PyQt：带有 QRunnables 的 QThreadPool 需要时间退出
PyQt: QThreadPool with QRunnables taking time to quit
我有一个 class 创建 QRunnables 并在 QThreadPool 实例中启动它们。
我的线程运行良好，但万一用户想退出应用程序，应用程序需要很长时间才能停止。当然是因为发起请求需要时间。
这是我如何使用 QThreadPool、QRunnables 的代码片段：
import sys
from PyQt5.Qt import QThreadPool, QApplication, QWidget, QVBoxLayout
from PyQt5.Qt import QTimer, QObject, QPushButton, QLabel
from PyQt5.Qt import QRunnable
class BackendQRunnable(QRunnable):
"""
Class who create a QThread to trigger requests
"""
def __init__(self, task):
super(BackendQRunnable, self).__init__()
self.task = task
def run(self):
"""
Run the QRunnable. Trigger actions depending on the selected task
"""
# Here I make long requests
if 'user' in self.task:
self.query_user_data()
elif 'host' in self.task:
self.query_hosts_data()
elif 'service' in self.task:
self.query_services_data()
elif 'alignakdaemon' in self.task:
self.query_daemons_data()
elif 'livesynthesis' in self.task:
self.query_livesynthesis_data()
elif 'history' in self.task:
self.query_history_data()
elif 'notifications' in self.task:
self.query_notifications_data()
else:
pass
@staticmethod
def query_user_data():
"""
Launch request for "user" endpoint
"""
print('Query user data')
@staticmethod
def query_hosts_data():
"""
Launch request for "host" endpoint
"""
print('Query hosts')
@staticmethod
def query_services_data():
"""
Launch request for "service" endpoint
"""
print("Query services")
@staticmethod
def query_daemons_data():
"""
Launch request for "alignakdaemon" endpoint
"""
print('Query daemons')
@staticmethod
def query_livesynthesis_data():
"""
Launch request for "livesynthesis" endpoint
"""
print('query livesynthesis')
@staticmethod
def query_history_data():
"""
Launch request for "history" endpoint but only for hosts in "data_manager"
"""
print('Query history')
@staticmethod
def query_notifications_data():
"""
Launch request for "history" endpoint but only for notifications of current user
"""
print('Query notifications')
class ThreadManager(QObject):
"""
Class who create BackendQRunnable to periodically request on a Backend
"""
def __init__(self, parent=None):
super(ThreadManager, self).__init__(parent)
self.backend_thread = BackendQRunnable(self)
self.pool = QThreadPool.globalInstance()
self.tasks = self.get_tasks()
def start(self):
"""
Start ThreadManager
"""
print("Start backend Manager...")
# Make a first request
self.create_tasks()
# Then request periodically
timer = QTimer(self)
timer.setInterval(10000)
timer.start()
timer.timeout.connect(self.create_tasks)
@staticmethod
def get_tasks():
"""
Return the tasks to run in BackendQRunnable
:return: tasks to run
:rtype: list
"""
return [
'notifications', 'livesynthesis', 'alignakdaemon', 'history', 'service', 'host', 'user',
]
def create_tasks(self):
"""
Create tasks to run
"""
for cur_task in self.tasks:
backend_thread = BackendQRunnable(cur_task)
# Add task to QThreadPool
self.pool.start(backend_thread)
def exit_pool(self):
"""
Exit all BackendQRunnables and delete QThreadPool
"""
# When trying to quit, the application takes a long time to stop
self.pool.globalInstance().waitForDone()
self.pool.deleteLater()
sys.exit(0)
if __name__ == '__main__':
app = QApplication(sys.argv)
thread_manager = ThreadManager()
thread_manager.start()
layout = QVBoxLayout()
label = QLabel("Start")
button = QPushButton("DANGER!")
button.pressed.connect(thread_manager.exit_pool)
layout.addWidget(label)
layout.addWidget(button)
w = QWidget()
w.setLayout(layout)
w.show()
sys.exit(app.exec_())
在函数 exit_pool 中，我等到线程完成并删除 QThreadPool 实例...
