIO::poll_fileno, |
772 | poll => 'r', async => 1, |
1195 | poll => 'r', async => 1, |
773 | cb => \&IO::AIO::poll_cb); |
1196 | cb => \&IO::AIO::poll_cb); |
774 | |
1197 | |
|
|
1198 | =item IO::AIO::max_poll_reqs $nreqs |
|
|
1199 | |
|
|
1200 | =item IO::AIO::max_poll_time $seconds |
|
|
1201 | |
|
|
1202 | These set the maximum number of requests (default C<0>, meaning infinity) |
|
|
1203 | that are being processed by C<IO::AIO::poll_cb> in one call, respectively |
|
|
1204 | the maximum amount of time (default C<0>, meaning infinity) spent in |
|
|
1205 | C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount |
|
|
1206 | of time C<poll_cb> is allowed to use). |
|
|
1207 | |
|
|
1208 | Setting C<max_poll_time> to a non-zero value creates an overhead of one |
|
|
1209 | syscall per request processed, which is not normally a problem unless your |
|
|
1210 | callbacks are really really fast or your OS is really really slow (I am |
|
|
1211 | not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead. |
|
|
1212 | |
|
|
1213 | Setting these is useful if you want to ensure some level of |
|
|
1214 | interactiveness when perl is not fast enough to process all requests in |
|
|
1215 | time. |
|
|
1216 | |
|
|
1217 | For interactive programs, values such as C<0.01> to C<0.1> should be fine. |
|
|
1218 | |
|
|
1219 | Example: Install an Event watcher that automatically calls |
|
|
1220 | IO::AIO::poll_cb with low priority, to ensure that other parts of the |
|
|
1221 | program get the CPU sometimes even under high AIO load. |
|
|
1222 | |
|
|
1223 | # try not to spend much more than 0.1s in poll_cb |
|
|
1224 | IO::AIO::max_poll_time 0.1; |
|
|
1225 | |
|
|
1226 | # use a low priority so other tasks have priority |
|
|
1227 | Event->io (fd => IO::AIO::poll_fileno, |
|
|
1228 | poll => 'r', nice => 1, |
|
|
1229 | cb => &IO::AIO::poll_cb); |
|
|
1230 | |
775 | =item IO::AIO::poll_wait |
1231 | =item IO::AIO::poll_wait |
776 | |
1232 | |
|
|
1233 | If there are any outstanding requests and none of them in the result |
777 | Wait till the result filehandle becomes ready for reading (simply does a |
1234 | phase, wait till the result filehandle becomes ready for reading (simply |
778 | C<select> on the filehandle. This is useful if you want to synchronously wait |
1235 | does a C<select> on the filehandle. This is useful if you want to |
779 | for some requests to finish). |
1236 | synchronously wait for some requests to finish). |
780 | |
1237 | |
781 | See C<nreqs> for an example. |
1238 | See C<nreqs> for an example. |
782 | |
1239 | |
|
|
1240 | =item IO::AIO::poll |
|
|
1241 | |
|
|
1242 | Waits until some requests have been handled. |
|
|
1243 | |
|
|
1244 | Returns the number of requests processed, but is otherwise strictly |
|
|
1245 | equivalent to: |
|
|
1246 | |
|
|
1247 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1248 | |
783 | =item IO::AIO::nreqs |
1249 | =item IO::AIO::flush |
784 | |
1250 | |
785 | Returns the number of requests currently outstanding (i.e. for which their |
1251 | Wait till all outstanding AIO requests have been handled. |
786 | callback has not been invoked yet). |
|
|
787 | |
1252 | |
788 | Example: wait till there are no outstanding requests anymore: |
1253 | Strictly equivalent to: |
789 | |
1254 | |
790 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1255 | IO::AIO::poll_wait, IO::AIO::poll_cb |
791 | while IO::AIO::nreqs; |
1256 | while IO::AIO::nreqs; |
792 | |
1257 | |
793 | =item IO::AIO::flush |
1258 | =back |
794 | |
1259 | |
795 | Wait till all outstanding AIO requests have been handled. |
1260 | =head3 CONTROLLING THE NUMBER OF THREADS |
796 | |
1261 | |
797 | Strictly equivalent to: |
1262 | =over |
798 | |
|
|
799 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
800 | while IO::AIO::nreqs; |
|
|
801 | |
|
|
802 | =item IO::AIO::poll |
|
|
803 | |
|
|
804 | Waits until some requests have been handled. |
|
|
805 | |
|
|
806 | Strictly equivalent to: |
|
|
807 | |
|
|
808 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
809 | if IO::AIO::nreqs; |
|
|
810 | |
1263 | |
811 | =item IO::AIO::min_parallel $nthreads |
1264 | =item IO::AIO::min_parallel $nthreads |
812 | |
1265 | |
813 | Set the minimum number of AIO threads to C<$nthreads>. The current |
1266 | Set the minimum number of AIO threads to C<$nthreads>. The current |
814 | default is C<8>, which means eight asynchronous operations can execute |
1267 | default is C<8>, which means eight asynchronous operations can execute |
815 | concurrently at any one time (the number of outstanding requests, |
