1 | NAME |
1 | NAME |
2 | Coro - the only real threads in perl |
2 | Coro - the only real threads in perl |
3 | |
3 | |
4 | SYNOPSIS |
4 | SYNOPSIS |
5 | use Coro; |
5 | use Coro; |
6 | |
6 | |
7 | async { |
7 | async { |
8 | # some asynchronous thread of execution |
8 | # some asynchronous thread of execution |
9 | print "2\n"; |
9 | print "2\n"; |
10 | cede; # yield back to main |
10 | cede; # yield back to main |
11 | print "4\n"; |
11 | print "4\n"; |
12 | }; |
12 | }; |
13 | print "1\n"; |
13 | print "1\n"; |
14 | cede; # yield to coroutine |
14 | cede; # yield to coro |
15 | print "3\n"; |
15 | print "3\n"; |
16 | cede; # and again |
16 | cede; # and again |
17 | |
17 | |
18 | # use locking |
18 | # use locking |
19 | use Coro::Semaphore; |
19 | use Coro::Semaphore; |
20 | my $lock = new Coro::Semaphore; |
20 | my $lock = new Coro::Semaphore; |
21 | my $locked; |
21 | my $locked; |
22 | |
22 | |
23 | $lock->down; |
23 | $lock->down; |
24 | $locked = 1; |
24 | $locked = 1; |
25 | $lock->up; |
25 | $lock->up; |
26 | |
26 | |
27 | DESCRIPTION |
27 | DESCRIPTION |
28 | For a tutorial-style introduction, please read the Coro::Intro manpage. |
28 | For a tutorial-style introduction, please read the Coro::Intro manpage. |
29 | This manpage mainly contains reference information. |
29 | This manpage mainly contains reference information. |
30 | |
30 | |
31 | This module collection manages continuations in general, most often in |
31 | This module collection manages continuations in general, most often in |
32 | the form of cooperative threads (also called coroutines in the |
32 | the form of cooperative threads (also called coros, or simply "coro" in |
33 | documentation). They are similar to kernel threads but don't (in |
33 | the documentation). They are similar to kernel threads but don't (in |
34 | general) run in parallel at the same time even on SMP machines. The |
34 | general) run in parallel at the same time even on SMP machines. The |
35 | specific flavor of thread offered by this module also guarantees you |
35 | specific flavor of thread offered by this module also guarantees you |
36 | that it will not switch between threads unless necessary, at |
36 | that it will not switch between threads unless necessary, at |
37 | easily-identified points in your program, so locking and parallel access |
37 | easily-identified points in your program, so locking and parallel access |
38 | are rarely an issue, making thread programming much safer and easier |
38 | are rarely an issue, making thread programming much safer and easier |
39 | than using other thread models. |
39 | than using other thread models. |
40 | |
40 | |
41 | Unlike the so-called "Perl threads" (which are not actually real threads |
41 | Unlike the so-called "Perl threads" (which are not actually real threads |
42 | but only the windows process emulation ported to unix), Coro provides a |
42 | but only the windows process emulation (see section of same name for |
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43 | more details) ported to unix, and as such act as processes), Coro |
43 | full shared address space, which makes communication between threads |
44 | provides a full shared address space, which makes communication between |
44 | very easy. And threads are fast, too: disabling the Windows process |
45 | threads very easy. And Coro's threads are fast, too: disabling the |
45 | emulation code in your perl and using Coro can easily result in a two to |
46 | Windows process emulation code in your perl and using Coro can easily |
46 | four times speed increase for your programs. |
47 | result in a two to four times speed increase for your programs. A |
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48 | parallel matrix multiplication benchmark runs over 300 times faster on a |
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49 | single core than perl's pseudo-threads on a quad core using all four |
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50 | cores. |
47 | |
51 | |
48 | Coro achieves that by supporting multiple running interpreters that |
52 | Coro achieves that by supporting multiple running interpreters that |
49 | share data, which is especially useful to code pseudo-parallel processes |
53 | share data, which is especially useful to code pseudo-parallel processes |
50 | and for event-based programming, such as multiple HTTP-GET requests |
54 | and for event-based programming, such as multiple HTTP-GET requests |
51 | running concurrently. See Coro::AnyEvent to learn more on how to |
55 | running concurrently. See Coro::AnyEvent to learn more on how to |
52 | integrate Coro into an event-based environment. |
56 | integrate Coro into an event-based environment. |
53 | |
57 | |
54 | In this module, a thread is defined as "callchain + lexical variables + |
58 | In this module, a thread is defined as "callchain + lexical variables + |
55 | @_ + $_ + $@ + $/ + C stack), that is, a thread has its own callchain, |
59 | some package variables + C stack), that is, a thread has its own |
56 | its own set of lexicals and its own set of perls most important global |
60 | callchain, its own set of lexicals and its own set of perls most |
57 | variables (see Coro::State for more configuration and background info). |
61 | important global variables (see Coro::State for more configuration and |
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62 | background info). |
58 | |
63 | |
59 | See also the "SEE ALSO" section at the end of this document - the Coro |
64 | See also the "SEE ALSO" section at the end of this document - the Coro |
60 | module family is quite large. |
65 | module family is quite large. |
61 | |
66 | |
62 | GLOBAL VARIABLES |
67 | GLOBAL VARIABLES |
63 | $Coro::main |
68 | $Coro::main |
64 | This variable stores the coroutine object that represents the main |
69 | This variable stores the Coro object that represents the main |
65 | program. While you cna "ready" it and do most other things you can |
70 | program. While you cna "ready" it and do most other things you can |
66 | do to coroutines, it is mainly useful to compare again |
71 | do to coro, it is mainly useful to compare again $Coro::current, to |
67 | $Coro::current, to see whether you are running in the main program |
72 | see whether you are running in the main program or not. |
68 | or not. |
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69 | |
73 | |
70 | $Coro::current |
74 | $Coro::current |
71 | The coroutine object representing the current coroutine (the last |
75 | The Coro object representing the current coro (the last coro that |
72 | coroutine that the Coro scheduler switched to). The initial value is |
76 | the Coro scheduler switched to). The initial value is $Coro::main |
73 | $Coro::main (of course). |
77 | (of course). |
74 | |
78 | |
75 | This variable is strictly *read-only*. You can take copies of the |
79 | This variable is strictly *read-only*. You can take copies of the |
76 | value stored in it and use it as any other coroutine object, but you |
80 | value stored in it and use it as any other Coro object, but you must |
77 | must not otherwise modify the variable itself. |
81 | not otherwise modify the variable itself. |
78 | |
82 | |
79 | $Coro::idle |
83 | $Coro::idle |
80 | This variable is mainly useful to integrate Coro into event loops. |
84 | This variable is mainly useful to integrate Coro into event loops. |
81 | It is usually better to rely on Coro::AnyEvent or Coro::EV, as this |
85 | It is usually better to rely on Coro::AnyEvent or Coro::EV, as this |
82 | is pretty low-level functionality. |
86 | is pretty low-level functionality. |
83 | |
87 | |
84 | This variable stores either a coroutine or a callback. |
88 | This variable stores a Coro object that is put into the ready queue |
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89 | when there are no other ready threads (without invoking any ready |
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90 | hooks). |
85 | |
91 | |
86 | If it is a callback, the it is called whenever the scheduler finds |
92 | The default implementation dies with "FATAL: deadlock detected.", |
87 | no ready coroutines to run. The default implementation prints |
93 | followed by a thread listing, because the program has no other way |
88 | "FATAL: deadlock detected" and exits, because the program has no |
