RE: pumping storage using DST

[Jim Damato <jdamato@xxxxxxxxxxxxxxxxx>]

In theory STRASPBAL can be run while the system is up.  We've found that in
practice it's brutal.  While it's running against our production ASP
interactive and batch jobs are prohibitively slow.  It's probably because
our disk is overutilized -- we have always had too few spindles for our
system.

I'll rethink the schedule.  We had considered running on both old and new
towers for a week, installing disk and removing disk on separate weekends.
We had decided to "bite the bullet" and only screw up one weekend, but it's
leading to discussions about things like whether we really need to perform
RCLSTG.  Still, STRASPBAL can't really be run with production jobs.  We may,
however, be able to steal time here and there to get the first 50% of the
disk migrated without shutting down the system.  I guess the benefit of
STRASPBAL is that it can be started and stopped, where DST requires
dedicated time until selected disk units are removed.

Thanks for everyone's advice.

-Jim

-----Original Message-----
From: Andy Nolen-Parkhouse [mailto:aparkhouse@attbi.com]
Sent: Wednesday, July 24, 2002 11:26 AM
To: midrange-l@midrange.com
Subject: RE: pumping storage using DST


Jim,

If you were able to postpone the removal of your 8 GB drives, it would
move the data while your machine was in production, so speed would not
necessarily be a factor.  Since you are adding higher capacity drives,
the STRASPBAL command would probably move more than 50% of the data
because it will try to get all drives to an equal percent utilization.

This would only be a viable option if you could add the drives on one
weekend and remove them the next.  The amount of data to pump would be
considerably less.

Regards,
Andy Nolen-Parkhouse