[HDFS-11593] Change SimpleHttpProxyHandler#exceptionCaught log level from info to debug

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.9.0, 3.0.0-alpha4
• Component/s: datanode
• Labels: newbie
• Hadoop Flags: Reviewed
• Assignee: Xiaobing Zhou
• Reporter: Xiaoyu Yao
• Created: 29/Mar/17 21:36
• Updated: 02/May/17 00:06
• Resolved: 01/May/17 23:25

Description

A busy datanode may have many client disconnect exception logged with stack like below, which does not provide much useful information. Propose to reduce the log level from info to debug.

2017-03-29 20:28:55,225 INFO  web.DatanodeHttpServer (SimpleHttpProxyHandler.java:exceptionCaught(147)) - Proxy for / failed. cause: 
java.io.IOException: Connection reset by peer
	at sun.nio.ch.FileDispatcherImpl.read0(Native Method)
	at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39)
	at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223)
	at sun.nio.ch.IOUtil.read(IOUtil.java:192)
	at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:380)
	at io.netty.buffer.UnpooledUnsafeDirectByteBuf.setBytes(UnpooledUnsafeDirectByteBuf.java:446)
	at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:881)
	at io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:225)
	at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:119)
	at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:511)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382)
	at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354)
	at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:116)
	at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
	at java.lang.Thread.run(Thread.java:745)