I was wondering if there is a way to measure the disk IO latency at ZK
server for reads/writes performed to the transaction log and snapshots. In
is experiencing higher transaction latencies it would be useful to
verify whether it is due to disk or network.
We need to add this for debugging our application since we do not have
ZK logs on dedicated disks. If the disk IO is not currently monitored, I
was thinking of extending the streams used in FiLeSnap.java and
FileTxnLog.java, and measure the time taken to do the IO.
Does this sound like a good place to measure the latency?
Will it useful to have this in the tree?