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Comparing Coro/Coro.pm (file contents):
Revision 1.103 by root, Thu Jan 4 20:14:19 2007 UTC vs.
Revision 1.123 by root, Mon Apr 16 13:26:43 2007 UTC

50 50
51our $idle; # idle handler 51our $idle; # idle handler
52our $main; # main coroutine 52our $main; # main coroutine
53our $current; # current coroutine 53our $current; # current coroutine
54 54
55our $VERSION = '3.3'; 55our $VERSION = '3.61';
56 56
57our @EXPORT = qw(async cede schedule terminate current unblock_sub); 57our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
58our %EXPORT_TAGS = ( 58our %EXPORT_TAGS = (
59 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 59 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
60); 60);
61our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready)); 61our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));
62 62
185 185
186Create a new asynchronous coroutine and return it's coroutine object 186Create a new asynchronous coroutine and return it's coroutine object
187(usually unused). When the sub returns the new coroutine is automatically 187(usually unused). When the sub returns the new coroutine is automatically
188terminated. 188terminated.
189 189
190Calling C<exit> in a coroutine will not work correctly, so do not do that. 190Calling C<exit> in a coroutine will do the same as calling exit outside
191 191the coroutine. Likewise, when the coroutine dies, the program will exit,
192When the coroutine dies, the program will exit, just as in the main 192just as it would in the main program.
193program.
194 193
195 # create a new coroutine that just prints its arguments 194 # create a new coroutine that just prints its arguments
196 async { 195 async {
197 print "@_\n"; 196 print "@_\n";
198 } 1,2,3,4; 197 } 1,2,3,4;
199 198
200=cut 199=cut
201 200
202sub async(&@) { 201sub async(&@) {
203 my $pid = new Coro @_; 202 my $coro = new Coro @_;
204 $pid->ready; 203 $coro->ready;
205 $pid 204 $coro
205}
206
207=item async_pool { ... } [@args...]
208
209Similar to C<async>, but uses a coroutine pool, so you should not call
210terminate or join (although you are allowed to), and you get a coroutine
211that might have executed other code already (which can be good or bad :).
212
213Also, the block is executed in an C<eval> context and a warning will be
214issued in case of an exception instead of terminating the program, as
215C<async> does. As the coroutine is being reused, stuff like C<on_destroy>
216will not work in the expected way, unless you call terminate or cancel,
217which somehow defeats the purpose of pooling.
218
219The priority will be reset to C<0> after each job, otherwise the coroutine
220will be re-used "as-is".
221
222The pool size is limited to 8 idle coroutines (this can be adjusted by
223changing $Coro::POOL_SIZE), and there can be as many non-idle coros as
224required.
225
226If you are concerned about pooled coroutines growing a lot because a
227single C<async_pool> used a lot of stackspace you can e.g. C<async_pool {
228terminate }> once per second or so to slowly replenish the pool.
229
230=cut
231
232our $POOL_SIZE = 8;
233our @pool;
234
235sub pool_handler {
236 while () {
237 eval {
238 my ($cb, @arg) = @{ delete $current->{_invoke} or return };
239 $cb->(@arg);
240 };
241 warn $@ if $@;
242
243 last if @pool >= $POOL_SIZE;
244 push @pool, $current;
245
246 $current->save (Coro::State::SAVE_DEF);
247 $current->prio (0);
248 schedule;
249 }
250}
251
252sub async_pool(&@) {
253 # this is also inlined into the unlock_scheduler
254 my $coro = (pop @pool or new Coro \&pool_handler);
255
256 $coro->{_invoke} = [@_];
257 $coro->ready;
258
259 $coro
206} 260}
207 261
208=item schedule 262=item schedule
209 263
210Calls the scheduler. Please note that the current coroutine will not be put 264Calls the scheduler. Please note that the current coroutine will not be put
235 289
236"Cede" to other coroutines. This function puts the current coroutine into the 290"Cede" to other coroutines. This function puts the current coroutine into the
237ready queue and calls C<schedule>, which has the effect of giving up the 291ready queue and calls C<schedule>, which has the effect of giving up the
238current "timeslice" to other coroutines of the same or higher priority. 292current "timeslice" to other coroutines of the same or higher priority.
239 293
294Returns true if at least one coroutine switch has happened.
