ADSM-L

Re: [ADSM-L] Moving the TSM DB2 database (AIX)

2014-03-26 14:46:26
Subject: Re: [ADSM-L] Moving the TSM DB2 database (AIX)
From: Kevin Kettner <kkettner AT DOIT.WISC DOT EDU>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Wed, 26 Mar 2014 13:44:23 -0500
Thanks, I will investigate that a bit. Sounds plausible.


On 3/26/2014 13:04, Colwell, William F. wrote:
When I had TSM databases on Netapp - both v5 & v6 - I had to do frequent netapp
'reallocate' commands to get the physical order in the netapp to match
the logical order of db2.

The db2 backup is reading the database sequentially, but within the netapp it
is completely out of order.

Try doing ' wafl scan measure_layout' to get a measure of the disorder.

Bill Colwell
Draper Lab

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Kevin Kettner
Sent: Wednesday, March 26, 2014 1:24 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: Moving the TSM DB2 database (AIX)

That is what I'm leaning towards as well. I've got NetApp looking at the
disk end to see if its getting hit hard. I also want to find out if the
work load is heavier on reads or write (I'm guessing read) to know what
sort of hardware fix is best for this, cache, flash, or more spindles, etc.

  From Wanda's email, they're using a DS3512. I wouldn't expect that to
be much different, performance wise, than the NetApp 3160 that I'm
using. That leads me to think that maybe it's not the disk afterall...

On 3/26/2014 11:30, Ehresman,David E. wrote:
Kevin,

My gut reaction is that your disk drives can't feed the data fast enough.  If 
it were me, I would open up a PMR to find out what the real bottleneck is.

David Ehresman
University of Louisville.

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Kevin Kettner
Sent: Wednesday, March 26, 2014 11:34 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] Moving the TSM DB2 database (AIX)

On the original question, I have moved DBs on AIX with LVM several times
with good success. The only real concern is the performance impact. The
benefit over mirroring is you can do it with no outage at all.

I have 3 servers with similar sized DBs on AIX with NetApp SAS disk on
the back end, backing up to IBM 3592 drives, and my DB backups take 4-6
hours. I'm on 6.3.4 now and I've tried using more streams but that has
not made much difference.

My smallest production DB is around 200 GB and it takes about an hour to
backup.

I wonder what's going wrong. Do you have any advice?

Thanks!

On 3/21/2014 15:42, Prather, Wanda wrote:
Was just thinking the same -
It's only the conversion from V5 to V6 that takes forever.  Once you are 
V6/DB2, DB backup-restore is fast again.

I have TSM 6.3.4 on Windows, DB is 930G used, DS3512 disk, and it will back up 
to LTO5 in 90 minutes if the server isn't doing a lot else at the time.  
Restore takes maybe 15 minutes longer.

You've got other issues you should address, if your DB backup is taking many 
hours @ 300GB....

W


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Ehresman,David E.
Sent: Friday, March 21, 2014 9:11 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] Moving the TSM DB2 database (AIX)

I've used migratepv to move oracle DBs around with no problems.  I would not 
expect any issues with using LVM mirroring or migratepv to move the TSM DB.  
That is what I would do in your situation.

But your comments about taking days to backup and restore your TSM DB worries 
me.  How long does it take to backup your DB?  I have a 600G allocated/415G 
used TSM DB.  It backs up in under an hour and restore time is about the same.

David Ehresman
University of Louisville

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Roger Deschner
Sent: Thursday, March 20, 2014 11:35 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Moving the TSM DB2 database (AIX)

Now that TSM V5 is gone from our shop and we're all TSM V6.2, it's time to move 
some things around. Such as the TSM DB2 database. The manual says to do a full 
database backup and restore. That could take days of downtime with our 
150-300GB databases, and a lot of angst, so that is not really acceptable.

What I'm planning to do instead, is what I've always done on AIX. It's one of 
the reasons I like AIX for hosting something like TSM. That is, to basically 
walk the database over to the new location using AIX LVM mirroring. All this 
with TSM up and running, albeit with a performance impact. (It's Spring Break, 
so the performance impact is acceptable.) The end result will be that the 
database has exactly the same Unix filesystem names, path names, and file names 
as before, except that it will be on a nice new faster disk subsystem.

Other than the obvious performance impact while AIX LVM is doing the mirroring, 
is there anything wrong with moving a TSM DB2 database by this method? Anybody 
done this and had problems?

Roger Deschner      University of Illinois at Chicago     rogerd AT uic DOT edu
======I have not lost my mind -- it is backed up on tape somewhere.=====