Re: Index vs. table scans in statspack reports

From: Tanel Poder <change_to_my_first_name_at_integrid.info>
Date: Mon, 1 Dec 2003 09:39:09 +0200
Message-ID: <3fcaf01e$1_1@news.estpak.ee>

> "If the hot block is the index root block, a reverse-key index won't
> help. Setting _DB_BLOCK_HASH_BUCKETS to the prime number just larger
> than twice the number of buffers (DB_CACHE_SIZE/DB_BLOCK_SIZE) will
> usually eliminate this problem. Prior to Oracle9i, this parameter had
> a default that caused tremendous contention for this latch; the
> default is correctly set to a prime number in Oracle9i."
>
> I don't like using underscore parameters in a production DB, but if
> Oracle itself endorses it...

I'm quoting Jonathan Lewis from his earlier post in same thread:

"If your version is pre 8.1.7.3, then you may be seeing the root block latch bug - there is a patch."

So, probably you should patch to 8.1.7.4 instead of setting underscore parameters.

Tanel. Received on Mon Dec 01 2003 - 01:39:09 CST