Re: VMS CPU Bound in performance testing

Jeff,

We had a similar experience on our Alpha 2100 (dual processors, OpenVMS 6.1, Oracle 7.1.5.2.3). The problem turned out to be a missing index that caused extensive looping. All of the data fit in memory, so no IO was incurred after the data was loaded into the SGA. The machine went 100% computable on one processor (only one bad job running) for 30 minutes while we researched it. We discovered the missing index by checking out the V$SQLAREA statements and performing explain plans using the second CPU. R*Tech's SQLab product did most of the grunt work.

There are a dozen possibilities. Can you supply more details?

Matt...

In article <315C06D5.2016_at_marvin.com>, Jeff Johnson <jeffj_at_marvin.com> wrote:

> Jeff Johnson wrote:
> >
> > In initial performance testing of a new Order Management System on an
 DEC Alpha 2100(dual 190 mhz) with OpenVMS version
> > 6.1 with 1G of RAM and Oracle 7.1 we ran into the major constraint of
 CPU utilization going to 200%. This seems strange
> > that a database would be CPU constrained not IO bound. Any ideas
 would be appreciated. Is it SMP memory allocation?
> > other??.
> >
> > Thanks in advance,
> >
> > JeffJ_at_marvin.com
>
> Perhaps I should read my messages before I post them. Instead of SMP I
 meant to say SGA. The system had a shared pool
> size of 50M. Can too small of SGA cause the CPU to work over hard??
>
> Other things of note are the application was written in Forms 3.0.
>
> Thanks again;
>
> jeffj_at_marvin.com
Received on Fri Mar 29 1996 - 00:00:00 CET