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Comparing Coro/Coro.pm (file contents):
Revision 1.119 by root, Wed Mar 28 14:24:17 2007 UTC vs.
Revision 1.131 by root, Thu Sep 20 12:24:42 2007 UTC

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20 20
21=head1 DESCRIPTION 21=head1 DESCRIPTION
22 22
23This module collection manages coroutines. Coroutines are similar 23This module collection manages coroutines. Coroutines are similar
24to threads but don't run in parallel at the same time even on SMP 24to threads but don't run in parallel at the same time even on SMP
25machines. The specific flavor of coroutine use din this module also 25machines. The specific flavor of coroutine used in this module also
26guarentees you that it will not switch between coroutines unless 26guarantees you that it will not switch between coroutines unless
27necessary, at easily-identified points in your program, so locking and 27necessary, at easily-identified points in your program, so locking and
28parallel access are rarely an issue, making coroutine programming much 28parallel access are rarely an issue, making coroutine programming much
29safer than threads programming. 29safer than threads programming.
30 30
31(Perl, however, does not natively support real threads but instead does a 31(Perl, however, does not natively support real threads but instead does a
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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 = '3.55'; 55our $VERSION = '3.7';
56 56
57our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub); 57our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);
58our %EXPORT_TAGS = ( 58our %EXPORT_TAGS = (
59 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 59 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
60); 60);
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108 108
109The current coroutine (the last coroutine switched to). The initial value 109The current coroutine (the last coroutine switched to). The initial value
110is C<$main> (of course). 110is C<$main> (of course).
111 111
112This variable is B<strictly> I<read-only>. It is provided for performance 112This variable is B<strictly> I<read-only>. It is provided for performance
113reasons. If performance is not essentiel you are encouraged to use the 113reasons. If performance is not essential you are encouraged to use the
114C<Coro::current> function instead. 114C<Coro::current> function instead.
115 115
116=cut 116=cut
117
118$main->{desc} = "[main::]";
117 119
118# maybe some other module used Coro::Specific before... 120# maybe some other module used Coro::Specific before...
119$main->{specific} = $current->{specific} 121$main->{specific} = $current->{specific}
120 if $current; 122 if $current;
121 123
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159# cannot destroy itself. 161# cannot destroy itself.
160my @destroy; 162my @destroy;
161my $manager; 163my $manager;
162 164
163$manager = new Coro sub { 165$manager = new Coro sub {
166 $current->desc ("[coro manager]");
167
164 while () { 168 while () {
165 (shift @destroy)->_cancel 169 (shift @destroy)->_cancel
166 while @destroy; 170 while @destroy;
167 171
168 &schedule; 172 &schedule;
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185 189
186Create a new asynchronous coroutine and return it's coroutine object 190Create a new asynchronous coroutine and return it's coroutine object
187(usually unused). When the sub returns the new coroutine is automatically 191(usually unused). When the sub returns the new coroutine is automatically
188terminated. 192terminated.
189 193
190Calling C<exit> in a coroutine will not work correctly, so do not do that. 194Calling C<exit> in a coroutine will do the same as calling exit outside
191 195the coroutine. Likewise, when the coroutine dies, the program will exit,
192When the coroutine dies, the program will exit, just as in the main 196just as it would in the main program.
193program.
194 197
195 # create a new coroutine that just prints its arguments 198 # create a new coroutine that just prints its arguments
196 async { 199 async {
197 print "@_\n"; 200 print "@_\n";
198 } 1,2,3,4; 201 } 1,2,3,4;
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229terminate }> once per second or so to slowly replenish the pool. 232terminate }> once per second or so to slowly replenish the pool.
230 233
231=cut 234=cut
232 235
233our $POOL_SIZE = 8; 236our $POOL_SIZE = 8;
237our $MAX_POOL_RSS = 64 * 1024;
234our @pool; 238our @pool;
235 239
236sub pool_handler { 240sub pool_handler {
237 while () { 241 while () {
242 $current->{desc} = "[async_pool]";
243
238 eval { 244 eval {
239 my ($cb, @arg) = @{ delete $current->{_invoke} or return }; 245 my ($cb, @arg) = @{ delete $current->{_invoke} or return };
240 $cb->(@arg); 246 $cb->(@arg);
241 }; 247 };
242 warn $@ if $@; 248 warn $@ if $@;
243 249
244 last if @pool >= $POOL_SIZE; 250 last if @pool >= $POOL_SIZE || $current->rss >= $MAX_POOL_RSS;
251
245 push @pool, $current; 252 push @pool, $current;
246 253 $current->{desc} = "[async_pool idle]";
247 $current->save (Coro::State::SAVE_DEF); 254 $current->save (Coro::State::SAVE_DEF);
248 $current->prio (0); 255 $current->prio (0);
249 schedule; 256 schedule;
250 } 257 }
251} 258}
252 259
253sub async_pool(&@) { 260sub async_pool(&@) {
254 # this is also inlined into the unlock_scheduler 261 # this is also inlined into the unlock_scheduler
255 my $coro = (pop @pool or new Coro \&pool_handler); 262 my $coro = (pop @pool) || new Coro \&pool_handler;;
256 263
257 $coro->{_invoke} = [@_]; 264 $coro->{_invoke} = [@_];
258 $coro->ready; 265 $coro->ready;
259 266
260 $coro 267 $coro
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278 # wake up sleeping coroutine 285 # wake up sleeping coroutine
279 $current->ready; 286 $current->ready;
280 undef $current; 287 undef $current;
281 }; 288 };
282 289
283 # call schedule until event occured. 290 # call schedule until event occurred.
