Per-host V8 histograms.

content/renderer/render_thread_impl.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 220 matching lines @@
   WebGraphicsContext3DCommandBufferImpl* GetGpuVDAContext3D();
 
   // Handle loss of the shared GpuVDAContext3D context above.
   static void OnGpuVDAContextLoss();
 
   // AudioRendererMixerManager instance which manages renderer side mixer
   // instances shared based on configured audio parameters.  Lazily created on
   // first call.
   content::AudioRendererMixerManager* GetAudioRendererMixerManager();
 
+  // For producing custom V8 histograms. Custom histograms are produced if all
+  // RenderViews share the same host, and the host is in the pre-specified set
+  // of hosts we want to produce custom diagrams for. The name for a custom
+  // diagram is the name of the corresponding generic diagram plus a
+  // host-specific suffix.
+  class CONTENT_EXPORT HistogramCustomizer {
+   public:
+    HistogramCustomizer();
+    ~HistogramCustomizer();
+
+    // Called when a top frame of a RenderView navigates. This function updates
+    // RenderThreadImpl's information about whether all RenderViews are
+    // displaying a page from the same host. |host| is the host where a
+    // RenderView navigated, and |view_count| is the number of RenderViews in
+    // this process.
+    void RenderViewNavigatedToHost(const std::string& host, size_t view_count);
+
+    // Used for customizing some histograms if all RenderViews share the same
+    // host. Returns the current custom histogram name to use for
+    // |histogram_name|, or |histogram_name| if it shouldn't be customized.
+    std::string ConvertToCustomHistogramName(const char* histogram_name) const;
+
+   private:
+    friend class RenderThreadImplUnittest;
+
+    // Used for updating the information on which is the common host which all
+    // RenderView's share (if any). If there is no common host, this function is
+    // called with an empty string.
+    void SetCommonHost(const std::string& host);
+
+    // The current common host of the RenderViews; empty string if there is no
+    // common host.
+    std::string common_host_;
+    // The corresponding suffix.
+    std::string common_host_histogram_suffix_;
+    // Set of histograms for which we want to produce a custom histogram if
+    // possible.
+    std::set<std::string> custom_histograms_;
+
+    DISALLOW_COPY_AND_ASSIGN(HistogramCustomizer);
+  };
+
+  HistogramCustomizer* histogram_customizer() {
+    return &histogram_customizer_;
+  }
+
  private:
   virtual bool OnControlMessageReceived(const IPC::Message& msg) OVERRIDE;
 
   void Init();
 
   void OnSetZoomLevelForCurrentURL(const std::string& host, double zoom_level);
   void OnSetCSSColors(const std::vector<CSSColors::CSSColorMapping>& colors);
   void OnCreateNewView(const ViewMsg_New_Params& params);
   void OnTransferBitmap(const SkBitmap& bitmap, int resource_id);
   void OnPurgePluginListCache(bool reload_pages);
@@ skipping 60 matching lines @@
   scoped_ptr<content::old::BrowserPluginRegistry> browser_plugin_registry_;
 
   ObserverList<content::RenderProcessObserver> observers_;
 
   class GpuVDAContextLostCallback;
   scoped_ptr<GpuVDAContextLostCallback> context_lost_cb_;
   scoped_ptr<WebGraphicsContext3DCommandBufferImpl> gpu_vda_context3d_;
 
   scoped_ptr<content::AudioRendererMixerManager> audio_renderer_mixer_manager_;
 
+  HistogramCustomizer histogram_customizer_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_