Disk cache: Increase the throttling threshold (100->460ms) for...

net/disk_cache/backend_impl.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/disk_cache/backend_impl.h"
 
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/message_loop.h"
 #include "base/metrics/field_trial.h"
@@ skipping 1123 matching lines @@
   if (cache_type() != net::DISK_CACHE)
     return;
 
   UMA_HISTOGRAM_TIMES(base::FieldTrial::MakeName("DiskCache.TotalIOTime",
                                                  "CacheThrottle").data(),
                       elapsed_time);
 
   if (!throttle_requests_)
     return;
 
-  const int kMaxNormalDelayMS = 100;
+  const int kMaxNormalDelayMS = 460;
 
   bool throttling = io_delay_ > kMaxNormalDelayMS;
 
   // We keep a simple exponential average of elapsed_time.
   io_delay_ = (io_delay_ + static_cast<int>(elapsed_time.InMilliseconds())) / 2;
   if (io_delay_ > kMaxNormalDelayMS && !throttling)
     background_queue_.StartQueingOperations();
   else if (io_delay_ <= kMaxNormalDelayMS && throttling)
     background_queue_.StopQueingOperations();
 }
@@ skipping 940 matching lines @@
     if (total_memory > kMaxBuffersSize || total_memory <= 0)
       total_memory = kMaxBuffersSize;
 
     done = true;
   }
 
   return static_cast<int>(total_memory);
 }
 
 }  // namespace disk_cache