[Zodb-checkins] CVS: StandaloneZODB/ZEO - StorageServer.py:1.28.2.2

[Jeremy Hylton]

Update of /cvs-repository/StandaloneZODB/ZEO
In directory cvs.zope.org:/tmp/cvs-serv27064

Modified Files:
      Tag: zeo-1_0-branch
	StorageServer.py 
Log Message:
Avoid long delays at the end of a pack.

When a client calls pack, a separate thread is started to call the
pack call on the storage.  When the thread finishes, it calls
message_output() to send a response to the client.  If asyncore is
currently in a poll call when this happens, the output won't be
detected until the next poll call.  If there is little I/O on the
connection, this won't happen until the select call times out after 30
seconds.

The trigger is the standard gimmick for one thread to notify a
mainloop in another thread that the first thread has some I/O to do.
It exits the current select.  The next poll call detects that the
triggering thread is ready to do I/O and handles it.



=== StandaloneZODB/ZEO/StorageServer.py 1.28.2.1 => 1.28.2.2 ===
 from ZODB.Transaction import Transaction
 import traceback
-from zLOG import LOG, INFO, ERROR, TRACE
+from zLOG import LOG, INFO, ERROR, TRACE, BLATHER
 from ZODB.referencesf import referencesf
 from thread import start_new_thread
 from cStringIO import StringIO
+from ZEO import trigger
 
 class StorageServerError(POSException.StorageError): pass
 
@@ -124,7 +125,6 @@
         self.__connections={}
         self.__get_connections=self.__connections.get
 
-
         asyncore.dispatcher.__init__(self)
 
         if type(connection) is type(''):
@@ -234,6 +234,7 @@
         self.__server=server
         self.__invalidated=[]
         self.__closed=None
+        self._pack_trigger = trigger.trigger()
         if __debug__: debug='ZEO Server'
         else: debug=0
         SizedMessageAsyncConnection.__init__(self, sock, addr, debug=debug)
@@ -384,16 +385,21 @@
         if wait: return _noreturn
 
     def _pack(self, t, wait=0):
-        try: 
+        try:
+            LOG('ZEO Server', BLATHER, 'pack begin')
             self.__storage.pack(t, referencesf)
+            LOG('ZEO Server', BLATHER, 'pack end')
         except:
             LOG('ZEO Server', ERROR,
                 'Pack failed for %s' % self.__storage_id,
                 error=sys.exc_info())
-            if wait: self.return_error(sys.exc_info()[0], sys.exc_info()[1])
+            if wait:
+                self.return_error(sys.exc_info()[0], sys.exc_info()[1])
+                self._pack_trigger.pull_trigger()
         else:
             if wait:
                 self.message_output('RN.')
+                self._pack_trigger.pull_trigger()
             else:
                 # Broadcast new size statistics
                 self.__server.invalidate(0, self.__storage_id, (),