Possible Threading problem with -CURRENT / MySQL?

[Julian Elischer]

On Mon, 14 Jun 2004, JG wrote:

> 
> I just posted this to -AMD64 and someone brought this discussion to my 
> attention...
> anyway I'll repost it here since it seems to be a more relevant discussion:
> 
> 
> I got a couple emails from people telling me I should retest
> because some changes have been committed recently that
> might effect my MySQL benchmarks.
> 
> Well I just did a buildworld and kernel to -CURRENT & it did
> effect the results alright... just not the way we wanted them to:

erk! :-)

As I suggested elsewhere:
----- quoted----

To check this you should try running systat -vmstat
while noticing the slowdown and try see what is at 100%.
if it turns out that you are NOT seeing disk or CPU limitted
then the next step would be to take a snapshot of operations using 
ktrace -d -p (pid)  for 20 second followe by krtace -C to turn it off
again.

then looking at the output may give an idea of what operations are
taking too long, and what is waiting on what..

Julian