Re: Database Buffer Cache Hit Ratio

pcambraf wrote:
> I didnt like your off topic answers... if you dont want to help me just
> dont say nothing, i wasnt answering for been replyed like that...
>
> Im a DBA jr, in the applications side, cause the real DBAS wont fix
> anything, i just dont have access to sys or system or whatever could be
> called superuser, so i begin with handicap.
> Anyway, im on a OLTP enviroment, with dictionary managment tablespaces,
> its a small system, about 3 o 4 gigs on disk and there are user
> complains, so much. The application is not well written, but fix this
> is not possible, they dont want to (another handicap), ive seen this db
> cache hit ratio so low, and i thought its a problem, and my question
> was: Could a contention in DBWR process (theres only one as ive said
> above) produce a low hit ratio in the instance?

Well, if you don't have access to sys or system (and aren't even sure what the 'superuser' is) then you're not a DBA, regardless of what your business card says.

A low BCHR is a symptom, not a problem. And often, not even a very telling symptom. You may have a problem, and the BCHR may (or may not) be hinting at what that problem is. But chasing the BCHR is not going to solve your problem.

Can you get a statspack report on the database? If so, get it, then feed it into the report analysis at oraperf.com. It will produce a most revealing prioritization of where your problems lie. If it says you will get a 90% increase in performance by solving problem "A", then you are wasting your time looking at anything other than problem "A".

It sounds like your real problem is political, not technical. Why won't the DBAs do anything? Since you have neither real DBA authority nor authority to change the app, why has this become your problem? Received on Thu Oct 06 2005 - 08:21:51 CDT