Mercurial > cpython-lru_cache-weakref
annotate Demo/threads/sync.py @ 80661:94de77bd0b4b 2.7
Issue #16194: document imp.load_dynamic problems
when read several extension modules from the same binary object file.
| author | Andrew Svetlov <andrew.svetlov@gmail.com> |
|---|---|
| date | Thu, 29 Nov 2012 19:51:28 +0200 |
| parents | 86e3943d0d5b |
| children |
| rev | line source |
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| 1637 | 1 # Defines classes that provide synchronization objects. Note that use of |
| 2 # this module requires that your Python support threads. | |
| 3 # | |
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4 # condition(lock=None) # a POSIX-like condition-variable object |
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5 # barrier(n) # an n-thread barrier |
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6 # event() # an event object |
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7 # semaphore(n=1) # a semaphore object, with initial count n |
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8 # mrsw() # a multiple-reader single-writer lock |
| 1637 | 9 # |
| 10 # CONDITIONS | |
| 11 # | |
| 12 # A condition object is created via | |
| 13 # import this_module | |
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14 # your_condition_object = this_module.condition(lock=None) |
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15 # |
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16 # As explained below, a condition object has a lock associated with it, |
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17 # used in the protocol to protect condition data. You can specify a |
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18 # lock to use in the constructor, else the constructor will allocate |
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19 # an anonymous lock for you. Specifying a lock explicitly can be useful |
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20 # when more than one condition keys off the same set of shared data. |
| 1637 | 21 # |
| 22 # Methods: | |
| 23 # .acquire() | |
| 24 # acquire the lock associated with the condition | |
| 25 # .release() | |
| 26 # release the lock associated with the condition | |
| 27 # .wait() | |
| 28 # block the thread until such time as some other thread does a | |
| 29 # .signal or .broadcast on the same condition, and release the | |
| 30 # lock associated with the condition. The lock associated with | |
| 31 # the condition MUST be in the acquired state at the time | |
| 32 # .wait is invoked. | |
| 33 # .signal() | |
| 34 # wake up exactly one thread (if any) that previously did a .wait | |
| 35 # on the condition; that thread will awaken with the lock associated | |
| 36 # with the condition in the acquired state. If no threads are | |
| 37 # .wait'ing, this is a nop. If more than one thread is .wait'ing on | |
| 38 # the condition, any of them may be awakened. | |
| 39 # .broadcast() | |
| 40 # wake up all threads (if any) that are .wait'ing on the condition; | |
| 41 # the threads are woken up serially, each with the lock in the | |
| 42 # acquired state, so should .release() as soon as possible. If no | |
| 43 # threads are .wait'ing, this is a nop. | |
| 44 # | |
| 45 # Note that if a thread does a .wait *while* a signal/broadcast is | |
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46 # in progress, it's guaranteeed to block until a subsequent |
| 1637 | 47 # signal/broadcast. |
| 48 # | |
| 49 # Secret feature: `broadcast' actually takes an integer argument, | |
| 50 # and will wake up exactly that many waiting threads (or the total | |
| 51 # number waiting, if that's less). Use of this is dubious, though, | |
| 52 # and probably won't be supported if this form of condition is | |
| 53 # reimplemented in C. | |
| 54 # | |
| 55 # DIFFERENCES FROM POSIX | |
| 56 # | |
| 57 # + A separate mutex is not needed to guard condition data. Instead, a | |
| 58 # condition object can (must) be .acquire'ed and .release'ed directly. | |
| 59 # This eliminates a common error in using POSIX conditions. | |
| 60 # | |
| 61 # + Because of implementation difficulties, a POSIX `signal' wakes up | |
| 62 # _at least_ one .wait'ing thread. Race conditions make it difficult | |
| 63 # to stop that. This implementation guarantees to wake up only one, | |
| 64 # but you probably shouldn't rely on that. | |
| 65 # | |
| 66 # PROTOCOL | |
| 67 # | |
| 68 # Condition objects are used to block threads until "some condition" is | |
| 69 # true. E.g., a thread may wish to wait until a producer pumps out data | |
| 70 # for it to consume, or a server may wish to wait until someone requests | |