284 # in case we are woken up for other reasons 291 # in case we are woken up for other reasons
285 # (current still defined), loop. 292 # (current still defined), loop.
286 Coro::schedule while $current; 293 Coro::schedule while $current;
287 } 294 }
288 295
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326Create a new coroutine and return it. When the sub returns the coroutine 333Create a new coroutine and return it. When the sub returns the coroutine
327automatically terminates as if C<terminate> with the returned values were 334automatically terminates as if C<terminate> with the returned values were
328called. To make the coroutine run you must first put it into the ready queue 335called. To make the coroutine run you must first put it into the ready queue
329by calling the ready method. 336by calling the ready method.
330 337
331Calling C<exit> in a coroutine will not work correctly, so do not do that. 338See C<async> for additional discussion.
332 339
333=cut 340=cut
334 341
335sub _run_coro { 342sub _run_coro {
336 terminate &{+shift}; 343 terminate &{+shift};
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459=over 4 466=over 4
460 467
461=item Coro::nready 468=item Coro::nready
462 469
463Returns the number of coroutines that are currently in the ready state, 470Returns the number of coroutines that are currently in the ready state,
464i.e. that can be swicthed to. The value C<0> means that the only runnable 471i.e. that can be switched to. The value C<0> means that the only runnable
465coroutine is the currently running one, so C<cede> would have no effect, 472coroutine is the currently running one, so C<cede> would have no effect,
466and C<schedule> would cause a deadlock unless there is an idle handler 473and C<schedule> would cause a deadlock unless there is an idle handler
467that wakes up some coroutines. 474that wakes up some coroutines.
468 475
469=item my $guard = Coro::guard { ... } 476=item my $guard = Coro::guard { ... }
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505This utility function takes a BLOCK or code reference and "unblocks" it, 512This utility function takes a BLOCK or code reference and "unblocks" it,
506returning the new coderef. This means that the new coderef will return 513returning the new coderef. This means that the new coderef will return
507immediately without blocking, returning nothing, while the original code 514immediately without blocking, returning nothing, while the original code
508ref will be called (with parameters) from within its own coroutine. 515ref will be called (with parameters) from within its own coroutine.
509 516
510The reason this fucntion exists is that many event libraries (such as the 517The reason this function exists is that many event libraries (such as the
511venerable L<Event|Event> module) are not coroutine-safe (a weaker form 518venerable L<Event|Event> module) are not coroutine-safe (a weaker form
512of thread-safety). This means you must not block within event callbacks, 519of thread-safety). This means you must not block within event callbacks,
513otherwise you might suffer from crashes or worse. 520otherwise you might suffer from crashes or worse.
514 521
515This function allows your callbacks to block by executing them in another 522This function allows your callbacks to block by executing them in another
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527# we create a special coro because we want to cede, 534# we create a special coro because we want to cede,
528# to reduce pressure on the coro pool (because most callbacks 535# to reduce pressure on the coro pool (because most callbacks
529# return immediately and can be reused) and because we cannot cede 536# return immediately and can be reused) and because we cannot cede
530# inside an event callback. 537# inside an event callback.
531our $unblock_scheduler = async { 538our $unblock_scheduler = async {
539 $current->desc ("[unblock_sub scheduler]");
532 while () { 540 while () {
533 while (my $cb = pop @unblock_queue) { 541 while (my $cb = pop @unblock_queue) {
534 # this is an inlined copy of async_pool 542 # this is an inlined copy of async_pool
535 my $coro = (pop @pool or new Coro \&pool_handler); 543 my $coro = (pop @pool or new Coro \&pool_handler);
536 544
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561 569
562 - you must make very sure that no coro is still active on global 570 - you must make very sure that no coro is still active on global
563 destruction. very bad things might happen otherwise (usually segfaults). 571 destruction. very bad things might happen otherwise (usually segfaults).
564 572
565 - this module is not thread-safe. You should only ever use this module 573 - this module is not thread-safe. You should only ever use this module
566 from the same thread (this requirement might be losened in the future 574 from the same thread (this requirement might be loosened in the future
567 to allow per-thread schedulers, but Coro::State does not yet allow 575 to allow per-thread schedulers, but Coro::State does not yet allow
568 this). 576 this).
569 577
570=head1 SEE ALSO 578=head1 SEE ALSO
571 579

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