Add WORKER_POOL environmental option to facilitate pysawsim.manager benchmarking.

[sawsim.git] / pysawsim / manager / subproc.py

diff --git a/pysawsim/manager/subproc.py b/pysawsim/manager/subproc.py
index ad0d64bc693595754e2313555ec7078615a06b1c..6a17078ab4cb2a9978eec68b7116da7ca99441a2 100644 (file)
--- a/pysawsim/manager/subproc.py
+++ b/pysawsim/manager/subproc.py
@@ -22,19 +22,50 @@
 
 try:
     from multiprocessing import Manager, Process, Queue, cpu_count
+    _ENABLED = True
+    _DISABLING_ERROR = None
     _SKIP = ''
-except ImportError, multiprocessing_error:
+except ImportError, _DISABLING_ERROR:
+    _ENABLED = False
     Process = object
     _SKIP = '  # doctest: +SKIP'
 
+import os
+
 from .. import log
 from . import Job
 from .thread import ThreadManager, CLOSE_MESSAGE
 
+
+if _ENABLED == True:
+    """Check succeptibility to python issue 5313:
+      http://bugs.python.org/issue5155
+      http://bugs.python.org/issue5313
+      http://svn.python.org/view?view=rev&revision=73708
+
+    Fix merged into the 2.6 maintenance branch with
+
+      changeset:   531:11e5b7504a71
+      branch:      release26-maint
+      user:        r.david.murray
+      date:        Tue Jul 21 19:02:14 2009 +0200
+      summary:     [svn r74145] Merged revisions 73708,73738 via svnmerge...
+
+    Which came between 2.6.2 and 2.6.3rc1
+
+      $ hg blame -r 631 README | grep 'version 2\.6\.'
+      631: This is Python version 2.6.3rc1
+      $ hg blame -r 630 README | grep 'version 2\.6\.'
+      345: This is Python version 2.6.2
+    """
+    import sys
+    _HAS_BUG_5313 = sys.version_info < (2,6,3)
+
+
 class WorkerProcess (Process):
     def __init__(self, spawn_queue, receive_queue, *args, **kwargs):
-        if Process == object:
-            raise multiprocessing_error
+        if _ENABLED == False:
+            raise _DISABLING_ERROR
         super(WorkerProcess, self).__init__(*args, **kwargs)
         self.spawn_queue = spawn_queue
         self.receive_queue = receive_queue
@@ -77,8 +108,8 @@ class SubprocessManager (ThreadManager):
     >>> m.teardown()%(skip)s
     """ % {'skip': _SKIP}
     def __init__(self, worker_pool=None):
-        if Process == object:
-            raise multiprocessing_error
+        if _ENABLED == False:
+            raise _DISABLING_ERROR
         super(SubprocessManager, self).__init__(worker_pool=worker_pool)
 
     def _setup_queues(self):
@@ -86,8 +117,8 @@ class SubprocessManager (ThreadManager):
         self._receive_queue = Queue()
 
     def _spawn_workers(self, worker_pool=None):
-        if worker_pool == None:
-            worker_pool = cpu_count() + 1
+        if worker_pool is None:
+            worker_pool = int(os.environ.get('WORKER_POOL', cpu_count() + 1))
         self._manager = Manager()
         self._workers = []
         for i in range(worker_pool):