| 71 # its services, or perhaps a whole bunch of threads want to wait until a | |
| 72 # preceding pass over the data is complete. Early models for conditions | |
| 73 # relied on some other thread figuring out when a blocked thread's | |
| 74 # condition was true, and made the other thread responsible both for | |
| 75 # waking up the blocked thread and guaranteeing that it woke up with all | |
| 76 # data in a correct state. This proved to be very delicate in practice, | |
| 77 # and gave conditions a bad name in some circles. | |
| 78 # | |
| 79 # The POSIX model addresses these problems by making a thread responsible | |
| 80 # for ensuring that its own state is correct when it wakes, and relies | |
| 81 # on a rigid protocol to make this easy; so long as you stick to the | |
| 82 # protocol, POSIX conditions are easy to "get right": | |
| 83 # | |
| 84 # A) The thread that's waiting for some arbitrarily-complex condition | |
| 85 # (ACC) to become true does: | |
| 86 # | |
| 87 # condition.acquire() | |
| 88 # while not (code to evaluate the ACC): | |
| 89 # condition.wait() | |
| 90 # # That blocks the thread, *and* releases the lock. When a | |
| 91 # # condition.signal() happens, it will wake up some thread that | |
| 92 # # did a .wait, *and* acquire the lock again before .wait | |
| 93 # # returns. | |
| 94 # # | |
| 95 # # Because the lock is acquired at this point, the state used | |
| 96 # # in evaluating the ACC is frozen, so it's safe to go back & | |
| 97 # # reevaluate the ACC. | |
| 98 # | |
| 99 # # At this point, ACC is true, and the thread has the condition | |
| 100 # # locked. | |
| 101 # # So code here can safely muck with the shared state that | |
| 102 # # went into evaluating the ACC -- if it wants to. | |
| 103 # # When done mucking with the shared state, do | |
| 104 # condition.release() | |
| 105 # | |
| 106 # B) Threads that are mucking with shared state that may affect the | |
| 107 # ACC do: | |
| 108 # | |
| 109 # condition.acquire() | |
| 110 # # muck with shared state | |
| 111 # condition.release() | |
| 112 # if it's possible that ACC is true now: | |
| 113 # condition.signal() # or .broadcast() | |
| 114 # | |
| 115 # Note: You may prefer to put the "if" clause before the release(). | |
| 116 # That's fine, but do note that anyone waiting on the signal will | |
| 117 # stay blocked until the release() is done (since acquiring the | |
| 118 # condition is part of what .wait() does before it returns). | |
| 119 # | |
| 120 # TRICK OF THE TRADE | |
| 121 # | |
| 122 # With simpler forms of conditions, it can be impossible to know when | |
| 123 # a thread that's supposed to do a .wait has actually done it. But | |
| 124 # because this form of condition releases a lock as _part_ of doing a | |
| 125 # wait, the state of that lock can be used to guarantee it. | |
| 126 # | |
| 127 # E.g., suppose thread A spawns thread B and later wants to wait for B to | |
| 128 # complete: | |
| 129 # | |
| 130 # In A: In B: | |
| 131 # | |
| 132 # B_done = condition() ... do work ... | |
| 133 # B_done.acquire() B_done.acquire(); B_done.release() | |
| 134 # spawn B B_done.signal() | |
| 135 # ... some time later ... ... and B exits ... | |
| 136 # B_done.wait() | |
| 137 # | |
| 138 # Because B_done was in the acquire'd state at the time B was spawned, | |
| 139 # B's attempt to acquire B_done can't succeed until A has done its | |
| 140 # B_done.wait() (which releases B_done). So B's B_done.signal() is | |
| 141 # guaranteed to be seen by the .wait(). Without the lock trick, B | |
| 142 # may signal before A .waits, and then A would wait forever. | |
| 143 # | |
| 144 # BARRIERS | |
| 145 # | |
| 146 # A barrier object is created via | |
| 147 # import this_module | |
| 148 # your_barrier = this_module.barrier(num_threads) | |
| 149 # | |
| 150 # Methods: | |
| 151 # .enter() | |
| 152 # the thread blocks until num_threads threads in all have done | |
| 153 # .enter(). Then the num_threads threads that .enter'ed resume, | |
| 154 # and the barrier resets to capture the next num_threads threads | |
| 155 # that .enter it. | |
| 156 # | |
| 157 # EVENTS | |
| 158 # | |
| 159 # An event object is created via | |
| 160 # import this_module | |
| 161 # your_event = this_module.event() | |
| 162 # | |
| 163 # An event has two states, `posted' and `cleared'. An event is | |
| 164 # created in the cleared state. | |
| 165 # | |
| 166 # Methods: | |
| 167 # | |
| 168 # .post() | |
| 169 # Put the event in the posted state, and resume all threads | |
| 170 # .wait'ing on the event (if any). | |
| 171 # | |
| 172 # .clear() | |
| 173 # Put the event in the cleared state. | |
| 174 # | |
| 175 # .is_posted() | |
