HP-UX 11.00 resources

[Dan SICHITIU]

I have a HP-UX 11.00 cluster (2 x L2000) sharing an AutoRAID, with Oracle Applications 11.0.3 on top on Oracle 8.0.5 RDBMS server (two file systems - ora and app - mounted on either system). There are two database instances running (TEST and PROD).
After a series of patch sets applied on TEST, this database is now used as production and uses a lot of system resources (but what ?) so, when I start PROD (or even if I use fbackup) the concurrent managers run very slowly (there are a lot of "pending" requests) but they are quickly executed as soon as I stop PROD.

Thanks.

[Stefan Farrelly]

Sounds like an I/O bottleneck to me. Seen this before a lot of times - especially on Autoraids. Theyre not very fast disks im afraid (about the slowest HP have made). I would not recomment using one for a production database let alone 2 db's sharing it. You should look into replacing the autoraid with something faster.

[Dan SICHITIU]

But the same AutoRAID were good enough before applying the patch sets on the TEST db.
Note that the AutoRAID has a full set of 10 krpm disks.

[Stefan Farrelly]

What were these patch sets then ? Oracle patches or HP-UX patches ?

[Vincent Farrugia]

Hello,

AutoRAIDs are slow only if you don't setup them well enough. Otherwise, as you say, 10,000rpm disks they are... like all other disks.

The problem with AutoRAID is autoRAID, quite simply :-) What autoRAID does is... it stores the data in all the disks in RAID 0+1 or RAID 5 automatically, according to usage statistics. Thus, if some files are used often, they are stored in RAId 0+1 for fast retreival, whereas if another file is seldom used, it is stored in RAID 5 for compact storing.

Problem is, when it reaches a certain level of storage, autoRAID will keep migrating data back and forth from RAID 0+1 to RAID 5, thus losing performance impressively. This happens when 90% of the autoRAID space is used. How much space are you using? For optimum performance, leave 40% of the space unallocated, for RAID 0+1 usage (which is much faster than RAID 5). To do this, upgrade your disks to larger capacity ones.

HTH,
Vince

[Dan SICHITIU]

Patch sets were applied on TEST, so they are Oracle patches.

[Dan SICHITIU]

AutoRAID has 12 x 18 GB disks (that makes 216 GB) and the two file systems (ora and app) use 50 GB respectively 20 GB, leaving approx. 146 GB unused. I think it is an appropriate situation to reach the AutoRAID best performance.