1#!/usr/bin/env python 2# Copyright 2010 Google Inc. All Rights Reserved. 3# 4# Licensed under the Apache License, Version 2.0 (the "License"); 5# you may not use this file except in compliance with the License. 6# You may obtain a copy of the License at 7# 8# http://www.apache.org/licenses/LICENSE-2.0 9# 10# Unless required by applicable law or agreed to in writing, software 11# distributed under the License is distributed on an "AS IS" BASIS, 12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13# See the License for the specific language governing permissions and 14# limitations under the License. 15 16import threading 17 18 19class DaemonServer(object): 20 """Base class which manages creation and cleanup of daemon style servers.""" 21 22 def __enter__(self): 23 # TODO: Because of python's Global Interpreter Lock (GIL), the threads 24 # will run on the same CPU. Consider using processes instead because 25 # the components do not need to communicate with each other. On Linux, 26 # "taskset" could be used to assign each process to specific CPU/core. 27 # Of course, only bother with this if the processing speed is an issue. 28 # Some related discussion: http://stackoverflow.com/questions/990102/python- 29 # global-interpreter-lock-gil-workaround-on-multi-core-systems-using-tasks 30 thread = threading.Thread(target=self.serve_forever) 31 thread.daemon = True # Python exits when no non-daemon threads are left. 32 thread.start() 33 return self 34 35 def __exit__(self, unused_exc_type, unused_exc_val, unused_exc_tb): 36 self.cleanup() 37