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89 | other way to continue. |
94 | to continue. |
90 | |
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91 | If it is a coroutine object, then this object will be readied |
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92 | (without invoking any ready hooks, however) when the scheduler finds |
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93 | no other ready coroutines to run. |
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94 | |
95 | |
95 | This hook is overwritten by modules such as "Coro::EV" and |
96 | This hook is overwritten by modules such as "Coro::EV" and |
96 | "Coro::AnyEvent" to wait on an external event that hopefully wake up |
97 | "Coro::AnyEvent" to wait on an external event that hopefully wake up |
97 | a coroutine so the scheduler can run it. |
98 | a coro so the scheduler can run it. |
98 | |
99 | |
99 | Note that the callback *must not*, under any circumstances, block |
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100 | the current coroutine. Normally, this is achieved by having an "idle |
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101 | coroutine" that calls the event loop and then blocks again, and then |
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102 | readying that coroutine in the idle handler, or by simply placing |
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103 | the idle coroutine in this variable. |
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104 | |
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105 | See Coro::Event or Coro::AnyEvent for examples of using this |
100 | See Coro::EV or Coro::AnyEvent for examples of using this technique. |
106 | technique. |
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107 | |
101 | |
108 | Please note that if your callback recursively invokes perl (e.g. for |
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109 | event handlers), then it must be prepared to be called recursively |
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110 | itself. |
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111 | |
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112 | SIMPLE COROUTINE CREATION |
102 | SIMPLE CORO CREATION |
113 | async { ... } [@args...] |
103 | async { ... } [@args...] |
114 | Create a new coroutine and return its coroutine object (usually |
104 | Create a new coro and return its Coro object (usually unused). The |
115 | unused). The coroutine will be put into the ready queue, so it will |
105 | coro will be put into the ready queue, so it will start running |
116 | start running automatically on the next scheduler run. |
106 | automatically on the next scheduler run. |
117 | |
107 | |
118 | The first argument is a codeblock/closure that should be executed in |
108 | The first argument is a codeblock/closure that should be executed in |
119 | the coroutine. When it returns argument returns the coroutine is |
109 | the coro. When it returns argument returns the coro is automatically |
120 | automatically terminated. |
110 | terminated. |
121 | |
111 | |
122 | The remaining arguments are passed as arguments to the closure. |
112 | The remaining arguments are passed as arguments to the closure. |
123 | |
113 | |
124 | See the "Coro::State::new" constructor for info about the coroutine |
114 | See the "Coro::State::new" constructor for info about the coro |
125 | environment in which coroutines are executed. |
115 | environment in which coro are executed. |
126 | |
116 | |
127 | Calling "exit" in a coroutine will do the same as calling exit |
117 | Calling "exit" in a coro will do the same as calling exit outside |
128 | outside the coroutine. Likewise, when the coroutine dies, the |
118 | the coro. Likewise, when the coro dies, the program will exit, just |
129 | program will exit, just as it would in the main program. |
119 | as it would in the main program. |
130 | |
120 | |
131 | If you do not want that, you can provide a default "die" handler, or |
121 | If you do not want that, you can provide a default "die" handler, or |
132 | simply avoid dieing (by use of "eval"). |
122 | simply avoid dieing (by use of "eval"). |
133 | |
123 | |
134 | Example: Create a new coroutine that just prints its arguments. |
124 | Example: Create a new coro that just prints its arguments. |
135 | |
125 | |
136 | async { |
126 | async { |
137 | print "@_\n"; |
127 | print "@_\n"; |
138 | } 1,2,3,4; |
128 | } 1,2,3,4; |
139 | |
129 | |
140 | async_pool { ... } [@args...] |
130 | async_pool { ... } [@args...] |
141 | Similar to "async", but uses a coroutine pool, so you should not |
131 | Similar to "async", but uses a coro pool, so you should not call |
142 | call terminate or join on it (although you are allowed to), and you |
132 | terminate or join on it (although you are allowed to), and you get a |
143 | get a coroutine that might have executed other code already (which |
133 | coro that might have executed other code already (which can be good |
144 | can be good or bad :). |
134 | or bad :). |
145 | |
135 | |
146 | On the plus side, this function is about twice as fast as creating |
136 | On the plus side, this function is about twice as fast as creating |
147 | (and destroying) a completely new coroutine, so if you need a lot of |
137 | (and destroying) a completely new coro, so if you need a lot of |
148 | generic coroutines in quick successsion, use "async_pool", not |
138 | generic coros in quick successsion, use "async_pool", not "async". |
149 | "async". |
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150 | |
139 | |
151 | The code block is executed in an "eval" context and a warning will |
140 | The code block is executed in an "eval" context and a warning will |
152 | be issued in case of an exception instead of terminating the |
141 | be issued in case of an exception instead of terminating the |
153 | program, as "async" does. As the coroutine is being reused, stuff |
142 | program, as "async" does. As the coro is being reused, stuff like |
154 | like "on_destroy" will not work in the expected way, unless you call |
143 | "on_destroy" will not work in the expected way, unless you call |
155 | terminate or cancel, which somehow defeats the purpose of pooling |
144 | terminate or cancel, which somehow defeats the purpose of pooling |
156 | (but is fine in the exceptional case). |
145 | (but is fine in the exceptional case). |
157 | |
146 | |
158 | The priority will be reset to 0 after each run, tracing will be |
147 | The priority will be reset to 0 after each run, tracing will be |
159 | disabled, the description will be reset and the default output |
148 | disabled, the description will be reset and the default output |
160 | filehandle gets restored, so you can change all these. Otherwise the |
149 | filehandle gets restored, so you can change all these. Otherwise the |
161 | coroutine will be re-used "as-is": most notably if you change other |
150 | coro will be re-used "as-is": most notably if you change other |
162 | per-coroutine global stuff such as $/ you *must needs* revert that |
151 | per-coro global stuff such as $/ you *must needs* revert that |
163 | change, which is most simply done by using local as in: "local $/". |
152 | change, which is most simply done by using local as in: "local $/". |
164 | |
153 | |
165 | The idle pool size is limited to 8 idle coroutines (this can be |
154 | The idle pool size is limited to 8 idle coros (this can be adjusted |
166 | adjusted by changing $Coro::POOL_SIZE), but there can be as many |
155 | by changing $Coro::POOL_SIZE), but there can be as many non-idle |
167 | non-idle coros as required. |
156 | coros as required. |
168 | |
157 | |
169 | If you are concerned about pooled coroutines growing a lot because a |
158 | If you are concerned about pooled coros growing a lot because a |
170 | single "async_pool" used a lot of stackspace you can e.g. |
159 | single "async_pool" used a lot of stackspace you can e.g. |
171 | "async_pool { terminate }" once per second or so to slowly replenish |
160 | "async_pool { terminate }" once per second or so to slowly replenish |
172 | the pool. In addition to that, when the stacks used by a handler |
161 | the pool. In addition to that, when the stacks used by a handler |
173 | grows larger than 32kb (adjustable via $Coro::POOL_RSS) it will also |
