topic Re: Script to load balance disks in Operating System - Linux

Script to load balance disks

frederick hannah — Thu, 05 Oct 2006 09:29:28 GMT

Is there a script available that will load balance disks? My shop uses an XP array so there are numerous disks under serveral volume groups.

Re: Script to load balance disks

Steven E. Protter — Thu, 05 Oct 2006 09:42:01 GMT

Shalom,

Normally load balancing for disk is done with a hardware configuration, not a software configuation.

All you can really do is make sure that you have your data laid out so there is not too much heavy actvity files on the same luns.

You can improve write performance on the XP array by setting up heavy write environments to raid 1 instead of the default raid 5.

SEP

Re: Script to load balance disks

Michal Toth — Thu, 05 Oct 2006 10:01:20 GMT

unless you run tru64's advfs

Re: Script to load balance disks

Bill Beresnak — Tue, 12 Dec 2006 11:46:13 GMT

I'm looking for the same thing. The problem is balancing primary and alternate links amoung the volume group and controller paths/chips. The alternate link on a dual pathed controller only get's used by default if the primary becomes unavailable. So, theoretically you could have all of your I/O going over one path on one controller.

I think that's what frederick had in mind.

This is the same thing we are struggling with right now. You can change the primary/alternate simply by vgreducing and vgextending vg's.

The trick is to get a script that is smart enough to pick the right PV/link to remove and readd to get everything balanced.