1268 | concurrently at any one time (the number of outstanding requests, |
816 | however, is unlimited). |
1269 | however, is unlimited). |
817 | |
1270 | |
818 | IO::AIO starts threads only on demand, when an AIO request is queued and |
1271 | IO::AIO starts threads only on demand, when an AIO request is queued and |
819 | no free thread exists. |
1272 | no free thread exists. Please note that queueing up a hundred requests can |
|
|
1273 | create demand for a hundred threads, even if it turns out that everything |
|
|
1274 | is in the cache and could have been processed faster by a single thread. |
820 | |
1275 | |
821 | It is recommended to keep the number of threads relatively low, as some |
1276 | It is recommended to keep the number of threads relatively low, as some |
822 | Linux kernel versions will scale negatively with the number of threads |
1277 | Linux kernel versions will scale negatively with the number of threads |
823 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
1278 | (higher parallelity => MUCH higher latency). With current Linux 2.6 |
824 | versions, 4-32 threads should be fine. |
1279 | versions, 4-32 threads should be fine. |
… | |
… | |
838 | This module automatically runs C<max_parallel 0> at program end, to ensure |
1293 | This module automatically runs C<max_parallel 0> at program end, to ensure |
839 | that all threads are killed and that there are no outstanding requests. |
1294 | that all threads are killed and that there are no outstanding requests. |
840 | |
1295 | |
841 | Under normal circumstances you don't need to call this function. |
1296 | Under normal circumstances you don't need to call this function. |
842 | |
1297 | |
|
|
1298 | =item IO::AIO::max_idle $nthreads |
|
|
1299 | |
|
|
1300 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
|
|
1301 | threads that did not get a request to process within 10 seconds). That |
|
|
1302 | means if a thread becomes idle while C<$nthreads> other threads are also |
|
|
1303 | idle, it will free its resources and exit. |
|
|
1304 | |
|
|
1305 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
|
|
1306 | to allow for extremely high load situations, but want to free resources |
|
|
1307 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
|
|
1308 | |
|
|
1309 | The default is probably ok in most situations, especially if thread |
|
|
1310 | creation is fast. If thread creation is very slow on your system you might |
|
|
1311 | want to use larger values. |
|
|
1312 | |
843 | =item $oldnreqs = IO::AIO::max_outstanding $nreqs |
1313 | =item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs |
844 | |
1314 | |
845 | [DEPRECATED] |
1315 | This is a very bad function to use in interactive programs because it |
|
|
1316 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
|
|
1317 | use an C<aio_group> together with a feed callback. |
846 | |
1318 | |
847 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
1319 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
848 | try to queue up more than this number of requests, the caller will block until |
1320 | do queue up more than this number of requests, the next call to the |
849 | some requests have been handled. |
1321 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
|
|
1322 | function will block until the limit is no longer exceeded. |
850 | |
1323 | |
851 | The default is very large, so normally there is no practical limit. If you |
1324 | The default value is very large, so there is no practical limit on the |
852 | queue up many requests in a loop it often improves speed if you set |
1325 | number of outstanding requests. |
853 | this to a relatively low number, such as C<100>. |
|
|
854 | |
1326 | |
855 | This function does not work well together with C<aio_group>'s, and their |
1327 | You can still queue as many requests as you want. Therefore, |
856 | feeder interface is better suited to limiting concurrency, so do not use |
1328 | C<max_oustsanding> is mainly useful in simple scripts (with low values) or |
857 | this function. |
1329 | as a stop gap to shield against fatal memory overflow (with large values). |
858 | |
|
|
859 | Under normal circumstances you don't need to call this function. |
|
|
860 | |
1330 | |
861 | =back |
1331 | =back |
862 | |
1332 | |
|
|
1333 | =head3 STATISTICAL INFORMATION |
|
|
1334 | |
|
|
1335 | =over |
|
|
1336 | |
|
|
1337 | =item IO::AIO::nreqs |
|
|
1338 | |
|
|
1339 | Returns the number of requests currently in the ready, execute or pending |
|
|
1340 | states (i.e. for which their callback has not been invoked yet). |
|
|
1341 | |
|
|
1342 | Example: wait till there are no outstanding requests anymore: |