162 | grows larger than 32kb (adjustable via $Coro::POOL_RSS) it will also |
174 | be destroyed. |
163 | be destroyed. |
175 | |
164 | |
176 | STATIC METHODS |
165 | STATIC METHODS |
177 | Static methods are actually functions that implicitly operate on the |
166 | Static methods are actually functions that implicitly operate on the |
178 | current coroutine. |
167 | current coro. |
179 | |
168 | |
180 | schedule |
169 | schedule |
181 | Calls the scheduler. The scheduler will find the next coroutine that |
170 | Calls the scheduler. The scheduler will find the next coro that is |
182 | is to be run from the ready queue and switches to it. The next |
171 | to be run from the ready queue and switches to it. The next coro to |
183 | coroutine to be run is simply the one with the highest priority that |
172 | be run is simply the one with the highest priority that is longest |
184 | is longest in its ready queue. If there is no coroutine ready, it |
173 | in its ready queue. If there is no coro ready, it will call the |
185 | will clal the $Coro::idle hook. |
174 | $Coro::idle hook. |
186 | |
175 | |
187 | Please note that the current coroutine will *not* be put into the |
176 | Please note that the current coro will *not* be put into the ready |
188 | ready queue, so calling this function usually means you will never |
177 | queue, so calling this function usually means you will never be |
189 | be called again unless something else (e.g. an event handler) calls |
178 | called again unless something else (e.g. an event handler) calls |
190 | "->ready", thus waking you up. |
179 | "->ready", thus waking you up. |
191 | |
180 | |
192 | This makes "schedule" *the* generic method to use to block the |
181 | This makes "schedule" *the* generic method to use to block the |
193 | current coroutine and wait for events: first you remember the |
182 | current coro and wait for events: first you remember the current |
194 | current coroutine in a variable, then arrange for some callback of |
183 | coro in a variable, then arrange for some callback of yours to call |
195 | yours to call "->ready" on that once some event happens, and last |
184 | "->ready" on that once some event happens, and last you call |
196 | you call "schedule" to put yourself to sleep. Note that a lot of |
185 | "schedule" to put yourself to sleep. Note that a lot of things can |
197 | things can wake your coroutine up, so you need to check whether the |
186 | wake your coro up, so you need to check whether the event indeed |
198 | event indeed happened, e.g. by storing the status in a variable. |
187 | happened, e.g. by storing the status in a variable. |
199 | |
188 | |
200 | See HOW TO WAIT FOR A CALLBACK, below, for some ways to wait for |
189 | See HOW TO WAIT FOR A CALLBACK, below, for some ways to wait for |
201 | callbacks. |
190 | callbacks. |
202 | |
191 | |
203 | cede |
192 | cede |
204 | "Cede" to other coroutines. This function puts the current coroutine |
193 | "Cede" to other coros. This function puts the current coro into the |
205 | into the ready queue and calls "schedule", which has the effect of |
194 | ready queue and calls "schedule", which has the effect of giving up |
206 | giving up the current "timeslice" to other coroutines of the same or |
195 | the current "timeslice" to other coros of the same or higher |
207 | higher priority. Once your coroutine gets its turn again it will |
196 | priority. Once your coro gets its turn again it will automatically |
208 | automatically be resumed. |
197 | be resumed. |
209 | |
198 | |
210 | This function is often called "yield" in other languages. |
199 | This function is often called "yield" in other languages. |
211 | |
200 | |
212 | Coro::cede_notself |
201 | Coro::cede_notself |
213 | Works like cede, but is not exported by default and will cede to |
202 | Works like cede, but is not exported by default and will cede to |
214 | *any* coroutine, regardless of priority. This is useful sometimes to |
203 | *any* coro, regardless of priority. This is useful sometimes to |
215 | ensure progress is made. |
204 | ensure progress is made. |
216 | |
205 | |
217 | terminate [arg...] |
206 | terminate [arg...] |
218 | Terminates the current coroutine with the given status values (see |
207 | Terminates the current coro with the given status values (see |
219 | cancel). |
208 | cancel). |
220 | |
209 | |
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210 | Coro::on_enter BLOCK, Coro::on_leave BLOCK |
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211 | These function install enter and leave winders in the current scope. |
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212 | The enter block will be executed when on_enter is called and |
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213 | whenever the current coro is re-entered by the scheduler, while the |
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214 | leave block is executed whenever the current coro is blocked by the |
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215 | scheduler, and also when the containing scope is exited (by whatever |
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216 | means, be it exit, die, last etc.). |
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217 | |
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218 | *Neither invoking the scheduler, nor exceptions, are allowed within |
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219 | those BLOCKs*. That means: do not even think about calling "die" |
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220 | without an eval, and do not even think of entering the scheduler in |
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221 | any way. |
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222 | |
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223 | Since both BLOCKs are tied to the current scope, they will |
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224 | automatically be removed when the current scope exits. |
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225 | |
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226 | These functions implement the same concept as "dynamic-wind" in |
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227 | scheme does, and are useful when you want to localise some resource |
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228 | to a specific coro. |
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229 | |
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230 | They slow down thread switching considerably for coros that use them |
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231 | (about 40% for a BLOCK with a single assignment, so thread switching |
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232 | is still reasonably fast if the handlers are fast). |
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233 | |
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234 | These functions are best understood by an example: The following |
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235 | function will change the current timezone to |
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236 | "Antarctica/South_Pole", which requires a call to "tzset", but by |
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237 | using "on_enter" and "on_leave", which remember/change the current |
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238 | timezone and restore the previous value, respectively, the timezone |
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239 | is only changed for the coro that installed those handlers. |
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240 | |
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241 | use POSIX qw(tzset); |
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242 | |
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243 | async { |
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244 | my $old_tz; # store outside TZ value here |
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245 | |
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246 | Coro::on_enter { |
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247 | $old_tz = $ENV{TZ}; # remember the old value |
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248 | |
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249 | $ENV{TZ} = "Antarctica/South_Pole"; |
