Changeset 173 in tracdarcs

Timestamp:

05/08/10 21:28:22 (21 months ago)

Author:

lele@…

Hash name:

20100508192822-97f81-b1bb7bbbea66114acc0c79d962bd856ff264cf23

Message:

Optional constraint on the number of concurrent darcs processes
A new option "darcs.max_concurrent_darcses" may set a limit on the
number of concurrent running darcs subprocesses. It is eventually
applied on a per repository basis. By default there are no limits, as
before.

Location:

tracdarcs

Files:

• components.py (modified) (2 diffs)
• command.py (modified) (2 diffs)

tracdarcs/components.py

@@ -37 +37 @@
     darcs_command = Option('darcs', 'command', 'darcs',
                            "Name of the external darcs binary.")
+
+    max_concurrent_darcses = Option('darcs', 'max_concurrent_darcses', 'false',
+                                    "Max number of concurrent darcses running per repository.")
 
     possible_encodings = Option('darcs', 'possible_encodings', 'utf-8,iso8859-1',
@@ -56 +59 @@
             possible_encodings = [e.strip()
                                   for e in self.possible_encodings.split(',')]
+
+        # Setup the semaphore used to limit the number of concurrent running
+        # darcs within a single repository.
+
+        if self.max_concurrent_darcses and int(self.max_concurrent_darcses)>0:
+            from command import DarcsCommand
+            if DarcsCommand.RUNNING_DARCSES is None:
+                from threading import BoundedSemaphore
+                DarcsCommand.RUNNING_DARCSES = BoundedSemaphore(value=int(self.max_concurrent_darcses))
+
         return DarcsRepository(db, dir, self.env.log, darcs, possible_encodings, params)
 

tracdarcs/command.py

@@ -45 +45 @@
     '''
 
+    RUNNING_DARCSES = None
     darcs_version = None
 
@@ -78 +79 @@
         else:
             command = 'TZ=UTC ' + command
-        if self.log:
-            self.log.debug(command)
-        np = NaivePopen(command, input=input, capturestderr=True)
+
+        # Respect the maximum number of running darcs limit
+        if DarcsCommand.RUNNING_DARCSES is not None:
+            if self.log:
+                self.log.debug('Asking permission to run %s ...', command)
+            DarcsCommand.RUNNING_DARCSES.acquire()
+            if self.log:
+                self.log.debug('... got permission to run %s', command)
+        else:
+            if self.log:
+                self.log.debug(command)
+
+        try:
+            np = NaivePopen(command, input=input, capturestderr=True)
+        finally:
+            if DarcsCommand.RUNNING_DARCSES is not None:
+                DarcsCommand.RUNNING_DARCSES.release()
+
         if np.errorlevel:
             err = 'Running (%s) failed: %s, %s: %s' % (command,