| 176 # Returns 0 if the event is in the cleared state, or 1 if the event | |
| 177 # is in the posted state. | |
| 178 # | |
| 179 # .wait() | |
| 180 # If the event is in the posted state, returns immediately. | |
| 181 # If the event is in the cleared state, blocks the calling thread | |
| 182 # until the event is .post'ed by another thread. | |
| 183 # | |
| 184 # Note that an event, once posted, remains posted until explicitly | |
| 185 # cleared. Relative to conditions, this is both the strength & weakness | |
| 186 # of events. It's a strength because the .post'ing thread doesn't have to | |
| 187 # worry about whether the threads it's trying to communicate with have | |
| 188 # already done a .wait (a condition .signal is seen only by threads that | |
| 189 # do a .wait _prior_ to the .signal; a .signal does not persist). But | |
| 190 # it's a weakness because .clear'ing an event is error-prone: it's easy | |
| 191 # to mistakenly .clear an event before all the threads you intended to | |
| 192 # see the event get around to .wait'ing on it. But so long as you don't | |
| 193 # need to .clear an event, events are easy to use safely. | |
| 194 # | |
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195 # SEMAPHORES |
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196 # |
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197 # A semaphore object is created via |
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198 # import this_module |
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199 # your_semaphore = this_module.semaphore(count=1) |
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200 # |
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201 # A semaphore has an integer count associated with it. The initial value |
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202 # of the count is specified by the optional argument (which defaults to |
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203 # 1) passed to the semaphore constructor. |
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204 # |
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205 # Methods: |
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206 # |
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207 # .p() |
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208 # If the semaphore's count is greater than 0, decrements the count |
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209 # by 1 and returns. |
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210 # Else if the semaphore's count is 0, blocks the calling thread |
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211 # until a subsequent .v() increases the count. When that happens, |
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212 # the count will be decremented by 1 and the calling thread resumed. |
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213 # |
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214 # .v() |
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215 # Increments the semaphore's count by 1, and wakes up a thread (if |
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216 # any) blocked by a .p(). It's an (detected) error for a .v() to |
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217 # increase the semaphore's count to a value larger than the initial |
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218 # count. |
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219 # |
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220 # MULTIPLE-READER SINGLE-WRITER LOCKS |
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221 # |
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222 # A mrsw lock is created via |
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223 # import this_module |
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224 # your_mrsw_lock = this_module.mrsw() |
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225 # |
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226 # This kind of lock is often useful with complex shared data structures. |
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227 # The object lets any number of "readers" proceed, so long as no thread |
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228 # wishes to "write". When a (one or more) thread declares its intention |
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229 # to "write" (e.g., to update a shared structure), all current readers |
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230 # are allowed to finish, and then a writer gets exclusive access; all |
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231 # other readers & writers are blocked until the current writer completes. |