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250 | tzset; # enable new value |
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251 | }; |
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252 | |
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253 | Coro::on_leave { |
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254 | $ENV{TZ} = $old_tz; |
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255 | tzset; # restore old value |
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256 | }; |
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257 | |
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258 | # at this place, the timezone is Antarctica/South_Pole, |
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259 | # without disturbing the TZ of any other coro. |
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260 | }; |
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261 | |
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262 | This can be used to localise about any resource (locale, uid, |
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263 | current working directory etc.) to a block, despite the existance of |
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264 | other coros. |
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265 | |
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266 | Another interesting example implements time-sliced multitasking |
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267 | using interval timers (this could obviously be optimised, but does |
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268 | the job): |
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269 | |
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270 | # "timeslice" the given block |
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271 | sub timeslice(&) { |
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272 | use Time::HiRes (); |
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273 | |
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274 | Coro::on_enter { |
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275 | # on entering the thread, we set an VTALRM handler to cede |
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276 | $SIG{VTALRM} = sub { cede }; |
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277 | # and then start the interval timer |
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278 | Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0.01, 0.01; |
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279 | }; |
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280 | Coro::on_leave { |
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281 | # on leaving the thread, we stop the interval timer again |
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282 | Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0, 0; |
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283 | }; |
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284 | |
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285 | &{+shift}; |
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286 | } |
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287 | |
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288 | # use like this: |
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289 | timeslice { |
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290 | # The following is an endless loop that would normally |
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291 | # monopolise the process. Since it runs in a timesliced |
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292 | # environment, it will regularly cede to other threads. |
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293 | while () { } |
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294 | }; |
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295 | |
221 | killall |
296 | killall |
222 | Kills/terminates/cancels all coroutines except the currently running |
297 | Kills/terminates/cancels all coros except the currently running one. |
223 | one. This is useful after a fork, either in the child or the parent, |
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224 | as usually only one of them should inherit the running coroutines. |
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225 | |
298 | |
226 | Note that while this will try to free some of the main programs |
299 | Note that while this will try to free some of the main interpreter |
227 | resources, you cannot free all of them, so if a coroutine that is |
300 | resources if the calling coro isn't the main coro, but one cannot |
228 | not the main program calls this function, there will be some |
301 | free all of them, so if a coro that is not the main coro calls this |
229 | one-time resource leak. |
302 | function, there will be some one-time resource leak. |
230 | |
303 | |
231 | COROUTINE OBJECT METHODS |
304 | CORO OBJECT METHODS |
232 | These are the methods you can call on coroutine objects (or to create |
305 | These are the methods you can call on coro objects (or to create them). |
233 | them). |
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234 | |
306 | |
235 | new Coro \&sub [, @args...] |
307 | new Coro \&sub [, @args...] |
236 | Create a new coroutine and return it. When the sub returns, the |
308 | Create a new coro and return it. When the sub returns, the coro |
237 | coroutine automatically terminates as if "terminate" with the |
309 | automatically terminates as if "terminate" with the returned values |
238 | returned values were called. To make the coroutine run you must |
310 | were called. To make the coro run you must first put it into the |
239 | first put it into the ready queue by calling the ready method. |
311 | ready queue by calling the ready method. |
240 | |
312 | |
241 | See "async" and "Coro::State::new" for additional info about the |
313 | See "async" and "Coro::State::new" for additional info about the |
242 | coroutine environment. |
314 | coro environment. |
243 | |
315 | |
244 | $success = $coroutine->ready |
316 | $success = $coro->ready |
245 | Put the given coroutine into the end of its ready queue (there is |
317 | Put the given coro into the end of its ready queue (there is one |
246 | one queue for each priority) and return true. If the coroutine is |
318 | queue for each priority) and return true. If the coro is already in |
247 | already in the ready queue, do nothing and return false. |
319 | the ready queue, do nothing and return false. |
248 | |
320 | |
249 | This ensures that the scheduler will resume this coroutine |
321 | This ensures that the scheduler will resume this coro automatically |
250 | automatically once all the coroutines of higher priority and all |
322 | once all the coro of higher priority and all coro of the same |
251 | coroutines of the same priority that were put into the ready queue |
323 | priority that were put into the ready queue earlier have been |
252 | earlier have been resumed. |
324 | resumed. |
253 | |
325 | |
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326 | $coro->suspend |
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327 | Suspends the specified coro. A suspended coro works just like any |
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328 | other coro, except that the scheduler will not select a suspended |
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329 | coro for execution. |
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330 | |
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331 | Suspending a coro can be useful when you want to keep the coro from |
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332 | running, but you don't want to destroy it, or when you want to |
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333 | temporarily freeze a coro (e.g. for debugging) to resume it later. |
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334 | |
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335 | A scenario for the former would be to suspend all (other) coros |
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336 | after a fork and keep them alive, so their destructors aren't |
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337 | called, but new coros can be created. |
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338 | |
