Re: Do you recommend striping ?

PCS Technologies, Inc. <dadkins_at_pcstech.com> wrote in article <3362B28F.659D_at_pcstech.com>...
> We have been using Oracle for a long time, but have always done explicit
> placement of datafiles across the available disks. Our configuration is
> (we believe) optimal at first, but after a year of production work, we
> get a lot of fragmentation, some extents, etc. We've tried RAID-5, but
> found it too slow.
>
> With AIX 4.2, we have the chance to do disk striping at the Logical
> Volume Manager level, making it very easy. My theory is that over time
> striping will average out the accesses across the disks.
>
> What are your opinions? Does everyone stripe?
> TIA
>

We are currently using AIX 4.0 on a 8 node SP/2. Each note has eight logical disks and we are stripping across all the drives on each node using VSDs and then stripping across each note. So on a table of a few mega bytes or more, all 64 drives will contain some part of a table. When doing full table scans using parallel hint of 1,8 we have found fantastic results. We also are striping our indexes in the same manner and this helped just as much. One note: this is most likely optimal for data warehouses and data marts; Oracles' MPP is great for this stuff!!!

So, Yes, I would recommend stripping, but by a DBA or developer who knows how to strip intelligently.

Good luck. BP Received on Wed Apr 30 1997 - 00:00:00 CDT