request-wrapper: add gc.collect to every 25th request to clear up memory.

- we've indicated that general GC isn't so efficient. Manually triggering it would save lots of memory.

vcsserver/tweens/request_wrapper.py

@@ -15,8 +15,7 b''
 # along with this program; if not, write to the Free Software Foundation,
 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
-
-
+import gc
 import time
 import logging
 
@@ -40,6 +39,7 b' class RequestWrapperTween(object):'
     def __init__(self, handler, registry):
         self.handler = handler
         self.registry = registry
+        self.gc_max_requests = 25
 
         # one-time configuration code goes here
 
@@ -56,6 +56,10 b' class RequestWrapperTween(object):'
                 count, '127.0.0.1', request.environ.get('REQUEST_METHOD'),
                 safe_str(get_access_path(request)), total, get_user_agent(request.environ))
 
+        if self.gc_max_requests and count % self.gc_max_requests == 0:
+            log.info('Performing gc.collect now')
+            gc.collect()
+
         return response