Re: [OSDL][BENCHMARK] Database results 2.4 versus 2.5

Andrew Morton (akpm@digeo.com)
Fri, 17 Jan 2003 13:37:18 -0800


Cliff White <cliffw@osdl.org> wrote:
>
> > So it sounds like DBT2 is stabilised now, and producing repeatable results?
> > That's excellent.
> Thanks. the kit's available off Sourceforge now, and we'll have STP version
> up Mondayish.

OK. My utter database ignorance was an
insurmountable-within-two-hour-attention-span problem when I tried to set up
dbt1.

> > So either the I/O scheduler is doing a better job, or the VM page
> > replacement decisions are agreeable for this load.
>
> Okay. Is there something we could do that would point at one or the other?

Different combinations of working set and physical memory will tell us.

Also, when we have a lot of vmstat/etc traces available we can decide how I/O
bound it is, and whether we need to look at upping the request queue sizes.
Which is something which we can now do, and which could easily make a
difference here.

But we'll have to get you onto at least 2.5.58 for that ;)

> would a smaller memory database (say 2GB instead of 4GB ) really show you
> anything interesting on a 4GB system, since there's so little pressure?

Yes, that would be interesting. We're dealing with single points in
twenty-seven-dimensional space. Tweaking input parameter individually helps
one gain an understanding of what is going on.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/