Re: HyperThreading and Arriba?

On Thu, 2004-01-08 at 12:02, Theo Schlossnagle wrote:
> The Arriba is calculated only once.  If you enable hyperthreading, you 
> should delete the "arriba" file that holds that number for it to be 
> recalculated ont hat box.
> 

Actually on these boxes, HT was never turned off. But then I realized
that I had copied the Arriba from an identical machine that did have HT
turned off. So I rm'd the Arriba, stopped apache, counted to 10, started
apache.. and it came out significantly lower all three times I tried it.
The identical non-HT box got 2587086, while the HT box scored 2345555,
then 2329478, then 2416500. AFAIK the box was completely idle for all of
these calculations. Maybe the Arriba calc does something that isn't HT
friendly?

> > 3) Should we experiment with byCPU or byBusyChildren? I tend to think
> > byLoad makes the most sense, since these boxes run some database things
> > that might not register as well with BusyChildren.
> 
> use byBusyChildren
> 

Any reason you suggest this one over byLoad? Or did you mean, just
experiment with it? One thing I don't like about this is that I have to
remember to always 'apachectl graceful' after a stop/start of apache, or
the stats won't show properly.