Re: performance drop of >35% from Oracle 7.1 to 8.05

I didn't really notice this performance drop, but then I have a small number of concurrent users and I made several other configuration changes at the time of the upgrade (much bigger SGA using reserved memory, different distribution of data files, redo logs on disk drives).

Gord.

Dirk Munk <d.munk_at_kpn.com> wrote in message news:01bfcf04$73b73ab0$ab4815ac_at_HKTGN0002251944...
> After an upgrade from VMS 6.2 & Oracle 7.1 to VMS 7.2 & Oracle 8.0.5 we
> noticed a performance drop of > 35 %.
>
> At the same time the buffered IO rate went sky high and CPU utilization
> went up too.
>
> After close examination we found that in the old situation a given program
> with SQL statements consisted out of one process that communicated with
 the
> database listner.
>
> In the new situation the program is made up out of two processes, one
> process with the same name as the old process, and a second Oracle process
> that communicates with the database listener.
>
> The communication between both processes is done by means of mailboxes,
 and
> that explains the terrible loss in performance and the high buffered IO
> rate & CPU utilization.
>
> A mailbox in VMS is a device like any other device, and writing to and
 from
> a mailbox is normal IO with all overhead attached to it.
>
> Has anyone experienced this problem before (seems Oracle 7.3.4 already had
> this problem), and did anyone find a workaround ?
>
> Regards,
>
> Dirk Munk
> KPN Telecom
>
>
>
Received on Mon Jun 05 2000 - 00:00:00 CDT