cc: Never block on uploads from previous frame and increase max pending uploads.

cc/CCTextureUpdateController.cpp

 // Copyright 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.
 
 #include "config.h"
 
 #include "CCTextureUpdateController.h"
 
 #include "GraphicsContext3D.h"
 #include "TextureCopier.h"
 #include "TextureUploader.h"
 #include "TraceEvent.h"
 #include <limits>
 #include <wtf/CurrentTime.h>
 
 namespace {
 
 // Number of partial updates we allow.
 static const size_t partialTextureUpdatesMax = 12;
 
 // Measured in seconds.
 static const double textureUpdateTickRate = 0.004;
 
 // Measured in seconds.
 static const double uploaderBusyTickRate = 0.001;
 
 // Flush interval when performing texture uploads.
 static const int textureUploadFlushPeriod = 4;
 
-// Number of pending update intervals to allow.
-static const size_t maxPendingUpdateIntervals = 2;
+// Number of blocking update intervals to allow.
+static const size_t maxBlockingUpdateIntervals = 4;
 
 } // anonymous namespace
 
 namespace cc {
 
 size_t CCTextureUpdateController::maxPartialTextureUpdates()
 {
     return partialTextureUpdatesMax;
 }
 
@@ skipping 98 matching lines @@
 base::TimeDelta CCTextureUpdateController::updateMoreTexturesTime() const
 {
     return base::TimeDelta::FromMilliseconds(textureUpdateTickRate * 1000);
 }
 
 size_t CCTextureUpdateController::updateMoreTexturesSize() const
 {
     return m_textureUpdatesPerTick;
 }
 
-size_t CCTextureUpdateController::maxPendingUpdates() const
+size_t CCTextureUpdateController::maxBlockingUpdates() const
 {
-    return updateMoreTexturesSize() * maxPendingUpdateIntervals;
+    return updateMoreTexturesSize() * maxBlockingUpdateIntervals;
 }
 
 bool CCTextureUpdateController::updateMoreTexturesIfEnoughTimeRemaining()
 {
-    // Pending uploads will increase when we're too aggressive in our upload
+    // Blocking uploads will increase when we're too aggressive in our upload
     // time estimate. We use a different timeout here to prevent unnecessary
-    // amounts of idle time when pending uploads have reached the max.
-    if (m_uploader->numPendingUploads() >= maxPendingUpdates()) {
+    // amounts of idle time when blocking uploads have reached the max.
+    if (m_uploader->numBlockingUploads() >= maxBlockingUpdates()) {
         m_timer->startOneShot(uploaderBusyTickRate);
         return true;
     }
 
     if (!m_queue->fullUploadSize())
         return false;
 
     bool hasTimeRemaining = m_timeLimit.is_null() ||
         this->now() < m_timeLimit - updateMoreTexturesTime();
     if (hasTimeRemaining)
@@ skipping 19 matching lines @@
         if (!(uploadCount % textureUploadFlushPeriod) && uploadCount)
             m_resourceProvider->shallowFlushIfSupported();
         m_uploader->uploadTexture(m_resourceProvider, m_queue->takeFirstFullUpload());
         uploadCount++;
     }
     m_uploader->endUploads();
     m_resourceProvider->shallowFlushIfSupported();
 }
 
 }