Re: Database regression due to scheduler changes ?

Brian Twichell
2005-11-07T23:06:15Z

David Lang wrote:

> If I am understanding the data you posted, it looks like you are
> useing sched_yield extensivly in your database.

Yes, I've seen problems in the past with workloads that use sched_yield
heavily.

But bear in mind, the ~2700 sched_yields shown in the schedstats
occurred over a 9 minute period.
That means that sched_yield is being called at a rate of around 5 per
second -- this is not a heavy user of sched_yield.

To put this into a broader perspective, this workload has around 270
tasks, and the context switch rate is around
45,000 per second.