Add run selector + unit handling + multiprocessing + examples

mypool.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import multiprocessing
+
+# We must import this explicitly, it is not imported by the top-level
+# multiprocessing module.
+import multiprocessing.pool
+import time
+
+from random import randint
+
+
+class NoDaemonProcess(multiprocessing.Process):
+    # make 'daemon' attribute always return False
+    def _get_daemon(self):
+        return False
+
+    def _set_daemon(self, value):
+        pass
+
+    daemon = property(_get_daemon, _set_daemon)
+
+
+# We sub-class multiprocessing.pool.Pool instead of multiprocessing.Pool
+# because the latter is only a wrapper function, not a proper class.
+class MyPool(multiprocessing.pool.Pool):
+    Process = NoDaemonProcess
+
+
+def sleepawhile(t):
+    print("Sleeping %i seconds..." % t)
+    time.sleep(t)
+    return t
+
+
+def work(num_procs):
+    print("Creating %i (daemon) workers and jobs in child." % num_procs)
+    pool = multiprocessing.Pool(num_procs)
+
+    result = pool.map(sleepawhile, [randint(1, 5) for x in range(num_procs)])
+
+    # The following is not really needed, since the (daemon) workers of the
+    # child's pool are killed when the child is terminated, but it's good
+    # practice to cleanup after ourselves anyway.
+    pool.close()
+    pool.join()
+    return result
+
+
+def test():
+    print("Creating 5 (non-daemon) workers and jobs in main process.")
+    pool = MyPool(5)
+
+    result = pool.map(work, [randint(1, 5) for x in range(5)])
+
+    pool.close()
+    pool.join()
+    print(result)
+
+
+if __name__ == "__main__":
+    test()