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339 | $coro->resume |
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340 | If the specified coro was suspended, it will be resumed. Note that |
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341 | when the coro was in the ready queue when it was suspended, it might |
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342 | have been unreadied by the scheduler, so an activation might have |
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343 | been lost. |
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344 | |
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345 | To avoid this, it is best to put a suspended coro into the ready |
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346 | queue unconditionally, as every synchronisation mechanism must |
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347 | protect itself against spurious wakeups, and the one in the Coro |
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348 | family certainly do that. |
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349 | |
254 | $is_ready = $coroutine->is_ready |
350 | $is_ready = $coro->is_ready |
255 | Return whether the coroutine is currently the ready queue or not, |
351 | Returns true iff the Coro object is in the ready queue. Unless the |
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352 | Coro object gets destroyed, it will eventually be scheduled by the |
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353 | scheduler. |
256 | |
354 | |
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355 | $is_running = $coro->is_running |
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356 | Returns true iff the Coro object is currently running. Only one Coro |
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357 | object can ever be in the running state (but it currently is |
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358 | possible to have multiple running Coro::States). |
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359 | |
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360 | $is_suspended = $coro->is_suspended |
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361 | Returns true iff this Coro object has been suspended. Suspended |
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362 | Coros will not ever be scheduled. |
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363 | |
257 | $coroutine->cancel (arg...) |
364 | $coro->cancel (arg...) |
258 | Terminates the given coroutine and makes it return the given |
365 | Terminates the given Coro and makes it return the given arguments as |
259 | arguments as status (default: the empty list). Never returns if the |
366 | status (default: the empty list). Never returns if the Coro is the |
260 | coroutine is the current coroutine. |
367 | current Coro. |
261 | |
368 | |
262 | $coroutine->schedule_to |
369 | $coro->schedule_to |
263 | Puts the current coroutine to sleep (like "Coro::schedule"), but |
370 | Puts the current coro to sleep (like "Coro::schedule"), but instead |
264 | instead of continuing with the next coro from the ready queue, |
371 | of continuing with the next coro from the ready queue, always switch |
265 | always switch to the given coroutine object (regardless of priority |
372 | to the given coro object (regardless of priority etc.). The |
266 | etc.). The readyness state of that coroutine isn't changed. |
373 | readyness state of that coro isn't changed. |
267 | |
374 | |
268 | This is an advanced method for special cases - I'd love to hear |
375 | This is an advanced method for special cases - I'd love to hear |
269 | about any uses for this one. |
376 | about any uses for this one. |
270 | |
377 | |
271 | $coroutine->cede_to |
378 | $coro->cede_to |
272 | Like "schedule_to", but puts the current coroutine into the ready |
379 | Like "schedule_to", but puts the current coro into the ready queue. |
273 | queue. This has the effect of temporarily switching to the given |
380 | This has the effect of temporarily switching to the given coro, and |
274 | coroutine, and continuing some time later. |
381 | continuing some time later. |
275 | |
382 | |
276 | This is an advanced method for special cases - I'd love to hear |
383 | This is an advanced method for special cases - I'd love to hear |
277 | about any uses for this one. |
384 | about any uses for this one. |
278 | |
385 | |
279 | $coroutine->throw ([$scalar]) |
386 | $coro->throw ([$scalar]) |
280 | If $throw is specified and defined, it will be thrown as an |
387 | If $throw is specified and defined, it will be thrown as an |
281 | exception inside the coroutine at the next convenient point in time. |
388 | exception inside the coro at the next convenient point in time. |
282 | Otherwise clears the exception object. |
389 | Otherwise clears the exception object. |
283 | |
390 | |
284 | Coro will check for the exception each time a schedule-like-function |
391 | Coro will check for the exception each time a schedule-like-function |
285 | returns, i.e. after each "schedule", "cede", |
392 | returns, i.e. after each "schedule", "cede", |
286 | "Coro::Semaphore->down", "Coro::Handle->readable" and so on. Most of |
393 | "Coro::Semaphore->down", "Coro::Handle->readable" and so on. Most of |
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289 | |
396 | |
290 | The exception object will be thrown "as is" with the specified |
397 | The exception object will be thrown "as is" with the specified |
291 | scalar in $@, i.e. if it is a string, no line number or newline will |
398 | scalar in $@, i.e. if it is a string, no line number or newline will |
292 | be appended (unlike with "die"). |
399 | be appended (unlike with "die"). |
293 | |
400 | |
294 | This can be used as a softer means than "cancel" to ask a coroutine |
401 | This can be used as a softer means than "cancel" to ask a coro to |
295 | to end itself, although there is no guarantee that the exception |
402 | end itself, although there is no guarantee that the exception will |
296 | will lead to termination, and if the exception isn't caught it might |
403 | lead to termination, and if the exception isn't caught it might well |
297 | well end the whole program. |
404 | end the whole program. |
298 | |
405 | |
299 | You might also think of "throw" as being the moral equivalent of |
406 | You might also think of "throw" as being the moral equivalent of |
300 | "kill"ing a coroutine with a signal (in this case, a scalar). |
407 | "kill"ing a coro with a signal (in this case, a scalar). |
301 | |
408 | |
302 | $coroutine->join |
409 | $coro->join |
303 | Wait until the coroutine terminates and return any values given to |
410 | Wait until the coro terminates and return any values given to the |
304 | the "terminate" or "cancel" functions. "join" can be called |
411 | "terminate" or "cancel" functions. "join" can be called concurrently |
305 | concurrently from multiple coroutines, and all will be resumed and |
412 | from multiple coro, and all will be resumed and given the status |
306 | given the status return once the $coroutine terminates. |
413 | return once the $coro terminates. |
307 | |
414 | |
308 | $coroutine->on_destroy (\&cb) |
415 | $coro->on_destroy (\&cb) |
309 | Registers a callback that is called when this coroutine gets |
416 | Registers a callback that is called when this coro thread gets |
310 | destroyed, but before it is joined. The callback gets passed the |
417 | destroyed, but before it is joined. The callback gets passed the |
311 | terminate arguments, if any, and *must not* die, under any |
418 | terminate arguments, if any, and *must not* die, under any |
312 | circumstances. |
419 | circumstances. |
313 | |
420 | |
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421 | There can be any number of "on_destroy" callbacks per coro. |
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422 | |
314 | $oldprio = $coroutine->prio ($newprio) |
423 | $oldprio = $coro->prio ($newprio) |
315 | Sets (or gets, if the argument is missing) the priority of the |
424 | Sets (or gets, if the argument is missing) the priority of the coro |
316 | coroutine. Higher priority coroutines get run before lower priority |
425 | thread. Higher priority coro get run before lower priority coros. |
317 | coroutines. Priorities are small signed integers (currently -4 .. |
