Re: 2.4.8-pre1 and dbench -20% throughput

[Marcelo Tosatti]

On Sat, 28 Jul 2001, Daniel Phillips wrote:

> On Saturday 28 July 2001 02:35, Steven Cole wrote:
> > I also saw a significant drop in dbench 32 results.
> > Here are a few more data points, this time comparing 2.4.8-pre1 with
> > 2.4.7.
> >
> > 2.4.7   9.3422 MB/sec vs 2.4.8-pre1   6.88884 MB/sec average of 3
> > runs
> >
> > The system under test has 384 MB of memory, and did not go
> > into swap during the test.  I performed a set of three runs
> > immediately after a boot, and with no pauses in between individual
> > runs.  I used time ./dbench 32 and caputured the output in a file
> > using script `uname -r`.  The tests were done with X and KDE running,
> > but no other activity.
> 
> The variation is accounted for almost entirely by the change in system 
> time.  Does this mean more IO's or more scanning?  I don't know, more 
> research needed.
> 
> We need Marcelo's vm statistics patch, I wonder what the status of that 
> is.

Well, I've switched to Andrew Morton's generic stats scheme. 

I've also started writing a new userlevel tool (based on cpustat.c from
Zach Brown) to "replace" the old vmstat.c.

Right now I'm busy fixing clients problems and kernel RPM bugs, but I hope
to have the new vm stats patch using Andrew's scheme plus the userlevel
tool until the end of the week.