hbase compactSplitThread may lock forever on read datanode blocks.
debug found: epollwait timeout set to 0,so epollwait can not run out.
cause: in hdfs 2.3.0
hbase using DFSClient to read and write blocks.
DFSClient creates one socket using newConnectedPeer(addr), but has no read or write timeout.
in v 2.6.0, newConnectedPeer has added readTimeout to deal with the problem,but did not add writeTimeout. why did not add write Timeout?
I think NioInetPeer need a default socket timeout,so appalications will no need to force adding timeout by themselives.