Re: db_file_multiblock_read_count and 10g

From: Jared Still <jkstill_at_gmail.com>
Date: Sat, 24 Jan 2009 10:30:40 -0800
Message-ID: <bf46380901241030g40bdf5deqba32475fa24cc774_at_mail.gmail.com>

On Sat, Jan 24, 2009 at 6:44 AM, Á¶µ¿¿í <ukja.dion_at_gmail.com> wrote:

> This is called autotuned MBRC - literally, Oracle autotunes the value of
> MBRC.
>
> This is a good stuffer, but there is something you must be warned before
> you use it.
>
> As of Oracle 10gR2, MBRC is exposed as 2 hidden parameters.
>
>
> - _db_file_exec_read_count : MBRC used by execution engine
> - _db_file_optimizer_read_count : MBRC used by optimizer
>
>
>

Interesting stuff, but I am going to disagree with changing these hidden parameters.

That is because unless you have good reason to change them, what is the reason to do so?

Oracle makes it unnecessary to tweak a parameter, and we replace it with two more.

If your database is performing well, then there isn't much reason to 'tune' it.

Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist

--
http://www.freelists.org/webpage/oracle-l

Received on Sat Jan 24 2009 - 12:30:40 CST