有没有办法不等待每个线程直接停止一切？
编辑解决方案：
所以我以不同的方式处理了这个主题。我用 QThread 替换了我的 QRunnable。我删除了 QThreadPool 并在列表中自己管理线程。我还添加了一个 pyqtSignal 以停止 QTimer 并通过 quit() 函数关闭 运行 线程。
就这样我所有的线程都顺利退出了。
import sys
from PyQt5.Qt import QThread, QApplication, QWidget, QVBoxLayout
from PyQt5.Qt import QTimer, QObject, QPushButton, QLabel, pyqtSignal
class BackendQThread(QThread):
"""
Class who create a QThread to trigger requests
"""
quit_thread = pyqtSignal(name='close_thread')
def __init__(self, task):
super(BackendQThread, self).__init__()
self.task = task
def run(self):
"""
Run the actions depending on the selected task
"""
# Here I make long requests
if 'user' in self.task:
self.query_user_data()
elif 'host' in self.task:
self.query_hosts_data()
elif 'service' in self.task:
self.query_services_data()
elif 'alignakdaemon' in self.task:
self.query_daemons_data()
elif 'livesynthesis' in self.task:
self.query_livesynthesis_data()
elif 'history' in self.task:
self.query_history_data()
elif 'notifications' in self.task:
self.query_notifications_data()
else:
pass
@staticmethod
def query_user_data():
"""
Launch request for "user" endpoint
"""
print('Query user data')
@staticmethod
def query_hosts_data():
"""
Launch request for "host" endpoint
"""
print('Query hosts')
@staticmethod
def query_services_data():
"""
Launch request for "service" endpoint
"""
print("Query services")
@staticmethod
def query_daemons_data():
"""
Launch request for "alignakdaemon" endpoint
"""
print('Query daemons')
@staticmethod
def query_livesynthesis_data():
"""
Launch request for "livesynthesis" endpoint
"""
print('query livesynthesis')
@staticmethod
def query_history_data():
"""
Launch request for "history" endpoint but only for hosts in "data_manager"
"""
print('Query history')
@staticmethod
def query_notifications_data():
"""
Launch request for "history" endpoint but only for notifications of current user
"""
print('Query notifications')
class ThreadManager(QObject):
"""
Class who create BackendQThread to periodically request on a Backend
"""
def __init__(self, parent=None):
super(ThreadManager, self).__init__(parent)
self.tasks = self.get_tasks()
self.timer = QTimer()
self.threads = []
def start(self):
"""
Start ThreadManager
"""
print("Start backend Manager...")
# Make a first request
self.create_tasks()
# Then request periodically
self.timer.setInterval(10000)
self.timer.start()
self.timer.timeout.connect(self.create_tasks)
@staticmethod
def get_tasks():
"""
Return the available tasks to run
:return: tasks to run
:rtype: list
"""
return [
'notifications', 'livesynthesis', 'alignakdaemon', 'history', 'service', 'host', 'user',
]
def create_tasks(self):
"""
Create tasks to run
"""
# Here I reset the list of threads
self.threads = []
for cur_task in self.tasks:
backend_thread = BackendQThread(cur_task)
# Add task to QThreadPool
backend_thread.start()
self.threads.append(backend_thread)
def stop(self):
"""
Stop the manager and close all QThreads
"""
print("Stop tasks")
self.timer.stop()
for task in self.threads:
task.quit_thread.emit()
print("Tasks finished")
if __name__ == '__main__':
app = QApplication(sys.argv)
layout = QVBoxLayout()
widget = QWidget()
widget.setLayout(layout)
thread_manager = ThreadManager()
start_btn = QPushButton("Start")
start_btn.clicked.connect(thread_manager.start)
layout.addWidget(start_btn)
stop_btn = QPushButton("Stop")
stop_btn.clicked.connect(thread_manager.stop)
layout.addWidget(stop_btn)
widget.show()
sys.exit(app.exec_())
QRunnable 一旦启动就无法停止。但是，您可以通过一些简单的操作来减少示例中的等待时间。
首先，您可以停止计时器，使其不再添加任何任务。其次，你可以clear the thread-pool so that it removes any pending tasks. Thirdly, you could try setting a smaller maximum thread count看看它是否仍然达到了可接受的性能。默认情况下，线程池将使用 QThread.idealThreadCount() 来设置最大线程数——这通常意味着系统上的每个处理器核心一个。