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232 # Finally, if some thread is waiting to write and another is waiting to |
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233 # read, the writer takes precedence. |
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234 # |
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235 # Methods: |
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236 # |
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237 # .read_in() |
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238 # If no thread is writing or waiting to write, returns immediately. |
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239 # Else blocks until no thread is writing or waiting to write. So |
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240 # long as some thread has completed a .read_in but not a .read_out, |
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241 # writers are blocked. |
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242 # |
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243 # .read_out() |
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244 # Use sometime after a .read_in to declare that the thread is done |
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245 # reading. When all threads complete reading, a writer can proceed. |
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246 # |
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247 # .write_in() |
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248 # If no thread is writing (has completed a .write_in, but hasn't yet |
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249 # done a .write_out) or reading (similarly), returns immediately. |
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250 # Else blocks the calling thread, and threads waiting to read, until |
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251 # the current writer completes writing or all the current readers |
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252 # complete reading; if then more than one thread is waiting to |
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253 # write, one of them is allowed to proceed, but which one is not |
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254 # specified. |
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255 # |
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256 # .write_out() |
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257 # Use sometime after a .write_in to declare that the thread is done |
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258 # writing. Then if some other thread is waiting to write, it's |
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259 # allowed to proceed. Else all threads (if any) waiting to read are |
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260 # allowed to proceed. |
| 1959 | 261 # |
| 262 # .write_to_read() | |
| 263 # Use instead of a .write_in to declare that the thread is done | |
| 264 # writing but wants to continue reading without other writers | |
| 265 # intervening. If there are other threads waiting to write, they | |
| 266 # are allowed to proceed only if the current thread calls | |
| 267 # .read_out; threads waiting to read are only allowed to proceed | |
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268 # if there are no threads waiting to write. (This is a |
| 1959 | 269 # weakness of the interface!) |
| 1637 | 270 |
| 271 import thread | |
| 272 | |
| 273 class condition: | |
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274 def __init__(self, lock=None): |
| 1637 | 275 # the lock actually used by .acquire() and .release() |
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276 if lock is None: |
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277 self.mutex = thread.allocate_lock() |
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278 else: |
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279 if hasattr(lock, 'acquire') and \ |
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280 hasattr(lock, 'release'): |
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281 self.mutex = lock |
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282 else: |
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283 raise TypeError, 'condition constructor requires ' \ |
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284 'a lock argument' |
| 1637 | 285 |
| 286 # lock used to block threads until a signal | |
| 287 self.checkout = thread.allocate_lock() | |
| 288 self.checkout.acquire() | |
| 289 | |
| 290 # internal critical-section lock, & the data it protects | |
| 291 self.idlock = thread.allocate_lock() | |
