Re: performance improvements from putting tables and indexes on seperate disks?

From: Greg Rahn <greg_at_structureddata.org>
Date: Fri, 8 Feb 2008 21:52:38 -0800
Message-ID: <a9c093440802082152y52ed72e7t5df4ce4bd0183fb1@mail.gmail.com>


If it were an option, I would load into a staging table, build indexes, and partition exchange. This yields the best of all worlds: parallel direct load with no index maintenance, parallel nologging index builds, and doesn't effect queries.

My recommendation: Leverage ASM and not worry about it. You will get the best performance with the least effort.

On 2/8/08, ryan_gaffuri_at_comcast.net <ryan_gaffuri_at_comcast.net> wrote:
> Are there any benchmarks testing whether there are performance improvements on reads and writes when you separate data and indexes on separate disks?
>
> cases:
>
> 1. sqlloader direct path load of a large number of records to a table with 4-5 indexes. The indexes can't be dropped during loads since queries take place during the load.
>
> My understanding is that the write process is serial so separating the data and indexes onto separate disks will not improve performance much. I don't have the disks to test this on right now.
>
> 2. queries. mainly oltp type queries. any performance improvements for separating the hard disks that tables and indexes are on?
>
> This is on a SAN, but we can have it configured to give us separate disks and show them to us as separate mount points.

-- 
Regards,

Greg Rahn
http://structureddata.org
--
http://www.freelists.org/webpage/oracle-l
Received on Fri Feb 08 2008 - 23:52:38 CST

Original text of this message