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Date: Sat, 8 Jan 2005 21:38:31 +0000 (GMT)
From: Robert Watson <rwatson@freebsd.org>
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Subject: Re: Benchmark: NetBSD 2.0 beats FreeBSD 5.3
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On Sat, 8 Jan 2005, Charles Sprickman wrote:

> Any idea what type of impact this patch would have on say, a large qmail
> server that's drowning in context-switches? 

Probably not, but if you have a tolerance for doing profiling, loading
debugging code, etc, there may be other things we can do that will help.
Are you interested in spending a bit of time profiling the system to see
what's going on?  In particular, is the system actually live locking, or
just getting very bogged down and as a result performing badly?

A few things that would be quite interesting to see up front:

- dmesg
- A couple of screens of output of "systat -vmstat 1", perhaps over the
  course of 5 minutes.
- A couple of screens of output of "top -S", also over the course of 5
  minutes.

Of particular interest would be how much time is being spent in system vs
user or idle cpu, and whether this is an SMP box or not.  Is the box
running with the MPSAFE network stack?

Robert N M Watson