|
|
1343 | |
|
|
1344 | IO::AIO::poll_wait, IO::AIO::poll_cb |
|
|
1345 | while IO::AIO::nreqs; |
|
|
1346 | |
|
|
1347 | =item IO::AIO::nready |
|
|
1348 | |
|
|
1349 | Returns the number of requests currently in the ready state (not yet |
|
|
1350 | executed). |
|
|
1351 | |
|
|
1352 | =item IO::AIO::npending |
|
|
1353 | |
|
|
1354 | Returns the number of requests currently in the pending state (executed, |
|
|
1355 | but not yet processed by poll_cb). |
|
|
1356 | |
|
|
1357 | =back |
|
|
1358 | |
863 | =cut |
1359 | =cut |
864 | |
1360 | |
865 | # support function to convert a fd into a perl filehandle |
|
|
866 | sub _fd2fh { |
|
|
867 | return undef if $_[0] < 0; |
|
|
868 | |
|
|
869 | # try to generate nice filehandles |
|
|
870 | my $sym = "IO::AIO::fd#$_[0]"; |
|
|
871 | local *$sym; |
|
|
872 | |
|
|
873 | open *$sym, "+<&=$_[0]" # usually works under any unix |
|
|
874 | or open *$sym, "<&=$_[0]" # cygwin needs this |
|
|
875 | or open *$sym, ">&=$_[0]" # or this |
|
|
876 | or return undef; |
|
|
877 | |
|
|
878 | *$sym |
|
|
879 | } |
|
|
880 | |
|
|
881 | min_parallel 8; |
1361 | min_parallel 8; |
882 | |
1362 | |
883 | END { |
1363 | END { flush } |
884 | max_parallel 0; |
|
|
885 | } |
|
|
886 | |
1364 | |
887 | 1; |
1365 | 1; |
888 | |
1366 | |
889 | =head2 FORK BEHAVIOUR |
1367 | =head2 FORK BEHAVIOUR |
890 | |
1368 | |
891 | This module should do "the right thing" when the process using it forks: |
1369 | This module should do "the right thing" when the process using it forks: |
892 | |
1370 | |
893 | Before the fork, IO::AIO enters a quiescent state where no requests |
1371 | Before the fork, IO::AIO enters a quiescent state where no requests |
894 | can be added in other threads and no results will be processed. After |
1372 | can be added in other threads and no results will be processed. After |
895 | the fork the parent simply leaves the quiescent state and continues |
1373 | the fork the parent simply leaves the quiescent state and continues |
896 | request/result processing, while the child clears the request/result |
1374 | request/result processing, while the child frees the request/result queue |
897 | queue (so the requests started before the fork will only be handled in |
1375 | (so that the requests started before the fork will only be handled in the |
898 | the parent). Threads will be started on demand until the limit ste in the |
1376 | parent). Threads will be started on demand until the limit set in the |
899 | parent process has been reached again. |
1377 | parent process has been reached again. |
900 | |
1378 | |
901 | In short: the parent will, after a short pause, continue as if fork had |
1379 | In short: the parent will, after a short pause, continue as if fork had |
902 | not been called, while the child will act as if IO::AIO has not been used |
1380 | not been called, while the child will act as if IO::AIO has not been used |
903 | yet. |
1381 | yet. |
904 | |
1382 | |
905 | =head2 MEMORY USAGE |
1383 | =head2 MEMORY USAGE |
906 | |
1384 | |
|
|
1385 | Per-request usage: |
|
|
1386 | |
907 | Each aio request uses - depending on your architecture - around 128 bytes |
1387 | Each aio request uses - depending on your architecture - around 100-200 |
908 | of memory. In addition, stat requests need a stat buffer (possibly a few |
1388 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
909 | hundred bytes). Perl scalars and other data passed into aio requests will |
1389 | a few hundred bytes), readdir requires a result buffer and so on. Perl |
910 | also be locked. |
1390 | scalars and other data passed into aio requests will also be locked and |
|
|
1391 | will consume memory till the request has entered the done state. |
911 | |
1392 | |
912 | This is now awfully much, so queuing lots of requests is not usually a |
1393 | This is not awfully much, so queuing lots of requests is not usually a |
913 | problem. |
1394 | problem. |
914 | |
1395 | |
915 | Each thread needs a stack area which is usually around 16k, sometimes much |
1396 | Per-thread usage: |
916 | larger, depending on the OS. |
1397 | |
|
|
1398 | In the execution phase, some aio requests require more memory for |
|
|
1399 | temporary buffers, and each thread requires a stack and other data |
|
|
1400 | structures (usually around 16k-128k, depending on the OS). |
|
|
1401 | |
|
|
1402 | =head1 KNOWN BUGS |
|
|
1403 | |
|
|
1404 | Known bugs will be fixed in the next release. |
917 | |
1405 | |
918 | =head1 SEE ALSO |
1406 | =head1 SEE ALSO |
919 | |
1407 | |
920 | L<Coro::AIO>. |
1408 | L<Coro::AIO>. |
921 | |
1409 | |