Re: sched_yield() makes OpenLDAP slow

From: Lincoln Dale
Date: Tue Aug 23 2005 - 22:39:22 EST


Denis Vlasenko wrote:

This is what I would expect if run on an otherwise idle machine.
sched_yield just puts you at the back of the line for runnable
processes, it doesn't magically cause you to go to sleep somehow.


When a kernel build is occurring??? Plus `top` itself.... It damn
well sleep while giving up the CPU. If it doesn't it's broken.


unless you have all of the kernel source in the buffer cache, a concurrent kernel build will spend a fair bit of time in io_wait state ..
as such its perfectly plausible that sched_yield keeps popping back to the top of 'runnable' processes . . .


cheers,

lincoln.
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