295
240=item Coro::cede_notself 296=item Coro::cede_notself
241 297
242Works like cede, but is not exported by default and will cede to any 298Works like cede, but is not exported by default and will cede to any
243coroutine, regardless of priority, once. 299coroutine, regardless of priority, once.
300
301Returns true if at least one coroutine switch has happened.
244 302
245=item terminate [arg...] 303=item terminate [arg...]
246 304
247Terminates the current coroutine with the given status values (see L<cancel>). 305Terminates the current coroutine with the given status values (see L<cancel>).
248 306
267Create a new coroutine and return it. When the sub returns the coroutine 325Create a new coroutine and return it. When the sub returns the coroutine
268automatically terminates as if C<terminate> with the returned values were 326automatically terminates as if C<terminate> with the returned values were
269called. To make the coroutine run you must first put it into the ready queue 327called. To make the coroutine run you must first put it into the ready queue
270by calling the ready method. 328by calling the ready method.
271 329
272Calling C<exit> in a coroutine will not work correctly, so do not do that. 330See C<async> for additional discussion.
273 331
274=cut 332=cut
275 333
276sub _run_coro { 334sub _run_coro {
277 terminate &{+shift}; 335 terminate &{+shift};
407and C<schedule> would cause a deadlock unless there is an idle handler 465and C<schedule> would cause a deadlock unless there is an idle handler
408that wakes up some coroutines. 466that wakes up some coroutines.
409 467
410=item my $guard = Coro::guard { ... } 468=item my $guard = Coro::guard { ... }
411 469
412This creates and returns a guard object. Nothing happens until the objetc 470This creates and returns a guard object. Nothing happens until the object
413gets destroyed, in which case the codeblock given as argument will be 471gets destroyed, in which case the codeblock given as argument will be
414executed. This is useful to free locks or other resources in case of a 472executed. This is useful to free locks or other resources in case of a
415runtime error or when the coroutine gets canceled, as in both cases the 473runtime error or when the coroutine gets canceled, as in both cases the
416guard block will be executed. The guard object supports only one method, 474guard block will be executed. The guard object supports only one method,
417C<< ->cancel >>, which will keep the codeblock from being executed. 475C<< ->cancel >>, which will keep the codeblock from being executed.
461In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when 519In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when
462creating event callbacks that want to block. 520creating event callbacks that want to block.
463 521
464=cut 522=cut
465 523
466our @unblock_pool;
467our @unblock_queue; 524our @unblock_queue;
468our $UNBLOCK_POOL_SIZE = 2;
469 525
470sub unblock_handler_ { 526# we create a special coro because we want to cede,
471 while () { 527# to reduce pressure on the coro pool (because most callbacks
472 my ($cb, @arg) = @{ delete $Coro::current->{arg} }; 528# return immediately and can be reused) and because we cannot cede
473 $cb->(@arg); 529# inside an event callback.
474
475 last if @unblock_pool >= $UNBLOCK_POOL_SIZE;
476 push @unblock_pool, $Coro::current;
477 schedule;
478 }
479}
480
481our $unblock_scheduler = async { 530our $unblock_scheduler = async {
482 while () { 531 while () {
483 while (my $cb = pop @unblock_queue) { 532 while (my $cb = pop @unblock_queue) {
533 # this is an inlined copy of async_pool
484 my $handler = (pop @unblock_pool or new Coro \&unblock_handler_); 534 my $coro = (pop @pool or new Coro \&pool_handler);
485 $handler->{arg} = $cb; 535
536 $coro->{_invoke} = $cb;
486 $handler->ready; 537 $coro->ready;
487 cede; 538 cede; # for short-lived callbacks, this reduces pressure on the coro pool
488 } 539 }
489 540 schedule; # sleep well
490 schedule;
491 } 541 }
492}; 542};
493 543
494sub unblock_sub(&) { 544sub unblock_sub(&) {
495 my $cb = shift; 545 my $cb = shift;
496 546
497 sub { 547 sub {
498 push @unblock_queue, [$cb, @_]; 548 unshift @unblock_queue, [$cb, @_];
499 $unblock_scheduler->ready; 549 $unblock_scheduler->ready;
500 } 550 }
501} 551}
502 552
503=back 553=back

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