最后一个选项是提供一种方法来中断在您的可运行程序中执行的代码。只有当代码运行一个循环可以定期检查标志以查看它是否应该继续时，这才真正成为可能。在您的示例中，看起来您可以为标志使用单个共享 class 属性，因为所有任务都调用静态方法。但是，如果代码以这种方式不可中断，则您无能为力 - 您只需等待当前 运行 任务完成即可。
我有一个 class 创建 QRunnables 并在 QThreadPool 实例中启动它们。
我的线程运行良好，但万一用户想退出应用程序，应用程序需要很长时间才能停止。当然是因为发起请求需要时间。
这是我如何使用 QThreadPool、QRunnables 的代码片段：
import sys
from PyQt5.Qt import QThreadPool, QApplication, QWidget, QVBoxLayout
from PyQt5.Qt import QTimer, QObject, QPushButton, QLabel
from PyQt5.Qt import QRunnable
class BackendQRunnable(QRunnable):
"""
Class who create a QThread to trigger requests
"""
def __init__(self, task):
super(BackendQRunnable, self).__init__()
self.task = task
def run(self):
"""
Run the QRunnable. Trigger actions depending on the selected task
"""
# Here I make long requests
if 'user' in self.task:
self.query_user_data()
elif 'host' in self.task:
self.query_hosts_data()
elif 'service' in self.task:
self.query_services_data()
elif 'alignakdaemon' in self.task:
self.query_daemons_data()
elif 'livesynthesis' in self.task:
self.query_livesynthesis_data()
elif 'history' in self.task:
self.query_history_data()
elif 'notifications' in self.task:
self.query_notifications_data()
else:
pass
@staticmethod
def query_user_data():
"""
Launch request for "user" endpoint
"""
print('Query user data')
@staticmethod
def query_hosts_data():
"""
Launch request for "host" endpoint
"""
print('Query hosts')
@staticmethod
def query_services_data():
"""
Launch request for "service" endpoint
"""
print("Query services")
@staticmethod
def query_daemons_data():
"""
Launch request for "alignakdaemon" endpoint
"""
print('Query daemons')
@staticmethod
def query_livesynthesis_data():
"""
Launch request for "livesynthesis" endpoint
"""
print('query livesynthesis')
@staticmethod
def query_history_data():
"""
Launch request for "history" endpoint but only for hosts in "data_manager"
"""
print('Query history')
@staticmethod
def query_notifications_data():
"""
Launch request for "history" endpoint but only for notifications of current user
"""
print('Query notifications')
class ThreadManager(QObject):
"""
Class who create BackendQRunnable to periodically request on a Backend
"""
def __init__(self, parent=None):
super(ThreadManager, self).__init__(parent)
self.backend_thread = BackendQRunnable(self)
self.pool = QThreadPool.globalInstance()
self.tasks = self.get_tasks()
def start(self):
"""
Start ThreadManager
"""
print("Start backend Manager...")
# Make a first request
self.create_tasks()
# Then request periodically
timer = QTimer(self)
timer.setInterval(10000)
timer.start()
timer.timeout.connect(self.create_tasks)
@staticmethod
def get_tasks():
"""
Return the tasks to run in BackendQRunnable
:return: tasks to run
:rtype: list
"""
return [
'notifications', 'livesynthesis', 'alignakdaemon', 'history', 'service', 'host', 'user',
]
def create_tasks(self):
"""
Create tasks to run
"""
for cur_task in self.tasks:
backend_thread = BackendQRunnable(cur_task)
# Add task to QThreadPool
self.pool.start(backend_thread)
def exit_pool(self):
"""
Exit all BackendQRunnables and delete QThreadPool
"""
# When trying to quit, the application takes a long time to stop
self.pool.globalInstance().waitForDone()
self.pool.deleteLater()
sys.exit(0)
if __name__ == '__main__':
app = QApplication(sys.argv)
thread_manager = ThreadManager()
thread_manager.start()
layout = QVBoxLayout()
label = QLabel("Start")
button = QPushButton("DANGER!")
button.pressed.connect(thread_manager.exit_pool)
layout.addWidget(label)
layout.addWidget(button)
w = QWidget()
w.setLayout(layout)
w.show()
sys.exit(app.exec_())
在函数 exit_pool 中，我等到线程完成并删除 QThreadPool 实例...
