[svn r134] Fixes for some interesting issues discovered only after our count of unit tests using database connections crested 100.

eventlet/coros.py

@@ -423,14 +423,30 @@ class CoroutinePool(pools.Pool):
         try:
             while True:
                 recvd = sender.wait()
+                # Delete the sender's result here because the very
+                # first event through the loop is referenced by
+                # spawn_startup, and therefore is not itself deleted.
+                # This means that we have to free up its argument
+                # because otherwise said argument persists in memory
+                # forever.  This is generally only a problem in unit
+                # tests.
+                sender._result = NOT_USED
+                
                 sender = event()
                 (evt, func, args, kw) = recvd
                 self._safe_apply(evt, func, args, kw)
+                # Likewise, delete these variables or else they will
+                # be referenced by this frame until replaced by the
+                # next recvd, which may or may not be a long time from
+                # now.
+                del evt, func, args, kw, recvd
+
                 api.get_hub().runloop.cancel_timers(api.getcurrent())
                 self.put(sender)
         finally:
             # if we get here, something broke badly, and all we can really
-            # do is try to keep the pool from leaking items
+            # do is try to keep the pool from leaking items.
+            # Shouldn't even try to print the exception.
             self.put(self.create())
             
     def _safe_apply(self, evt, func, args, kw):

eventlet/db_pool.py

@@ -91,6 +91,8 @@ class BaseConnectionPool(Pool):
         # it's dead or None
         try:
             conn.rollback()
+        except KeyboardInterrupt:
+            raise
         except AttributeError, e:
             # this means it's already been destroyed, so we don't need to print anything
             conn = None
@@ -114,6 +116,20 @@ class BaseConnectionPool(Pool):
         else:
             self.current_size -= 1
 
+    def clear(self):
+        """ Close all connections that this pool still holds a reference to, leaving it empty."""
+        for conn in self.free_items:
+            try:
+                conn.close()
+            except KeyboardInterrupt:
+                raise
+            except:
+                pass   # even if stuff happens here, we still want to at least try to close all the other connections
+        self.free_items.clear()
+            
+    def __del__(self):
+        self.clear()
+    
 
 class SaranwrappedConnectionPool(BaseConnectionPool):
     """A pool which gives out saranwrapped database connections from a pool