Appium Timed out after 10000 milliseconds waiting for root AccessibilityNodeInfo - appium

Question

Getting the following appium error once in a while and not sure how to solve it. Any way to increase this timeout or help fix this issue? Your help is appreciated.
selenium.common.exceptions.WebDriverException: Message: An unknown server-side error occurred while processing the command. Original error: io.appium.uiautomator2.common.exceptions.UiAutomator2Exception: Timed out after 10000 milliseconds waiting for root AccessibilityNodeInfo
at io.appium.uiautomator2.utils.AXWindowHelpers.refreshRootAXNode(AXWindowHelpers.java:78)
at io.appium.uiautomator2.handler.Source.safeHandle(Source.java:38)
at io.appium.uiautomator2.handler.request.SafeRequestHandler.handle(SafeRequestHandler.java:36)
at io.appium.uiautomator2.server.AppiumServlet.handleRequest(AppiumServlet.java:250)
at io.appium.uiautomator2.server.AppiumServlet.handleHttpRequest(AppiumServlet.java:241)
at io.appium.uiautomator2.http.ServerHandler.channelRead(ServerHandler.java:44)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:435)
at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:293)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:267)
at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:250)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:345)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1294)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:366)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:352)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:911)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:611)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:552)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:466)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:438)
at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:140)
at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144)
at java.lang.Thread.run(Thread.java:764)
../../.ve/qa/lib/python3.7/site-packages/selenium/webdriver/remote/errorhandler.py:242: WebDriverException

Answer 1

There is nothing you can do here actually. The exception you got occurs on system function call:
root = UiAutomatorBridge.getInstance().getAccessibilityRootNode();
where it calls the following code:
public AccessibilityNodeInfo getAccessibilityRootNode() throws UiAutomator2Exception {
Object queryController = invoke(method(UiDevice.class, "getQueryController"), Device.getUiDevice());
return (AccessibilityNodeInfo) invoke(method(queryController.getClass(), "getRootNode"), queryController);
}
It's not an Appium issue, but Uiautomator by Google, that Appium is using under the hood.
As you can see from the code, you cannot increase the timeout. I suggest trying to reset device/using other device/emulator.

Answer 2

I have a tricky solution ...
This exception usually happens on start of an activity for the first time. So when I get the exception , I just swallow it , sleep for sometime , and try starting it again .
Usually it works ..