AMBARI-20070. Agent heartbeat lost due to subprocess.Popen race condition -- addendum for multiprocessing
Project: http://git-wip-us.apache.org/repos/asf/ambari/repo Commit: http://git-wip-us.apache.org/repos/asf/ambari/commit/19c9e255 Tree: http://git-wip-us.apache.org/repos/asf/ambari/tree/19c9e255 Diff: http://git-wip-us.apache.org/repos/asf/ambari/diff/19c9e255 Branch: refs/heads/branch-feature-AMBARI-12556 Commit: 19c9e25587316bceb46c1585fce712fdf5056e39 Parents: 9446252 Author: Attila Doroszlai <adorosz...@hortonworks.com> Authored: Sat Mar 11 19:13:16 2017 +0100 Committer: Attila Doroszlai <adorosz...@hortonworks.com> Committed: Mon Mar 13 22:21:59 2017 +0100 ---------------------------------------------------------------------- .../src/main/python/ambari_agent/main.py | 21 ++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/ambari/blob/19c9e255/ambari-agent/src/main/python/ambari_agent/main.py ---------------------------------------------------------------------- diff --git a/ambari-agent/src/main/python/ambari_agent/main.py b/ambari-agent/src/main/python/ambari_agent/main.py index ddef473..8e55916 100644 --- a/ambari-agent/src/main/python/ambari_agent/main.py +++ b/ambari-agent/src/main/python/ambari_agent/main.py @@ -45,23 +45,32 @@ def fix_subprocess_racecondition(): def fix_subprocess_popen(): ''' - http://bugs.python.org/issue19809 + Workaround for race condition in starting subprocesses concurrently from + multiple threads via the subprocess and multiprocessing modules. + See http://bugs.python.org/issue19809 for details and repro script. ''' import os import sys if os.name == 'posix' and sys.version_info[0] < 3: + from multiprocessing import forking import subprocess import threading - original_init = subprocess.Popen.__init__ - lock = threading.RLock() + sp_original_init = subprocess.Popen.__init__ + mp_original_init = forking.Popen.__init__ + lock = threading.RLock() # guards subprocess creation - def locked_init(self, *a, **kw): + def sp_locked_init(self, *a, **kw): with lock: - original_init(self, *a, **kw) + sp_original_init(self, *a, **kw) - subprocess.Popen.__init__ = locked_init + def mp_locked_init(self, *a, **kw): + with lock: + mp_original_init(self, *a, **kw) + + subprocess.Popen.__init__ = sp_locked_init + forking.Popen.__init__ = mp_locked_init fix_subprocess_popen()
