On Tue, May 18, 2010 at 6:29 PM, Mark Post <[email protected]> wrote: > Looking at column one, you had a maximum of one process waiting to run. It > could very well have been that the system was voluntarily giving up its time > slice. The sudden jump in context switches and interrupts, combined with > that one process being in uninterruptable sleep (column two) when the steal > time goes high suggests that the process was waiting on something.
I think cause and response are the other way around. The "steal" percentage is when Linux had work to do but did not get the cycles. If Linux does not need the cycles, it's idle. When Linux waits for CPU 85% of the time, it only had 15% of the time to do something. So you would expect context switches and interrupts to also drop a lot. The high steal ratio means that Linux did not get the cycles it wanted to have. The z/VM monitor data reveals why that was happening. Without that, we're just guessing. There's many possible reasons for it. Rob -- Rob van der Heij Velocity Software http://www.velocitysoftware.com/