| 292 self.id = 0 | |
| 293 self.waiting = 0 # num waiters subject to current release | |
| 294 self.pending = 0 # num waiters awaiting next signal | |
| 295 self.torelease = 0 # num waiters to release | |
| 296 self.releasing = 0 # 1 iff release is in progress | |
| 297 | |
| 298 def acquire(self): | |
| 299 self.mutex.acquire() | |
| 300 | |
| 301 def release(self): | |
| 302 self.mutex.release() | |
| 303 | |
| 304 def wait(self): | |
| 305 mutex, checkout, idlock = self.mutex, self.checkout, self.idlock | |
| 306 if not mutex.locked(): | |
| 307 raise ValueError, \ | |
| 308 "condition must be .acquire'd when .wait() invoked" | |
| 309 | |
| 310 idlock.acquire() | |
| 311 myid = self.id | |
| 312 self.pending = self.pending + 1 | |
| 313 idlock.release() | |
| 314 | |
| 315 mutex.release() | |
| 316 | |
| 317 while 1: | |
| 318 checkout.acquire(); idlock.acquire() | |
| 319 if myid < self.id: | |
| 320 break | |
| 321 checkout.release(); idlock.release() | |
| 322 | |
| 323 self.waiting = self.waiting - 1 | |
| 324 self.torelease = self.torelease - 1 | |
| 325 if self.torelease: | |
| 326 checkout.release() | |
| 327 else: | |
| 328 self.releasing = 0 | |
| 329 if self.waiting == self.pending == 0: | |
| 330 self.id = 0 | |
| 331 idlock.release() | |
| 332 mutex.acquire() | |
| 333 | |
| 334 def signal(self): | |
| 335 self.broadcast(1) | |
| 336 | |
| 337 def broadcast(self, num = -1): | |
| 338 if num < -1: | |
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339 raise ValueError, '.broadcast called with num %r' % (num,) |
| 1637 | 340 if num == 0: |
| 341 return | |
| 342 self.idlock.acquire() | |
| 343 if self.pending: | |
| 344 self.waiting = self.waiting + self.pending | |
| 345 self.pending = 0 | |
| 346 self.id = self.id + 1 | |
| 347 if num == -1: | |
| 348 self.torelease = self.waiting | |
| 349 else: | |
| 350 self.torelease = min( self.waiting, | |
| 351 self.torelease + num ) | |
| 352 if self.torelease and not self.releasing: | |
| 353 self.releasing = 1 | |
| 354 self.checkout.release() | |
| 355 self.idlock.release() | |
| 356 | |
| 357 class barrier: | |
| 358 def __init__(self, n): | |
| 359 self.n = n | |
| 360 self.togo = n | |
| 361 self.full = condition() | |
| 362 | |
| 363 def enter(self): | |
| 364 full = self.full | |
| 365 full.acquire() | |
| 366 self.togo = self.togo - 1 | |
| 367 if self.togo: | |
| 368 full.wait() | |
| 369 else: | |
| 370 self.togo = self.n | |
| 371 full.broadcast() | |
| 372 full.release() | |
| 373 | |
| 374 class event: | |
| 375 def __init__(self): | |
| 376 self.state = 0 | |
| 377 self.posted = condition() | |
| 378 | |
| 379 def post(self): | |
| 380 self.posted.acquire() | |
| 381 self.state = 1 | |
| 382 self.posted.broadcast() | |
| 383 self.posted.release() | |
| 384 | |
| 385 def clear(self): | |
| 386 self.posted.acquire() | |
| 387 self.state = 0 | |
| 388 self.posted.release() | |
| 389 | |
| 390 def is_posted(self): | |
| 391 self.posted.acquire() | |
| 392 answer = self.state | |
| 393 self.posted.release() | |
| 394 return answer | |
| 395 | |
| 396 def wait(self): | |
| 397 self.posted.acquire() | |
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398 if not self.state: |
| 1637 | 399 self.posted.wait() |
| 400 self.posted.release() | |
| 401 | |
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402 class semaphore: |
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403 def __init__(self, count=1): |
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404 if count <= 0: |
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405 raise ValueError, 'semaphore count %d; must be >= 1' % count |
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406 self.count = count |
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407 self.maxcount = count |
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408 self.nonzero = condition() |
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409 |
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410 def p(self): |
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411 self.nonzero.acquire() |
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412 while self.count == 0: |
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413 self.nonzero.wait() |
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414 self.count = self.count - 1 |
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415 self.nonzero.release() |
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416 |
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417 def v(self): |
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418 self.nonzero.acquire() |
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419 if self.count == self.maxcount: |
