Python Condition.acquire方法代码示例

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
    def __call__(self, cv_iterator, evaluator, fold_callback=None,
                 n_jobs=None):
        """
        """
        condvar = Condition()
        results = []

        def _signal_cb(result):
            condvar.acquire()
            results.append(result)
            condvar.notify()
            condvar.release()
        folds = list(cv_iterator)

        pool, deferreds = self.async(folds, evaluator,
                                     fold_callback=_signal_cb, n_jobs=n_jobs)
        pool.close()
        while len(results) < len(folds):
            condvar.acquire()
            condvar.wait()
            fold_estimator, result = results[-1]
            fold_callback(fold_estimator, result)
            condvar.release()
        pool.join()
        return results

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
def test_watch_directory():

    def _cleanup(path):
        for f in listdir(path):
            p = join(path, f)
            if isdir(p):
                rmtree(p)
            elif f != '.nothing':
                unlink(p)

    sample_template = ''
    sample_directory = dirname(realpath(__file__)) + '/sample/'
    watch_directory = sample_directory + 'watch/'
    render_directory = sample_directory + 'render/'
    template_directory = sample_directory + 'templates/'
    with open(template_directory + 'haml.tmpl', 'r') as f:
        sample_template = f.read()

    condition = Condition()
    p = Process(target=reloader.watch_directory,
                args=(watch_directory, render_directory, condition))
    condition.acquire()
    p.start()
    condition.wait()

    try:
        with open(watch_directory + 'test.haml', 'w') as f:
            f.write(sample_template)

        subdir = watch_directory + 'test_subdir/'
        try:
            mkdir(subdir)
        except OSError:
            if not isdir(subdir):
                raise
        with open(subdir + 'test_two.haml', 'w') as f:
            f.write(sample_template)

        sleep(1)

        assert_true(exists(render_directory + 'test.html'))
        assert_true(exists(render_directory + 'test_subdir/test_two.html'))
    except:
        raise
    finally:
        condition.release()
        p.terminate()
        p.join()

        sleep(1)

        _cleanup(watch_directory)
        _cleanup(render_directory)

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
class SynchronizingBus(Bus):
    def __init__(self, sync_delay=1):
        Bus.__init__(self)
        self.sync_delay = sync_delay
        self.condition = Condition()

    def start(self):
        import time
        time.sleep(self.sync_delay)
        self.log("Releasing children")
        self.condition.acquire()
        self.condition.notify_all()
        self.condition.release()
        Bus.start(self)

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
class TProcessPoolServer(TServer):

    """
    Server with a fixed size pool of worker subprocesses which service requests.
    Note that if you need shared state between the handlers - it's up to you!
    Written by Dvir Volk, doat.com
    """

    def __init__(self, * args):
        TServer.__init__(self, *args)
        self.numWorkers = 10
        self.workers = []
        self.isRunning = Value('b', False)
        self.stopCondition = Condition()
        self.postForkCallback = None

    def setPostForkCallback(self, callback):
        if not callable(callback):
            raise TypeError("This is not a callback!")
        self.postForkCallback = callback

    def setNumWorkers(self, num):
        """Set the number of worker threads that should be created"""
        self.numWorkers = num

    def workerProcess(self):
        """Loop around getting clients from the shared queue and process them."""

        if self.postForkCallback:
            self.postForkCallback()

        while self.isRunning.value == True:
            try:
                client = self.serverTransport.accept()
                self.serveClient(client)
            except (KeyboardInterrupt, SystemExit):
                return 0
            except (Exception) as x:
                logging.exception(x)

    def serveClient(self, client):
        """Process input/output from a client for as long as possible"""
        itrans = self.inputTransportFactory.getTransport(client)
        otrans = self.outputTransportFactory.getTransport(client)
        iprot = self.inputProtocolFactory.getProtocol(itrans)
        oprot = self.outputProtocolFactory.getProtocol(otrans)

        try:
            while True:
                self.processor.process(iprot, oprot)
        except (TTransportException) as tx:
            pass
        except (Exception) as x:
            logging.exception(x)

        itrans.close()
        otrans.close()


    def serve(self):
        """Start a fixed number of worker threads and put client into a queue"""

        #this is a shared state that can tell the workers to exit when set as false
        self.isRunning.value = True

        #first bind and listen to the port
        self.serverTransport.listen()

        #fork the children
        for i in range(self.numWorkers):
            try:
                w = Process(target=self.workerProcess)
                w.daemon = True
                w.start()
                self.workers.append(w)
            except (Exception) as x:
                logging.exception(x)

