Changeset 86524 in webkit

Timestamp:

May 15, 2011 10:31:12 PM (13 years ago)

Author:

msaboff@apple.com

Message:

2011-05-15 Michael Saboff <​msaboff@apple.com>

Reviewed by Geoffrey Garen.

Suboptimal lifetime of BackingStore objects in DrawingAreaProxyImpl
​https://bugs.webkit.org/show_bug.cgi?id=60864

Implemented reuse of BackingStore's in
DrawingAreaProxyImpl::didUpdateBackingStoreState when the size needed
matches the size of the existing BackingStore.
Also reduced the discardBackingStoreTimer from 5 to 2 seconds.
These changes reduces memory usage up to 10MB on memory tests.

• UIProcess/DrawingAreaProxyImpl.cpp: (WebKit::DrawingAreaProxyImpl::didUpdateBackingStoreState): (WebKit::DrawingAreaProxyImpl::discardBackingStoreSoon):

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• UIProcess/DrawingAreaProxyImpl.cpp (modified) (2 diffs)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2011-05-15  Michael Saboff  <msaboff@apple.com>
+
+        Reviewed by Geoffrey Garen.
+
+        Suboptimal lifetime of BackingStore objects in DrawingAreaProxyImpl
+        https://bugs.webkit.org/show_bug.cgi?id=60864
+
+        Implemented reuse of BackingStore's in 
+        DrawingAreaProxyImpl::didUpdateBackingStoreState when the size needed
+        matches the size of the existing BackingStore.
+        Also reduced the discardBackingStoreTimer from 5 to 2 seconds.
+        These changes reduces memory usage up to 10MB on memory tests.
+
+        * UIProcess/DrawingAreaProxyImpl.cpp:
+        (WebKit::DrawingAreaProxyImpl::didUpdateBackingStoreState):
+        (WebKit::DrawingAreaProxyImpl::discardBackingStoreSoon):
+
 2011-05-15  Anders Carlsson  <andersca@apple.com>
 

trunk/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp

@@ -215 +215 @@
 #endif
 
-    // FIXME: We could just reuse our existing backing store if it's the same size as
-    // updateInfo.viewSize.
-    m_backingStore = nullptr;
+    // If we have a backing store the right size, reuse it.
+    if (m_backingStore && m_backingStore->size() != updateInfo.viewSize)
+        m_backingStore = nullptr;
     incorporateUpdate(updateInfo);
 }
@@ -358 +358 @@
     // We'll wait this many seconds after the last paint before throwing away our backing store to save memory.
     // FIXME: It would be smarter to make this delay based on how expensive painting is. See <http://webkit.org/b/55733>.
-    static const double discardBackingStoreDelay = 5;
+    static const double discardBackingStoreDelay = 2;
 
     m_discardBackingStoreTimer.startOneShot(discardBackingStoreDelay);