From cf7b4e74f08c6eb5542fe4584c09504d7862651e Mon Sep 17 00:00:00 2001
From: Andy Street <andrews@fb.com>
Date: Wed, 29 Jun 2016 13:59:43 -0700
Subject: [PATCH] Use DISPLAY thread priority for main thread in React Native

Summary: In older versions of android, the main thread is given the same priority as all other threads (default). Instead, it should have a higher priority (DISPLAY) which will make sure it's scheduled instead of the background JS/native modules threads.

Reviewed By: majak

Differential Revision: D3497244

fbshipit-source-id: 15ab09f4ebcad2692ae1261f15aa2c6c39f72ee9
---
 .../facebook/react/bridge/queue/MessageQueueThreadImpl.java    | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueThreadImpl.java b/ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueThreadImpl.java
index 318765b69c2..4687fc140b4 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueThreadImpl.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/bridge/queue/MessageQueueThreadImpl.java
@@ -13,6 +13,7 @@ import java.util.concurrent.Callable;
 import java.util.concurrent.Future;
 
 import android.os.Looper;
+import android.os.Process;
 
 import com.facebook.common.logging.FLog;
 import com.facebook.proguard.annotations.DoNotStrip;
@@ -148,12 +149,14 @@ public class MessageQueueThreadImpl implements MessageQueueThread {
         new MessageQueueThreadImpl(name, mainLooper, exceptionHandler);
 
     if (UiThreadUtil.isOnUiThread()) {
+      Process.setThreadPriority(Process.THREAD_PRIORITY_DISPLAY);
       MessageQueueThreadRegistry.register(mqt);
     } else {
       UiThreadUtil.runOnUiThread(
           new Runnable() {
             @Override
             public void run() {
+              Process.setThreadPriority(Process.THREAD_PRIORITY_DISPLAY);
               MessageQueueThreadRegistry.register(mqt);
             }
           });