Automatically start the GPU process 5s after browser startup.

content/browser/browser_main_loop.cc

Index: content/browser/browser_main_loop.cc
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index af21209e88cb3c6c95ad9991d8a4dc129a037eca..bca8b971d6763ddea36a0a264fcbcf12c96a16b4 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -12,11 +12,13 @@
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"

[jam, 2012/03/01 06:13:02]

not needed?

[Ami GONE FROM CHROMIUM, 2012/03/01 16:03:59]

Done.

 #include "base/threading/thread_restrictions.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/browser/download/download_file_manager.h"
 #include "content/browser/download/save_file_manager.h"
 #include "content/browser/gpu/browser_gpu_channel_host_factory.h"
+#include "content/browser/gpu/gpu_process_host.h"
 #include "content/browser/gpu/gpu_process_host_ui_shim.h"
 #include "content/browser/in_process_webkit/webkit_thread.h"
 #include "content/browser/plugin_service_impl.h"
@@ -429,6 +431,14 @@ void BrowserMainLoop::CreateThreads() {
   // If the UI thread blocks, the whole UI is unresponsive.
   // Do not allow disk IO from the UI thread.
   base::ThreadRestrictions::SetIOAllowed(false);
+
+  BrowserThread::PostDelayedTask(
+      BrowserThread::IO, FROM_HERE, base::Bind(
+          base::IgnoreResult(&GpuProcessHost::GetForClient),
+          1,  // Arbitrary non-0 (to cause sandboxing) client_id.

[apatrick_chromium, 2012/03/01 00:26:21]

I had a plan at some point to have a pool of GPU processes but I think that will
never happen with the direction Aura is going. Not for this CL but GetForClient
should just take an argument indicating whether to return the sandboxed or
unsandboxed GPU process. I'll do it.

+          content::CAUSE_FOR_GPU_LAUNCH_BROWSER_STARTUP),
+      // Arbitrary delay to avoid allow browser init precious CPU cycles.
+      base::TimeDelta::FromSeconds(5));
 }
 
 void BrowserMainLoop::RunMainMessageLoopParts() {