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420 raise ValueError, '.v() tried to raise semaphore count above ' \ |
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421 'initial value %r' % self.maxcount |
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422 self.count = self.count + 1 |
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423 self.nonzero.signal() |
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424 self.nonzero.release() |
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425 |
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426 class mrsw: |
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427 def __init__(self): |
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428 # critical-section lock & the data it protects |
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429 self.rwOK = thread.allocate_lock() |
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430 self.nr = 0 # number readers actively reading (not just waiting) |
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431 self.nw = 0 # number writers either waiting to write or writing |
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432 self.writing = 0 # 1 iff some thread is writing |
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433 |
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434 # conditions |
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435 self.readOK = condition(self.rwOK) # OK to unblock readers |
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436 self.writeOK = condition(self.rwOK) # OK to unblock writers |
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437 |
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438 def read_in(self): |
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439 self.rwOK.acquire() |
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440 while self.nw: |
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441 self.readOK.wait() |
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442 self.nr = self.nr + 1 |
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443 self.rwOK.release() |
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444 |
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445 def read_out(self): |
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446 self.rwOK.acquire() |
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447 if self.nr <= 0: |
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448 raise ValueError, \ |
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449 '.read_out() invoked without an active reader' |
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450 self.nr = self.nr - 1 |
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451 if self.nr == 0: |
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452 self.writeOK.signal() |
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453 self.rwOK.release() |
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454 |
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455 def write_in(self): |
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456 self.rwOK.acquire() |
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457 self.nw = self.nw + 1 |
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458 while self.writing or self.nr: |
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459 self.writeOK.wait() |
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460 self.writing = 1 |
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461 self.rwOK.release() |
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462 |
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463 def write_out(self): |
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464 self.rwOK.acquire() |
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465 if not self.writing: |
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466 raise ValueError, \ |
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467 '.write_out() invoked without an active writer' |
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468 self.writing = 0 |
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469 self.nw = self.nw - 1 |
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470 if self.nw: |
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471 self.writeOK.signal() |
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472 else: |
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473 self.readOK.broadcast() |
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474 self.rwOK.release() |
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475 |
| 1959 | 476 def write_to_read(self): |
| 9108 | 477 self.rwOK.acquire() |
| 478 if not self.writing: | |
