Disable instrumentation for disabled panels.

This eliminates the performance overhead when a panel is disabled.

1 files changed, 6 insertions, 4 deletions

diff --git a/debug_toolbar/middleware.py b/debug_toolbar/middleware.py
index 4f5b9bd..80e9305 100644
--- a/debug_toolbar/middleware.py
+++ b/debug_toolbar/middleware.py
@@ -95,6 +95,7 @@ class DebugToolbarMiddleware(object):
                 panel.enabled = panel.dom_id() not in request.COOKIES
                 if not panel.enabled:
                     continue
+                panel.enable_instrumentation()
                 panel.process_request(request)
             self.__class__.debug_toolbars[threading.current_thread().ident] = toolbar
 
@@ -130,12 +131,13 @@ class DebugToolbarMiddleware(object):
                     {'redirect_to': redirect_to}
                 )
                 response.cookies = cookies
+        for panel in toolbar.panels:
+            if not panel.enabled:
+                continue
+            panel.process_response(request, response)
+            panel.disable_instrumentation()
         if ('gzip' not in response.get('Content-Encoding', '') and
                 response.get('Content-Type', '').split(';')[0] in _HTML_TYPES):
-            for panel in toolbar.panels:
-                if not panel.enabled:
-                    continue
-                panel.process_response(request, response)
             response.content = replace_insensitive(
                 force_text(response.content, encoding=settings.DEFAULT_CHARSET),
                 self.tag,