Greg Ames wrote: >>On Wed, Jan 09, 2002 at 11:55:21PM -0800, Brian Pane wrote: >> >>>My hypothesis upon seeing these numbers is that the high run queue length >>>is due to us hitting some bottleneck in the kernel on daedalus--and because >>>post-2.0.28 releases waste less time in usr-space code between syscalls, >>>they hit that kernel bottleneck a lot harder than 2.0.28 did. >>> > >An interesting theory. But it doesn't explain the high numbers of CPU ticks >I've recorded for trivial requests, nor does it explain the top Brian B sent us >with two httpd's both using over 50% of the CPU for a while >
It might explain the high number of CPU ticks for simple requests if a lot of processes are hitting, say, a spin lock at the same time. But the two httpds using 50% of the CPU are definitely something different. We really need some data on what's happening in those processes on daedalus. --Brian
