HP UX 11.0: Oracle, EMC Metavolumes & Disk Stripping

[LG Porter]

I have a three node cluster composed of three N4000 Class servers running HPUX 11.0 in a MCSG(11.09) configuration connected to EMC 8730 Symmetrix. The servers have been experiencing I/O bottleneck and there is debate going on between the SA and DBA's as to implement stripping. Questions:
1) Is disk stripping offically supported accross EMC Symmetrix disks under HP UX 11.0?
2) If so, to the HP system, if stripping is implemented, would the server see one
physical volume (basically a virtual volume which cotaining all the disks) or
a series of disks?
3) The metavolume for striping has to be created BEFORE it is added to the
system correct? You can't just come back and modify it aftewards right?

[Ross Zubritski]

1. Yes

2. Yes /dev/rdsk/cxtxdx (XXXGB)

3. Correct.

Regards,

RZ

[Ross Zubritski]

It is so funny to see this posted. I ahve almost the identical environment here, and we went through a similar "bavarian arts seminar" with the DBA's a few weeks ago. Just FYI, meta's do show a HUGE increase in performance assuming the code structure of the app is sound. We went from 100 I/Os per sec on SAD (Slow A$$ disk) to a 500 - 800 IO/s range on metas. Pretty dramatic increase.

Regards,

RZ

[John Poff]

Hi,

Just to add to what Ross has mentioned, we done metavolumes on EMC before without striping and the performance increase was exceptional. You might want to consider just trying the metavolumes first without the striping.

JP

[Chris Vail]

We have an 8730, an 8830 and an 8430 with an aggregate of 157TB between 'em. To answer your questions:
1) Yes, striping is supported and works very well. We use 10GB (unstriped), 44 and 88GB striped metas.
2) Yes, the servers see a single volume. Its completely transparent to the O/S.
3) Yes. Although you can fudge it a bit. Take the databases down, and mount both the striped and unstriped disk sets. Then copy the unstriped to the striped using tar or cpio. Then swap the mount points.

Your speed increase will be dramatic. However, let me recommend Power Path instead of PV Links. PV links is great for failover, but PowerPath increases speed as well.


Chris

[Ross Zubritski]

Power Path Rocks!