Re: AIX JFS Striping vs Multiple DB Extents

For a quick answer:

1.  Use TSM mirroring as opposed to AIX LVM mirror.  There have been
many discussions about this, even recently, that this gives you better
protection/recovery capabilties.

2.  Use JFS files and use more disks/spindles.  Ex. for 35GB DB use (4)
9 GB disks as opposed to (1) 36GB disk.  Better performance.  Also have
multiple dbvols from TSM point.  (With 4 disks, then for instance have
(2) 4 GB dbvols on each disk , or maybe (4) 2GB).

3.  Not as familiar with striping performance from TSM point.  I think
some people use it successfuly.  I think depends on how many disks
you have as to whether it works better.

4.  Real performance will be in your disk pools as that where the real
data transfer happens, depending on how much data and how it comes,
ex. large DB clients or small files.

David Longo

>>> rogerd AT UIC DOT EDU 04/30/02 11:06AM >>>
I'm about to do a disk reorg as a part of installing some new disk
drives, and I'm trying to get the best Database performance. The system
is TSM 4.2.1.09 on AIX 4.3.3.09. The processor is slow, but the new
disks are fast SSA disks.

What are the pros and cons of

Using AIX disk striping

           versus

Having multiple TSM Database extents

...and...

AIX JFS Mirroring

     versus

TSM Database/Log Mirroring

...and...

AIX JFS extents for DB and Log

      versus

Raw extents

Short of conducting some rather painstaking tests using my new disks,
(35gb Database) I really have little informaiton regarding the
performance aspects of these choices.

Roger Deschner      University of Illinois at Chicago     rogerd AT uic DOT edu 
============ "The World's Least Intuitive Operating System" ============
=============== -- from the cover of "Unix for Dummies" ================



"MMS <health-first.org>" made the following
 annotations on 04/30/02 13:41:12
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