Why is NFSv4 so slow?

[Rick C. Petty]

On Mon, Jun 28, 2010 at 10:09:21PM -0400, Rick Macklem wrote:
> 
> 
> On Mon, 28 Jun 2010, Rick C. Petty wrote:
> 
> > If it makes any difference, the server's four CPUs are
> >pegged at 100% (running "nice +4" cpu-bound jobs).  But that was the case
> >before I enabled v4 server too.
>
> If it is practical, it would be interesting to see what effect killing
> off the cpu bound jobs has w.r.t. performance.

I sent SIGTSTP to all those processes and brought the CPUs to idle.  The
jittering/stuttering is still present when watching h264 video.  So that
rules out scheduling issues.  I'll be investigating Jeremy's TCP tuning
suggestions next.

-- Rick C. Petty