Re: 2 2.4 cpus vs. 4 1.4 cpus

From: Svend Jensen <Svend_SPAMKILL_at_OracleCare.Com>
Date: Thu, 12 Dec 2002 20:29:13 +0100
Message-ID: <3DF8E389.5090109@OracleCare.Com>

Allen wrote:
> We're thinking about upgrading our oracle production servers, going with
> RAC. Would you rather 2 servers, each with 2 2.4 ghz cpus, or 2 servers
> each with 4 1.4 ghz cpus? Our oracle license is CPU bound so we're
> thinking it would be better to have 2 faster cpus, but maybe oracle likes
> having 4 somewhat slower ones instead. Any clues?
>
> thx..

As always with Oracle - the answer is; it depends (upon your application) Is it more cpu or more i/o bound.

A simple matrix can resolve this, could be setup like this:

active
sessions | <= 4 | 4-8 | >> 8

i/o bound | 2*2 | 2*4 | 2*4

cpu bound | 2*2 | 2*2 | 2*4

Check your statistics/wait interface 1) v$system_event, 2) v$session_event and 3) v$session_wait and do some heavy tracing level 8 on typical sessions. Read/sort the trace files. Cary Millsap (www.hotsos.com) has developed nice tools - could by of use for You.

1) is tree-mile view (very overall)
2) is feed distance view (closer - at session level)
3) is microscope (like trace files)

Find Your bottleneck and decide for best solution.

Regards

/Svend Received on Thu Dec 12 2002 - 13:29:13 CST