有没有办法不等待每个线程直接停止一切？
编辑解决方案：
所以我以不同的方式处理了这个主题。我用 QThread 替换了我的 QRunnable。我删除了 QThreadPool 并在列表中自己管理线程。我还添加了一个 pyqtSignal 以停止 QTimer 并通过 quit() 函数关闭 运行 线程。
就这样我所有的线程都顺利退出了。
import sys
from PyQt5.Qt import QThread, QApplication, QWidget, QVBoxLayout
from PyQt5.Qt import QTimer, QObject, QPushButton, QLabel, pyqtSignal
class BackendQThread(QThread):
"""
Class who create a QThread to trigger requests
"""
quit_thread = pyqtSignal(name='close_thread')
def __init__(self, task):
super(BackendQThread, self).__init__()
self.task = task
def run(self):
"""
Run the actions depending on the selected task
"""
# Here I make long requests
if 'user' in self.task:
self.query_user_data()
elif 'host' in self.task:
self.query_hosts_data()
elif 'service' in self.task:
self.query_services_data()
elif 'alignakdaemon' in self.task:
self.query_daemons_data()
elif 'livesynthesis' in self.task:
self.query_livesynthesis_data()
elif 'history' in self.task:
self.query_history_data()
elif 'notifications' in self.task:
self.query_notifications_data()
else:
pass
@staticmethod
def query_user_data():
"""
Launch request for "user" endpoint
"""
print('Query user data')
@staticmethod
def query_hosts_data():
"""
Launch request for "host" endpoint
"""
print('Query hosts')
@staticmethod
def query_services_data():
"""
Launch request for "service" endpoint
"""
print("Query services")
@staticmethod
def query_daemons_data():
"""
Launch request for "alignakdaemon" endpoint
"""
print('Query daemons')
@staticmethod
def query_livesynthesis_data():
"""
Launch request for "livesynthesis" endpoint
"""
print('query livesynthesis')
@staticmethod
def query_history_data():
"""
Launch request for "history" endpoint but only for hosts in "data_manager"
"""
print('Query history')
@staticmethod
def query_notifications_data():
"""
Launch request for "history" endpoint but only for notifications of current user
"""
print('Query notifications')
class ThreadManager(QObject):
"""
Class who create BackendQThread to periodically request on a Backend
"""
def __init__(self, parent=None):
super(ThreadManager, self).__init__(parent)
self.tasks = self.get_tasks()
self.timer = QTimer()
self.threads = []
def start(self):
"""
Start ThreadManager
"""
print("Start backend Manager...")
# Make a first request
self.create_tasks()
# Then request periodically
self.timer.setInterval(10000)
self.timer.start()
self.timer.timeout.connect(self.create_tasks)
@staticmethod
def get_tasks():
"""
Return the available tasks to run
:return: tasks to run
:rtype: list
"""
return [
'notifications', 'livesynthesis', 'alignakdaemon', 'history', 'service', 'host', 'user',
]
def create_tasks(self):
"""
Create tasks to run
"""
# Here I reset the list of threads
self.threads = []
for cur_task in self.tasks:
backend_thread = BackendQThread(cur_task)
# Add task to QThreadPool
backend_thread.start()
self.threads.append(backend_thread)
def stop(self):
"""
Stop the manager and close all QThreads
"""
print("Stop tasks")
self.timer.stop()
for task in self.threads:
task.quit_thread.emit()
print("Tasks finished")
if __name__ == '__main__':
app = QApplication(sys.argv)
layout = QVBoxLayout()
widget = QWidget()
widget.setLayout(layout)
thread_manager = ThreadManager()
start_btn = QPushButton("Start")
start_btn.clicked.connect(thread_manager.start)
layout.addWidget(start_btn)
stop_btn = QPushButton("Stop")
stop_btn.clicked.connect(thread_manager.stop)
layout.addWidget(stop_btn)
widget.show()
sys.exit(app.exec_())
QRunnable 一旦启动就无法停止。但是，您可以通过一些简单的操作来减少示例中的等待时间。
首先，您可以停止计时器，使其不再添加任何任务。其次，你可以clear the thread-pool so that it removes any pending tasks. Thirdly, you could try setting a smaller maximum thread count看看它是否仍然达到了可接受的性能。默认情况下，线程池将使用 QThread.idealThreadCount() 来设置最大线程数——这通常意味着系统上的每个处理器核心一个。
最后一个选项是提供一种方法来中断在您的可运行程序中执行的代码。只有当代码运行一个循环可以定期检查标志以查看它是否应该继续时，这才真正成为可能。在您的示例中，看起来您可以为标志使用单个共享 class 属性，因为所有任务都调用静态方法。但是，如果代码以这种方式不可中断，则您无能为力 - 您只需等待当前 运行 任务完成即可。