Bug 1289525 - Shrink the TextureClientPool to maximum size after a short delay, and clear the pool after a longer delay r=jrmuizel

gfx/layers/client/TextureClientPool.cpp

@@ -19,11 +19,30 @@
 namespace mozilla {
 namespace layers {
 
+// We want to shrink to our maximum size of N unused tiles
+// after a timeout to allow for short-term budget requirements
+static void
+ShrinkCallback(nsITimer *aTimer, void *aClosure)
+{
+  static_cast<TextureClientPool*>(aClosure)->ShrinkToMaximumSize();
+}
+
+// After a certain amount of inactivity, let's clear the pool so that
+// we don't hold onto tiles needlessly. In general, allocations are
+// cheap enough that re-allocating isn't an issue unless we're allocating
+// at an inopportune time (e.g. mid-animation).
+static void
+ClearCallback(nsITimer *aTimer, void *aClosure)
+{
+  static_cast<TextureClientPool*>(aClosure)->Clear();
+}
 
 TextureClientPool::TextureClientPool(LayersBackend aLayersBackend,
                                      gfx::SurfaceFormat aFormat,
                                      gfx::IntSize aSize,
                                      TextureFlags aFlags,
+                                     uint32_t aShrinkTimeoutMsec,
+                                     uint32_t aClearTimeoutMsec,
                                      uint32_t aInitialPoolSize,
                                      uint32_t aPoolUnusedSize,
                                      TextureForwarder* aAllocator)
@@ -31,6 +50,8 @@ TextureClientPool::TextureClientPool(LayersBackend aLayersBackend,
   , mFormat(aFormat)
   , mSize(aSize)
   , mFlags(aFlags)
+  , mShrinkTimeoutMsec(aShrinkTimeoutMsec)
+  , mClearTimeoutMsec(aClearTimeoutMsec)
   , mInitialPoolSize(aInitialPoolSize)
   , mPoolUnusedSize(aPoolUnusedSize)
   , mOutstandingClients(0)
@@ -39,7 +60,8 @@ TextureClientPool::TextureClientPool(LayersBackend aLayersBackend,
 {
   TCP_LOG("TexturePool %p created with maximum unused texture clients %u\n",
       this, mInitialPoolSize);
-  mTimer = do_CreateInstance("@mozilla.org/timer;1");
+  mShrinkTimer = do_CreateInstance("@mozilla.org/timer;1");
+  mClearTimer = do_CreateInstance("@mozilla.org/timer;1");
   if (aFormat == gfx::SurfaceFormat::UNKNOWN) {
     gfxWarning() << "Creating texture pool for SurfaceFormat::UNKNOWN format";
   }
@@ -47,7 +69,8 @@ TextureClientPool::TextureClientPool(LayersBackend aLayersBackend,
 
 TextureClientPool::~TextureClientPool()
 {
-  mTimer->Cancel();
+  mShrinkTimer->Cancel();
+  mClearTimer->Cancel();
 }
 
 #ifdef GFX_DEBUG_TRACK_CLIENTS_IN_POOL
@@ -145,6 +168,25 @@ TextureClientPool::AllocateTextureClient()
   }
 }
 
+void
+TextureClientPool::ResetTimers()
+{
+  // Shrink down if we're beyond our maximum size
+  if (mShrinkTimeoutMsec &&
+      mTextureClients.size() + mTextureClientsDeferred.size() > mPoolUnusedSize) {
+    TCP_LOG("TexturePool %p scheduling a shrink-to-max-size\n", this);
+    mShrinkTimer->InitWithFuncCallback(ShrinkCallback, this, mShrinkTimeoutMsec,
+                                       nsITimer::TYPE_ONE_SHOT);
+  }
+
+  // Clear pool after a period of inactivity to reduce memory consumption
+  if (mClearTimeoutMsec) {
+    TCP_LOG("TexturePool %p scheduling a clear\n", this);
+    mClearTimer->InitWithFuncCallback(ClearCallback, this, mClearTimeoutMsec,
+                                      nsITimer::TYPE_ONE_SHOT);
+  }
+}
+
 void
 TextureClientPool::ReturnTextureClient(TextureClient *aClient)
 {
@@ -162,8 +204,7 @@ TextureClientPool::ReturnTextureClient(TextureClient *aClient)
   TCP_LOG("TexturePool %p had client %p returned; size %u outstanding %u\n",
       this, aClient, mTextureClients.size(), mOutstandingClients);
 
