Changeset 197254 in webkit

Timestamp:

Feb 27, 2016 9:49:29 AM (8 years ago)

Author:

akling@apple.com

Message:

[iOS] Discard decoded image data on top-level navigation.
<​https://webkit.org/b/154776>

Reviewed by Anders Carlsson.

Add a mechanism that destroys decoded data for all CachedImages and invoke it
when performing a top-level navigation on iOS.

This substantially reduces the ImageIO contribution to our peak memory footprint.

It would be even better if we could mark these images volatile during the transition
but we currently don't have framework support for such machinations.

• loader/FrameLoader.cpp:

(WebCore::FrameLoader::commitProvisionalLoad):

• loader/cache/MemoryCache.cpp:

(WebCore::MemoryCache::forEachResource):
(WebCore::MemoryCache::destroyDecodedDataForAllImages):

• loader/cache/MemoryCache.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• loader/FrameLoader.cpp (modified) (1 diff)
• loader/cache/MemoryCache.cpp (modified) (1 diff)
• loader/cache/MemoryCache.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2016-02-27  Andreas Kling  <akling@apple.com>
+
+        [iOS] Discard decoded image data on top-level navigation.
+        <https://webkit.org/b/154776>
+
+        Reviewed by Anders Carlsson.
+
+        Add a mechanism that destroys decoded data for all CachedImages and invoke it
+        when performing a top-level navigation on iOS.
+
+        This substantially reduces the ImageIO contribution to our peak memory footprint.
+
+        It would be even better if we could mark these images volatile during the transition
+        but we currently don't have framework support for such machinations.
+
+        * loader/FrameLoader.cpp:
+        (WebCore::FrameLoader::commitProvisionalLoad):
+        * loader/cache/MemoryCache.cpp:
+        (WebCore::MemoryCache::forEachResource):
+        (WebCore::MemoryCache::destroyDecodedDataForAllImages):
+        * loader/cache/MemoryCache.h:
+
 2016-02-26  Carlos Garcia Campos  <cgarcia@igalia.com>
 

trunk/Source/WebCore/loader/FrameLoader.cpp

@@ -1767 +1767 @@
         // outweigh the cost of recompiling in the case of a future backwards navigation.
         GCController::singleton().deleteAllLinkedCode();
+
+        // Throw out decoded data for CachedImages when we are switching pages. The majority of it
+        // will not be used by the next page.
+        MemoryCache::singleton().destroyDecodedDataForAllImages();
 #endif
     }

trunk/Source/WebCore/loader/cache/MemoryCache.cpp

@@ -278 +278 @@
 }
 
+void MemoryCache::forEachResource(const std::function<void(CachedResource&)>& function)
+{
+    for (auto& lruList : m_allResources) {
+        for (auto& resource : *lruList)
+            function(*resource);
+    }
+}
+
+void MemoryCache::destroyDecodedDataForAllImages()
+{
+    MemoryCache::singleton().forEachResource([](CachedResource& resource) {
+        if (resource.isImage())
+            resource.destroyDecodedData();
+    });
+}
+
 void MemoryCache::pruneLiveResourcesToSize(unsigned targetSize, bool shouldDestroyDecodedDataForAllLiveResources)
 {

trunk/Source/WebCore/loader/cache/MemoryCache.h

@@ -102 +102 @@
     void revalidationSucceeded(CachedResource& revalidatingResource, const ResourceResponse&);
     void revalidationFailed(CachedResource& revalidatingResource);
+
+    void forEachResource(const std::function<void(CachedResource&)>&);
+    void destroyDecodedDataForAllImages();
     
     // Sets the cache's memory capacities, in bytes. These will hold only approximately,