426 | Priorities are small signed integers (currently -4 .. +3), that you |
318 | +3), that you can refer to using PRIO_xxx constants (use the import |
427 | can refer to using PRIO_xxx constants (use the import tag :prio to |
319 | tag :prio to get then): |
428 | get then): |
320 | |
429 | |
321 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
430 | PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
322 | 3 > 1 > 0 > -1 > -3 > -4 |
431 | 3 > 1 > 0 > -1 > -3 > -4 |
323 | |
432 | |
324 | # set priority to HIGH |
433 | # set priority to HIGH |
325 | current->prio(PRIO_HIGH); |
434 | current->prio (PRIO_HIGH); |
326 | |
435 | |
327 | The idle coroutine ($Coro::idle) always has a lower priority than |
436 | The idle coro thread ($Coro::idle) always has a lower priority than |
328 | any existing coroutine. |
437 | any existing coro. |
329 | |
438 | |
330 | Changing the priority of the current coroutine will take effect |
439 | Changing the priority of the current coro will take effect |
331 | immediately, but changing the priority of coroutines in the ready |
440 | immediately, but changing the priority of a coro in the ready queue |
332 | queue (but not running) will only take effect after the next |
441 | (but not running) will only take effect after the next schedule (of |
333 | schedule (of that coroutine). This is a bug that will be fixed in |
442 | that coro). This is a bug that will be fixed in some future version. |
334 | some future version. |
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335 | |
443 | |
336 | $newprio = $coroutine->nice ($change) |
444 | $newprio = $coro->nice ($change) |
337 | Similar to "prio", but subtract the given value from the priority |
445 | Similar to "prio", but subtract the given value from the priority |
338 | (i.e. higher values mean lower priority, just as in unix). |
446 | (i.e. higher values mean lower priority, just as in UNIX's nice |
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447 | command). |
339 | |
448 | |
340 | $olddesc = $coroutine->desc ($newdesc) |
449 | $olddesc = $coro->desc ($newdesc) |
341 | Sets (or gets in case the argument is missing) the description for |
450 | Sets (or gets in case the argument is missing) the description for |
342 | this coroutine. This is just a free-form string you can associate |
451 | this coro thread. This is just a free-form string you can associate |
343 | with a coroutine. |
452 | with a coro. |
344 | |
453 | |
345 | This method simply sets the "$coroutine->{desc}" member to the given |
454 | This method simply sets the "$coro->{desc}" member to the given |
346 | string. You can modify this member directly if you wish. |
455 | string. You can modify this member directly if you wish, and in |
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456 | fact, this is often preferred to indicate major processing states |
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457 | that cna then be seen for example in a Coro::Debug session: |
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458 | |
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459 | sub my_long_function { |
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460 | local $Coro::current->{desc} = "now in my_long_function"; |
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461 | ... |
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462 | $Coro::current->{desc} = "my_long_function: phase 1"; |
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463 | ... |
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464 | $Coro::current->{desc} = "my_long_function: phase 2"; |
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465 | ... |
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466 | } |
347 | |
467 | |
348 | GLOBAL FUNCTIONS |
468 | GLOBAL FUNCTIONS |
349 | Coro::nready |
469 | Coro::nready |
350 | Returns the number of coroutines that are currently in the ready |
470 | Returns the number of coro that are currently in the ready state, |
351 | state, i.e. that can be switched to by calling "schedule" directory |
471 | i.e. that can be switched to by calling "schedule" directory or |
352 | or indirectly. The value 0 means that the only runnable coroutine is |
472 | indirectly. The value 0 means that the only runnable coro is the |
353 | the currently running one, so "cede" would have no effect, and |
473 | currently running one, so "cede" would have no effect, and |
354 | "schedule" would cause a deadlock unless there is an idle handler |
474 | "schedule" would cause a deadlock unless there is an idle handler |
355 | that wakes up some coroutines. |
475 | that wakes up some coro. |
356 | |
476 | |
357 | my $guard = Coro::guard { ... } |
477 | my $guard = Coro::guard { ... } |
358 | This creates and returns a guard object. Nothing happens until the |
478 | This function still exists, but is deprecated. Please use the |
359 | object gets destroyed, in which case the codeblock given as argument |
479 | "Guard::guard" function instead. |
360 | will be executed. This is useful to free locks or other resources in |
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361 | case of a runtime error or when the coroutine gets canceled, as in |
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362 | both cases the guard block will be executed. The guard object |
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363 | supports only one method, "->cancel", which will keep the codeblock |
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364 | from being executed. |
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365 | |
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366 | Example: set some flag and clear it again when the coroutine gets |
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367 | canceled or the function returns: |
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368 | |
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369 | sub do_something { |
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370 | my $guard = Coro::guard { $busy = 0 }; |
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371 | $busy = 1; |
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372 | |
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373 | # do something that requires $busy to be true |
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374 | } |
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375 | |
480 | |
376 | unblock_sub { ... } |
481 | unblock_sub { ... } |
377 | This utility function takes a BLOCK or code reference and "unblocks" |
482 | This utility function takes a BLOCK or code reference and "unblocks" |
378 | it, returning a new coderef. Unblocking means that calling the new |
483 | it, returning a new coderef. Unblocking means that calling the new |
379 | coderef will return immediately without blocking, returning nothing, |
484 | coderef will return immediately without blocking, returning nothing, |
380 | while the original code ref will be called (with parameters) from |
485 | while the original code ref will be called (with parameters) from |
381 | within another coroutine. |
486 | within another coro. |
382 | |
487 | |
383 | The reason this function exists is that many event libraries (such |
488 | The reason this function exists is that many event libraries (such |
384 | as the venerable Event module) are not coroutine-safe (a weaker form |
489 | as the venerable Event module) are not thread-safe (a weaker form of |
385 | of reentrancy). This means you must not block within event |
490 | reentrancy). This means you must not block within event callbacks, |
386 | callbacks, otherwise you might suffer from crashes or worse. The |
491 | otherwise you might suffer from crashes or worse. The only event |
387 | only event library currently known that is safe to use without |
492 | library currently known that is safe to use without "unblock_sub" is |
388 | "unblock_sub" is EV. |
493 | EV (but you might still run into deadlocks if all event loops are |
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494 | blocked). |
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495 | |
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496 | Coro will try to catch you when you block in the event loop |
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497 | ("FATAL:$Coro::IDLE blocked itself"), but this is just best effort |
