We have a RedHat server whose only job is to run a JBoss server. Monitors said that memory usage spiked (we have the JVM limited to far less than the total memory on the system) and JBoss crashed. We restarted and everything seems ok now.
Odd thing is that sar data for 10 min leading up to the crash is simply not there. Load average got up to the 50s. I have seen severely busy systems (350+ Load Average) still collect sar data. Does anyone have any idea what could cause sar to stop collecting data?