Checkpoint the shmlog before we wait for a reply from the backend.

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@3296 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_fetch.c

@@ -362,6 +362,9 @@ Fetch(struct sess *sp)
 		return (__LINE__);
 	}
 
+	/* Checkpoint the shmlog here */
+	WSL_Flush(w, 0);
+
 	/* XXX is this the right place? */
 	VSL_stats->backend_req++;