| 479 raise ValueError, \ | |
| 480 '.write_to_read() invoked without an active writer' | |
| 481 self.writing = 0 | |
| 482 self.nw = self.nw - 1 | |
| 483 self.nr = self.nr + 1 | |
| 484 if not self.nw: | |
| 485 self.readOK.broadcast() | |
| 486 self.rwOK.release() | |
| 1959 | 487 |
| 1637 | 488 # The rest of the file is a test case, that runs a number of parallelized |
| 489 # quicksorts in parallel. If it works, you'll get about 600 lines of | |
| 490 # tracing output, with a line like | |
| 491 # test passed! 209 threads created in all | |
| 492 # as the last line. The content and order of preceding lines will | |
| 493 # vary across runs. | |
| 494 | |
| 495 def _new_thread(func, *args): | |
| 496 global TID | |
| 497 tid.acquire(); id = TID = TID+1; tid.release() | |
| 498 io.acquire(); alive.append(id); \ | |
| 499 print 'starting thread', id, '--', len(alive), 'alive'; \ | |
| 500 io.release() | |
| 501 thread.start_new_thread( func, (id,) + args ) | |
| 502 | |
| 503 def _qsort(tid, a, l, r, finished): | |
| 504 # sort a[l:r]; post finished when done | |
| 505 io.acquire(); print 'thread', tid, 'qsort', l, r; io.release() | |
| 506 if r-l > 1: | |
| 507 pivot = a[l] | |
| 508 j = l+1 # make a[l:j] <= pivot, and a[j:r] > pivot | |
| 509 for i in range(j, r): | |
| 510 if a[i] <= pivot: | |
| 511 a[j], a[i] = a[i], a[j] | |
| 512 j = j + 1 | |
| 513 a[l], a[j-1] = a[j-1], pivot | |
| 514 | |
| 515 l_subarray_sorted = event() | |
| 516 r_subarray_sorted = event() | |
| 517 _new_thread(_qsort, a, l, j-1, l_subarray_sorted) | |
| 518 _new_thread(_qsort, a, j, r, r_subarray_sorted) | |
| 519 l_subarray_sorted.wait() | |
| 520 r_subarray_sorted.wait() | |
| 521 | |
| 522 io.acquire(); print 'thread', tid, 'qsort done'; \ | |
| 523 alive.remove(tid); io.release() | |
| 524 finished.post() | |
| 525 | |
| 526 def _randarray(tid, a, finished): | |
| 527 io.acquire(); print 'thread', tid, 'randomizing array'; \ | |
| 528 io.release() | |
| 529 for i in range(1, len(a)): | |
| 530 wh.acquire(); j = randint(0,i); wh.release() | |
| 531 a[i], a[j] = a[j], a[i] | |
| 532 io.acquire(); print 'thread', tid, 'randomizing done'; \ | |
| 533 alive.remove(tid); io.release() | |
| 534 finished.post() | |
| 535 | |
| 536 def _check_sort(a): | |
| 537 if a != range(len(a)): | |
| 538 raise ValueError, ('a not sorted', a) | |
| 539 | |
| 540 def _run_one_sort(tid, a, bar, done): | |
| 541 # randomize a, and quicksort it | |
| 542 # for variety, all the threads running this enter a barrier | |
| 543 # at the end, and post `done' after the barrier exits | |
| 544 io.acquire(); print 'thread', tid, 'randomizing', a; \ | |
| 545 io.release() | |
| 546 finished = event() | |
| 547 _new_thread(_randarray, a, finished) | |
| 548 finished.wait() | |
| 549 | |
| 550 io.acquire(); print 'thread', tid, 'sorting', a; io.release() | |
| 551 finished.clear() | |
| 552 _new_thread(_qsort, a, 0, len(a), finished) | |
| 553 finished.wait() | |
| 554 _check_sort(a) | |
| 555 | |
| 556 io.acquire(); print 'thread', tid, 'entering barrier'; \ | |
| 557 io.release() | |
| 558 bar.enter() | |
| 559 io.acquire(); print 'thread', tid, 'leaving barrier'; \ | |
| 560 io.release() | |
| 561 io.acquire(); alive.remove(tid); io.release() | |
| 562 bar.enter() # make sure they've all removed themselves from alive | |
| 563 ## before 'done' is posted | |
| 564 bar.enter() # just to be cruel | |
| 565 done.post() | |
| 566 | |
| 567 def test(): | |
| 568 global TID, tid, io, wh, randint, alive | |
| 8395 | 569 import random |
| 570 randint = random.randint | |
| 1637 | 571 |
| 572 TID = 0 # thread ID (1, 2, ...) | |
| 573 tid = thread.allocate_lock() # for changing TID | |
| 574 io = thread.allocate_lock() # for printing, and 'alive' | |
| 8395 | 575 wh = thread.allocate_lock() # for calls to random |
| 1637 | 576 alive = [] # IDs of active threads |
| 577 | |
| 578 NSORTS = 5 | |
| 579 arrays = [] | |
| 580 for i in range(NSORTS): | |
| 581 arrays.append( range( (i+1)*10 ) ) | |
| 582 | |
| 583 bar = barrier(NSORTS) | |
| 584 finished = event() | |
| 585 for i in range(NSORTS): | |
| 586 _new_thread(_run_one_sort, arrays[i], bar, finished) | |
| 587 finished.wait() | |
| 588 | |
| 589 print 'all threads done, and checking results ...' | |
| 590 if alive: | |
| 591 raise ValueError, ('threads still alive at end', alive) | |
| 592 for i in range(NSORTS): | |
| 593 a = arrays[i] | |
| 594 if len(a) != (i+1)*10: | |
| 595 raise ValueError, ('length of array', i, 'screwed up') | |
| 596 _check_sort(a) | |
| 597 | |
| 598 print 'test passed!', TID, 'threads created in all' | |
| 599 | |
| 600 if __name__ == '__main__': | |
| 601 test() | |
| 602 | |
| 603 # end of module |