        #wait until the condition is set by stop()

        while True:

            self.stopCondition.acquire()
            try:
                self.stopCondition.wait()
                break
            except (SystemExit, KeyboardInterrupt):
		break
            except (Exception) as x:
                logging.exception(x)

        self.isRunning.value = False

    def stop(self):
        self.isRunning.value = False
        self.stopCondition.acquire()
        self.stopCondition.notify()
        self.stopCondition.release()

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
import time

from multiprocessing import Process, Condition
import os

cond = Condition()

def wait_condition():
    cond.acquire()
    cond.wait()
    print '[%d] waked!' % os.getpid()
    cond.release()

for i in range(3):
    Process(target=wait_condition).start()

time.sleep(1)
print 'notify!'
cond.acquire()
cond.notify_all()
cond.release()

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
class WaitableQueue(Queue):
    """Queue that uses a semaphore to reliably count items in it"""
    class Vacuum(ThreadLoop):
        def __init__(self, q, l):
            def callback():
                q.wait_notempty(0.1)

                while True:
                    try:
                        val = q.get(False)
                        l.append(val)

                    except Empty:
                        break

            ThreadLoop.__init__(self, callback)

    def __init__(self, maxsize=0):
        self.cond_empty = Condition()
        self.cond_notempty = Condition()
        self._put_counter = Value('i', 0)

        Queue.__init__(self, maxsize)

    def put(self, obj, block=True, timeout=None):
        Queue.put(self, obj, block, timeout)
        self._put_counter.value += 1

        if self.qsize() != 0:
            self.cond_notempty.acquire()
            try:
                self.cond_notempty.notify_all()
            finally:
                self.cond_notempty.release()

    @property
    def put_counter(self):
        return self._put_counter.value

    def get(self, block=True, timeout=None):
        ret = Queue.get(self, block, timeout)
        if self.qsize() == 0:
            self.cond_empty.acquire()
            try:
                self.cond_empty.notify_all()
            finally:
                self.cond_empty.release()

        return ret

    def wait_empty(self, timeout=None):
        """Wait for all items to be got"""
        self.cond_empty.acquire()
        try:
            if self.qsize():
                self.cond_empty.wait(timeout)
        finally:
            self.cond_empty.release()

    def wait_notempty(self, timeout=None):
        """Wait for all items to be got"""
        self.cond_notempty.acquire()
        try:
            if self.qsize() == 0:
                self.cond_notempty.wait(timeout)
        finally:
            self.cond_notempty.release()

# 需要导入模块: from multiprocessing import Condition [as 别名]
# 或者: from multiprocessing.Condition import acquire [as 别名]
class RWLock():
    """A Readers-Writer lock.
    
    Allows for multiple readers or one writer. Writers will not starve.

    Attributes:
        for_reading (RWLock.ReadLock): A lock-like object with appropriate
            `acquire`, `release`, `__enter__` and `__exit__` methods pointed
            to the *read methods of the RWLock. Chiefly for use with the 
            `with` statement.
        for_writing (RWLock.WriteLock): A lock-like object with appropriate
            `acquire`, `release`, `__enter__` and `__exit__` methods pointed
            to the *write methods of the RWLock. Chiefly for use with the 
            `with` statement.

    """
    class ReadLock():
        def __init__(self, rw):
            self._rw = rw
            self.acquire = rw.acquire_read
            self.release = rw.release_read
        def __enter__(self):
            self.acquire()
        def __exit__(self, exception_type, exception_value, traceback):
            self.release()

    class WriteLock():
        def __init__(self, rw):
            self._rw = rw
            self.acquire = rw.acquire_write
            self.release = rw.release_write
        def __enter__(self):
            self.acquire()
        def __exit__(self, exception_type, exception_value, traceback):
            self.release()

    def __init__(self):
        """Initialises the RWLock."""
        self._condition = Condition()
        self._readers = Value(c_uint64, 0, lock=False)
        self._writers_waiting = Value(c_uint64, 0, lock=False)

        self.for_reading = self.ReadLock(self)
        self.for_writing = self.WriteLock(self)

    def acquire_read(self):
        """Acquire a read lock. 
        
        Blocks if a thread has acquired the write lock or is waiting to
        acquire the write lock.
        
        """
        with self._condition:
            while self._writers_waiting.value:
                self._condition.wait()
            self._readers.value += 1

    def release_read(self):
        """Release a read lock."""
        with self._condition:
            self._readers.value -= 1
            if not self._readers.value:
                self._condition.notify_all()

    def acquire_write(self):
        """Acquire a write lock.
        
        Blocks until there are no acquired read or write locks.
        
        """
        self._condition.acquire()
        self._writers_waiting.value += 1
        while self._readers.value:
            self._condition.wait()
        self._writers_waiting.value -= 1

    def release_write(self):
        """Release a write lock."""
        self._condition.release()