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498 | and only works when you do not run your own event loop. |
389 | |
499 | |
390 | This function allows your callbacks to block by executing them in |
500 | This function allows your callbacks to block by executing them in |
391 | another coroutine where it is safe to block. One example where |
501 | another coro where it is safe to block. One example where blocking |
392 | blocking is handy is when you use the Coro::AIO functions to save |
502 | is handy is when you use the Coro::AIO functions to save results to |
393 | results to disk, for example. |
503 | disk, for example. |
394 | |
504 | |
395 | In short: simply use "unblock_sub { ... }" instead of "sub { ... }" |
505 | In short: simply use "unblock_sub { ... }" instead of "sub { ... }" |
396 | when creating event callbacks that want to block. |
506 | when creating event callbacks that want to block. |
397 | |
507 | |
398 | If your handler does not plan to block (e.g. simply sends a message |
508 | If your handler does not plan to block (e.g. simply sends a message |
399 | to another coroutine, or puts some other coroutine into the ready |
509 | to another coro, or puts some other coro into the ready queue), |
400 | queue), there is no reason to use "unblock_sub". |
510 | there is no reason to use "unblock_sub". |
401 | |
511 | |
402 | Note that you also need to use "unblock_sub" for any other callbacks |
512 | Note that you also need to use "unblock_sub" for any other callbacks |
403 | that are indirectly executed by any C-based event loop. For example, |
513 | that are indirectly executed by any C-based event loop. For example, |
404 | when you use a module that uses AnyEvent (and you use |
514 | when you use a module that uses AnyEvent (and you use |
405 | Coro::AnyEvent) and it provides callbacks that are the result of |
515 | Coro::AnyEvent) and it provides callbacks that are the result of |
406 | some event callback, then you must not block either, or use |
516 | some event callback, then you must not block either, or use |
407 | "unblock_sub". |
517 | "unblock_sub". |
408 | |
518 | |
409 | $cb = Coro::rouse_cb |
519 | $cb = rouse_cb |
410 | Create and return a "rouse callback". That's a code reference that, |
520 | Create and return a "rouse callback". That's a code reference that, |
411 | when called, will remember a copy of its arguments and notify the |
521 | when called, will remember a copy of its arguments and notify the |
412 | owner coroutine of the callback. |
522 | owner coro of the callback. |
413 | |
523 | |
414 | See the next function. |
524 | See the next function. |
415 | |
525 | |
416 | @args = Coro::rouse_wait [$cb] |
526 | @args = rouse_wait [$cb] |
417 | Wait for the specified rouse callback (or the last one that was |
527 | Wait for the specified rouse callback (or the last one that was |
418 | created in this coroutine). |
528 | created in this coro). |
419 | |
529 | |
420 | As soon as the callback is invoked (or when the callback was invoked |
530 | As soon as the callback is invoked (or when the callback was invoked |
421 | before "rouse_wait"), it will return the arguments originally passed |
531 | before "rouse_wait"), it will return the arguments originally passed |
422 | to the rouse callback. |
532 | to the rouse callback. In scalar context, that means you get the |
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533 | *last* argument, just as if "rouse_wait" had a "return ($a1, $a2, |
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534 | $a3...)" statement at the end. |
423 | |
535 | |
424 | See the section HOW TO WAIT FOR A CALLBACK for an actual usage |
536 | See the section HOW TO WAIT FOR A CALLBACK for an actual usage |
425 | example. |
537 | example. |
426 | |
538 | |
427 | HOW TO WAIT FOR A CALLBACK |
539 | HOW TO WAIT FOR A CALLBACK |
428 | It is very common for a coroutine to wait for some callback to be |
540 | It is very common for a coro to wait for some callback to be called. |
429 | called. This occurs naturally when you use coroutines in an otherwise |
541 | This occurs naturally when you use coro in an otherwise event-based |
430 | event-based program, or when you use event-based libraries. |
542 | program, or when you use event-based libraries. |
431 | |
543 | |
432 | These typically register a callback for some event, and call that |
544 | These typically register a callback for some event, and call that |
433 | callback when the event occured. In a coroutine, however, you typically |
545 | callback when the event occured. In a coro, however, you typically want |
434 | want to just wait for the event, simplyifying things. |
546 | to just wait for the event, simplyifying things. |
435 | |
547 | |
436 | For example "AnyEvent->child" registers a callback to be called when a |
548 | For example "AnyEvent->child" registers a callback to be called when a |
437 | specific child has exited: |
549 | specific child has exited: |
438 | |
550 | |
439 | my $child_watcher = AnyEvent->child (pid => $pid, cb => sub { ... }); |
551 | my $child_watcher = AnyEvent->child (pid => $pid, cb => sub { ... }); |
440 | |
552 | |
441 | But from withina coroutine, you often just want to write this: |
553 | But from within a coro, you often just want to write this: |
442 | |
554 | |
443 | my $status = wait_for_child $pid; |
555 | my $status = wait_for_child $pid; |
444 | |
556 | |
445 | Coro offers two functions specifically designed to make this easy, |
557 | Coro offers two functions specifically designed to make this easy, |
446 | "Coro::rouse_cb" and "Coro::rouse_wait". |
558 | "Coro::rouse_cb" and "Coro::rouse_wait". |
447 | |
559 | |
448 | The first function, "rouse_cb", generates and returns a callback that, |
560 | The first function, "rouse_cb", generates and returns a callback that, |
449 | when invoked, will save its arguments and notify the coroutine that |
561 | when invoked, will save its arguments and notify the coro that created |
450 | created the callback. |
562 | the callback. |
451 | |
563 | |
452 | The second function, "rouse_wait", waits for the callback to be called |
564 | The second function, "rouse_wait", waits for the callback to be called |
453 | (by calling "schedule" to go to sleep) and returns the arguments |
565 | (by calling "schedule" to go to sleep) and returns the arguments |
454 | originally passed to the callback. |
566 | originally passed to the callback. |
455 | |
567 | |
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469 | you can roll your own, using "schedule": |
581 | you can roll your own, using "schedule": |
470 | |
582 | |
471 | sub wait_for_child($) { |
583 | sub wait_for_child($) { |
472 | my ($pid) = @_; |
584 | my ($pid) = @_; |
473 | |
585 | |
474 | # store the current coroutine in $current, |
586 | # store the current coro in $current, |
475 | # and provide result variables for the closure passed to ->child |
587 | # and provide result variables for the closure passed to ->child |
476 | my $current = $Coro::current; |
588 | my $current = $Coro::current; |
477 | my ($done, $rstatus); |
589 | my ($done, $rstatus); |
478 | |
590 | |
479 | # pass a closure to ->child |
591 | # pass a closure to ->child |
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490 | |
602 | |
491 | BUGS/LIMITATIONS |
603 | BUGS/LIMITATIONS |
492 | fork with pthread backend |
604 | fork with pthread backend |
493 | When Coro is compiled using the pthread backend (which isn't |
605 | When Coro is compiled using the pthread backend (which isn't |
494 | recommended but required on many BSDs as their libcs are completely |
606 | recommended but required on many BSDs as their libcs are completely |
495 | broken), then coroutines will not survive a fork. There is no known |
607 | broken), then coro will not survive a fork. There is no known |
496 | workaround except to fix your libc and use a saner backend. |
608 | workaround except to fix your libc and use a saner backend. |
497 | |
609 | |
498 | perl process emulation ("threads") |
610 | perl process emulation ("threads") |
499 | This module is not perl-pseudo-thread-safe. You should only ever use |
611 | This module is not perl-pseudo-thread-safe. You should only ever use |
500 | this module from the first thread (this requirement might be removed |
612 | this module from the first thread (this requirement might be removed |
