Prioritize which HTTP requests get a socket first by adding a priority level ...

chrome/browser/renderer_host/resource_dispatcher_host.cc

 // Copyright (c) 2006-2008 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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "chrome/browser/renderer_host/resource_dispatcher_host.h"
 
 #include <vector>
 
@@ skipping 35 matching lines @@
 // TODO(port): Move these includes to the above section when porting is done.
 #if defined(OS_POSIX)
 #include "chrome/common/temp_scaffolding_stubs.h"
 #elif defined(OS_WIN)
 #include "chrome/browser/login_prompt.h"
 #include "chrome/browser/renderer_host/render_view_host_delegate.h"
 #include "chrome/browser/safe_browsing/safe_browsing_service.h"
 #endif
 
 // Uncomment to enable logging of request traffic.
-//#define LOG_RESOURCE_DISPATCHER_REQUESTS
+// #define LOG_RESOURCE_DISPATCHER_REQUESTS
 
 #ifdef LOG_RESOURCE_DISPATCHER_REQUESTS
 # define RESOURCE_LOG(stuff) LOG(INFO) << stuff
 #else
 # define RESOURCE_LOG(stuff)
 #endif
 
 using base::Time;
 using base::TimeDelta;
 using base::TimeTicks;
@@ skipping 254 matching lines @@
   // Construct the request.
   URLRequest* request = new URLRequest(request_data.url, this);
   request->set_method(request_data.method);
   request->set_policy_url(request_data.policy_url);
   request->set_referrer(request_data.referrer.spec());
   request->SetExtraRequestHeaders(request_data.headers);
   request->set_load_flags(request_data.load_flags);
   request->set_context(context);
   request->set_origin_pid(request_data.origin_pid);
 
+  // If the request is for the top level page or a frame/iframe, then we should
+  // prioritize it higher than other resource types.  Currently, we just use
+  // priorities 1 and 0.
+  // TODO(willchan): Revisit the actual priorities when looking at considering
+  // boosting priorities for requests for the foreground tab.
+  if (request_data.resource_type == ResourceType::MAIN_FRAME ||
+      request_data.resource_type == ResourceType::SUB_FRAME) {
+    request->set_priority(1);
+  } else {
+    request->set_priority(0);
+  }
+
   // Set upload data.
   uint64 upload_size = 0;
   if (!request_data.upload_content.empty()) {
     scoped_refptr<net::UploadData> upload = new net::UploadData();
     upload->set_elements(request_data.upload_content);  // Deep copy.
     request->set_upload(upload);
     upload_size = upload->GetContentLength();
   }
 
   // Install a CrossSiteResourceHandler if this request is coming from a
@@ skipping 29 matching lines @@
   ExtraRequestInfo* extra_info =
       new ExtraRequestInfo(handler,
                            process_type,
                            process_id,
                            route_id,
                            request_id,
                            request_data.frame_origin,
                            request_data.main_frame_origin,
                            request_data.resource_type,
                            upload_size);
-  extra_info->allow_download = ResourceType::IsFrame(request_data.resource_type);
+  extra_info->allow_download =
+      ResourceType::IsFrame(request_data.resource_type);
   request->set_user_data(extra_info);  // takes pointer ownership
 
   BeginRequestInternal(request);
 }
 
 void ResourceDispatcherHost::OnDataReceivedACK(int request_id) {
   DataReceivedACK(receiver_->GetProcessId(), request_id);
 }
 
 void ResourceDispatcherHost::DataReceivedACK(int process_id, int request_id) {
@@ skipping 113 matching lines @@
 
   ExtraRequestInfo* extra_info =
       new ExtraRequestInfo(handler,
                            ChildProcessInfo::RENDER_PROCESS,
                            process_id,
                            route_id,
                            request_id_,
                            "null",  // frame_origin
                            "null",  // main_frame_origin
                            ResourceType::SUB_RESOURCE,
-                           0 /* upload_size */ );
+                           0 /* upload_size */);
   extra_info->allow_download = true;
   extra_info->is_download = true;
   request->set_user_data(extra_info);  // Takes pointer ownership.
 
   BeginRequestInternal(request);
 }
 
 // This function is only used for saving feature.
 void ResourceDispatcherHost::BeginSaveFile(const GURL& url,
                                            const GURL& referrer,
@@ skipping 1002 matching lines @@
     case ViewHostMsg_UploadProgress_ACK::ID:
     case ViewHostMsg_SyncLoad::ID:
       return true;
 
     default:
       break;
   }
 
   return false;
 }