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.=====
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