501 | in the future to allow per-thread schedulers, but Coro::State does |
613 | in the future to allow per-thread schedulers, but Coro::State does |
502 | not yet allow this). I recommend disabling thread support and using |
614 | not yet allow this). I recommend disabling thread support and using |
503 | processes, as having the windows process emulation enabled under |
615 | processes, as having the windows process emulation enabled under |
504 | unix roughly halves perl performance, even when not used. |
616 | unix roughly halves perl performance, even when not used. |
505 | |
617 | |
506 | coroutine switching not signal safe |
618 | coro switching is not signal safe |
507 | You must not switch to another coroutine from within a signal |
619 | You must not switch to another coro from within a signal handler |
508 | handler (only relevant with %SIG - most event libraries provide safe |
620 | (only relevant with %SIG - most event libraries provide safe |
509 | signals). |
621 | signals), *unless* you are sure you are not interrupting a Coro |
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622 | function. |
510 | |
623 | |
511 | That means you *MUST NOT* call any function that might "block" the |
624 | That means you *MUST NOT* call any function that might "block" the |
512 | current coroutine - "cede", "schedule" "Coro::Semaphore->down" or |
625 | current coro - "cede", "schedule" "Coro::Semaphore->down" or |
513 | anything that calls those. Everything else, including calling |
626 | anything that calls those. Everything else, including calling |
514 | "ready", works. |
627 | "ready", works. |
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628 | |
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629 | WINDOWS PROCESS EMULATION |
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630 | A great many people seem to be confused about ithreads (for example, |
|
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631 | Chip Salzenberg called me unintelligent, incapable, stupid and gullible, |
|
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632 | while in the same mail making rather confused statements about perl |
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633 | ithreads (for example, that memory or files would be shared), showing |
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634 | his lack of understanding of this area - if it is hard to understand for |
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635 | Chip, it is probably not obvious to everybody). |
|
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636 | |
|
|
637 | What follows is an ultra-condensed version of my talk about threads in |
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638 | scripting languages given on the perl workshop 2009: |
|
|
639 | |
|
|
640 | The so-called "ithreads" were originally implemented for two reasons: |
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641 | first, to (badly) emulate unix processes on native win32 perls, and |
|
|
642 | secondly, to replace the older, real thread model ("5.005-threads"). |
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643 | |
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644 | It does that by using threads instead of OS processes. The difference |
|
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645 | between processes and threads is that threads share memory (and other |
|
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646 | state, such as files) between threads within a single process, while |
|
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647 | processes do not share anything (at least not semantically). That means |
|
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648 | that modifications done by one thread are seen by others, while |
|
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649 | modifications by one process are not seen by other processes. |
|
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650 | |
|
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651 | The "ithreads" work exactly like that: when creating a new ithreads |
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652 | process, all state is copied (memory is copied physically, files and |
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653 | code is copied logically). Afterwards, it isolates all modifications. On |
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654 | UNIX, the same behaviour can be achieved by using operating system |
|
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655 | processes, except that UNIX typically uses hardware built into the |
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656 | system to do this efficiently, while the windows process emulation |
|
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657 | emulates this hardware in software (rather efficiently, but of course it |
|
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658 | is still much slower than dedicated hardware). |
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659 | |
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660 | As mentioned before, loading code, modifying code, modifying data |
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661 | structures and so on is only visible in the ithreads process doing the |
|
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662 | modification, not in other ithread processes within the same OS process. |
|
|
663 | |
|
|
664 | This is why "ithreads" do not implement threads for perl at all, only |
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665 | processes. What makes it so bad is that on non-windows platforms, you |
|
|
666 | can actually take advantage of custom hardware for this purpose (as |
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667 | evidenced by the forks module, which gives you the (i-) threads API, |
|
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668 | just much faster). |
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|
669 | |
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670 | Sharing data is in the i-threads model is done by transfering data |
|
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671 | structures between threads using copying semantics, which is very slow - |
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672 | shared data simply does not exist. Benchmarks using i-threads which are |
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673 | communication-intensive show extremely bad behaviour with i-threads (in |
|
|
674 | fact, so bad that Coro, which cannot take direct advantage of multiple |
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675 | CPUs, is often orders of magnitude faster because it shares data using |
|
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676 | real threads, refer to my talk for details). |
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677 | |
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678 | As summary, i-threads *use* threads to implement processes, while the |
|
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679 | compatible forks module *uses* processes to emulate, uhm, processes. |
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680 | I-threads slow down every perl program when enabled, and outside of |
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681 | windows, serve no (or little) practical purpose, but disadvantages every |
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682 | single-threaded Perl program. |
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683 | |
|
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684 | This is the reason that I try to avoid the name "ithreads", as it is |
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685 | misleading as it implies that it implements some kind of thread model |
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686 | for perl, and prefer the name "windows process emulation", which |
|
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687 | describes the actual use and behaviour of it much better. |
515 | |
688 | |
516 | SEE ALSO |
689 | SEE ALSO |
517 | Event-Loop integration: Coro::AnyEvent, Coro::EV, Coro::Event. |
690 | Event-Loop integration: Coro::AnyEvent, Coro::EV, Coro::Event. |
518 | |
691 | |
519 | Debugging: Coro::Debug. |
692 | Debugging: Coro::Debug. |