cc: Set the mapped memory reclaim limit for the renderer compositor on Android

cc/resources/pixel_buffer_raster_worker_pool.cc

Index: cc/resources/pixel_buffer_raster_worker_pool.cc
diff --git a/cc/resources/pixel_buffer_raster_worker_pool.cc b/cc/resources/pixel_buffer_raster_worker_pool.cc
index 5685b609a1920cbc3bcf4c5bb5486fea41a01539..22e796d7ef4f89119cc44bfdb4f600f14d81f64f 100644
--- a/cc/resources/pixel_buffer_raster_worker_pool.cc
+++ b/cc/resources/pixel_buffer_raster_worker_pool.cc
@@ -4,6 +4,8 @@
 
 #include "cc/resources/pixel_buffer_raster_worker_pool.h"
 
+#include <limits>
+
 #include "base/containers/stack_container.h"
 #include "base/debug/trace_event.h"
 #include "base/values.h"
@@ -94,7 +96,8 @@ bool WasCanceled(const internal::RasterWorkerPoolTask* task) {
 
 PixelBufferRasterWorkerPool::PixelBufferRasterWorkerPool(
     ResourceProvider* resource_provider,
-    size_t num_threads)
+    size_t num_threads,
+    ContextProvider* context_provider)
     : RasterWorkerPool(resource_provider, num_threads),
       shutdown_(false),
       scheduled_raster_task_count_(0),
@@ -104,25 +107,14 @@ PixelBufferRasterWorkerPool::PixelBufferRasterWorkerPool(
       should_notify_client_if_no_tasks_are_pending_(false),
       should_notify_client_if_no_tasks_required_for_activation_are_pending_(
           false) {
-// If we raster too fast we become upload bound, and pending
-// uploads consume memory. For maximum upload throughput, we would
-// want to allow for upload_throughput * pipeline_time of pending
-// uploads, after which we are just wasting memory. Since we don't
-// know our upload throughput yet, this just caps our memory usage.
-#if defined(OS_ANDROID)
-  size_t divider = 1;
-  if (base::android::SysUtils::IsLowEndDevice())
-    divider = 3;
-
-  // For reference Nexus10 can upload 1MB in about 2.5ms.
-  const size_t kMaxBytesUploadedPerMs = (2 * 1024 * 1024) / (5 * divider);
-#else
-  // For reference Chromebook Pixel can upload 1MB in about 0.5ms.
-  const size_t kMaxBytesUploadedPerMs = 1024 * 1024 * 2;
-#endif
-
-  // Assuming a two frame deep pipeline.
-  max_bytes_pending_upload_ = 16 * 2 * kMaxBytesUploadedPerMs;
+  if (context_provider != NULL) {
+    max_bytes_pending_upload_ =
+        context_provider->ContextCapabilities().max_transfer_buffer_usage_bytes;
+  } else {
+    // For unit tests:

[danakj, 2013/08/29 20:10:28]

// Software compositing should not use this path in production. Just use a
default value when testing this path with software compositor.

[danakj, 2013/08/29 20:10:28]

reveman@ can we #if !defined(UNIT_TEST) => NOT_REACHED(); ?

If not, can we TODO() to do that?

[kaanb, 2013/08/30 01:11:35]

Done.

+    // TODO(kaanb): make this a static const somewhere?

[danakj, 2013/08/29 20:10:28]

No idea where. If reveman@ has an idea let's do that, otherwise I think just
drop the TODO.

[kaanb, 2013/08/30 01:11:35]

Done.

+    max_bytes_pending_upload_ = std::numeric_limits<size_t>::max();
+  }
 }
 
 PixelBufferRasterWorkerPool::~PixelBufferRasterWorkerPool() {