-  // Shrink down if we're beyond our maximum size
-  ShrinkToMaximumSize();
+  ResetTimers();
 }
 
 void
@@ -180,7 +221,8 @@ TextureClientPool::ReturnTextureClientDeferred(TextureClient* aClient)
   mTextureClientsDeferred.push_back(aClient);
   TCP_LOG("TexturePool %p had client %p defer-returned, size %u outstanding %u\n",
       this, aClient, mTextureClientsDeferred.size(), mOutstandingClients);
-  ShrinkToMaximumSize();
+
+  ResetTimers();
 }
 
 void

gfx/layers/client/TextureClientPool.h

@@ -48,6 +48,8 @@ public:
                     gfx::SurfaceFormat aFormat,
                     gfx::IntSize aSize,
                     TextureFlags aFlags,
+                    uint32_t aShrinkTimeoutMsec,
+                    uint32_t aClearTimeoutMsec,
                     uint32_t aInitialPoolSize,
                     uint32_t aPoolUnusedSize,
                     TextureForwarder* aAllocator);
@@ -114,6 +116,9 @@ private:
   /// Allocate a single TextureClient to be returned from the pool.
   void AllocateTextureClient();
 
+  /// Reset and/or initialise timers for shrinking/clearing the pool.
+  void ResetTimers();
+
   /// Backend passed to the TextureClient for buffer creation.
   LayersBackend mBackend;
 
@@ -126,6 +131,14 @@ private:
   /// Flags passed to the TextureClient for buffer creation.
   const TextureFlags mFlags;
 
+  /// How long to wait after a TextureClient is returned before trying
+  /// to shrink the pool to its maximum size of mPoolUnusedSize.
+  uint32_t mShrinkTimeoutMsec;
+
+  /// How long to wait after a TextureClient is returned before trying
+  /// to clear the pool.
+  uint32_t mClearTimeoutMsec;
+
   // The initial number of unused texture clients to seed the pool with
   // on construction
   uint32_t mInitialPoolSize;
@@ -145,7 +158,8 @@ private:
   std::stack<RefPtr<TextureClient> > mTextureClients;
 
   std::list<RefPtr<TextureClient>> mTextureClientsDeferred;
-  RefPtr<nsITimer> mTimer;
+  RefPtr<nsITimer> mShrinkTimer;
+  RefPtr<nsITimer> mClearTimer;
   // This mSurfaceAllocator owns us, so no need to hold a ref to it
   TextureForwarder* mSurfaceAllocator;
 

gfx/layers/ipc/CompositorBridgeChild.cpp

@@ -932,6 +932,8 @@ CompositorBridgeChild::GetTexturePool(LayersBackend aBackend,
       new TextureClientPool(aBackend, aFormat,
                             gfx::gfxVars::TileSize(),
                             aFlags,
+                            gfxPrefs::LayersTilePoolShrinkTimeout(),
+                            gfxPrefs::LayersTilePoolClearTimeout(),
                             gfxPrefs::LayersTileInitialPoolSize(),
                             gfxPrefs::LayersTilePoolUnusedSize(),
                             this));

gfx/thebes/gfxPrefs.h

@@ -505,6 +505,8 @@ private:
   DECL_GFX_PREF(Once, "layers.tile-height",                    LayersTileHeight, int32_t, 256);
   DECL_GFX_PREF(Once, "layers.tile-initial-pool-size",         LayersTileInitialPoolSize, uint32_t, (uint32_t)50);
   DECL_GFX_PREF(Once, "layers.tile-pool-unused-size",          LayersTilePoolUnusedSize, uint32_t, (uint32_t)10);
+  DECL_GFX_PREF(Once, "layers.tile-pool-shrink-timeout",       LayersTilePoolShrinkTimeout, uint32_t, (uint32_t)50);
+  DECL_GFX_PREF(Once, "layers.tile-pool-clear-timeout",        LayersTilePoolClearTimeout, uint32_t, (uint32_t)5000);
   DECL_GFX_PREF(Once, "layers.tiles.adjust",                   LayersTilesAdjust, bool, true);
   DECL_GFX_PREF(Once, "layers.tiles.edge-padding",             TileEdgePaddingEnabled, bool, true);
   DECL_GFX_PREF(Live, "layers.tiles.fade-in.enabled",          LayerTileFadeInEnabled, bool, false);