Why does park/unpark have 60% CPU usage?

Question

Recently we started stress testing our application (an XMPP based chat server) using YJP 11.0.9. During our test we noticed following strange behavior.

1. Sampling sh

Answer 1

With certain low level blocking commands like read/write/park/lock the "CPU" time is over estimated as it assumes it is consuming CPU when actually the operation is blocking. The fact unpark/park are both high does suggest you have a problem, but I suspect you should take the lower of the two percentages as an estimate.