ADSM-L

Re: [ADSM-L] Disk Storage pool filling faster than it is emptying. ideas?

2010-02-25 02:27:21
Subject: Re: [ADSM-L] Disk Storage pool filling faster than it is emptying. ideas?
From: Hana Darzi <hanad AT EXCHANGE.BGU.AC DOT IL>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Thu, 25 Feb 2010 09:26:38 +0200
What version of tsm server you have?
In tsm 6 there is a bug with the cash . see this:

http://www-01.ibm.com/support/docview.wss?uid=swg1IC66262

Hana

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
km
Sent: Wednesday, February 24, 2010 3:56 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] Disk Storage pool filling faster than it is emptying. 
ideas?

Since you have caching turned off now and have emptied the diskpool (?)
fragmentation should not be an issue.

What is the performance when using only a single LTO4 drive, 1/4 of
30mb/s or 30mb/s?

Check the read performance of the disk with dd or something similar.

What speed do other tape operations get, ie reclamation, backup stg,
dbbackup?

Have you checked errpt for scsi/tape/disk errors?

What kind of HBA is it, 1/2/4/8Gbps? NPIV or native?

How about moving data from tape up to disk, test if that will be limited
to 30mb/s as well.

On 24/02, Dury, John C. wrote:
> We have a 3 TB disk storage pool that until recently, has been filling up 
> partially during backups, and then emptying as the data is migrated to tape. 
> The storage pool is now at 84% and climbing. I have 4 LTO4 Ultrium drives 
> that can't seem to migrate the data fast enough at all. Watching nmon, I am 
> only getting around 30MB/s total when all four drives are in use. They are 
> all assigned to ne HBA because of a lack of slots in the AIX server. I 
> previously had cache turned on for the disk storage pool (it is now off), so 
> I am wondering if the terrible performance is because the disk storage pool 
> is extremely fragmented because cache was turned on for so long. Any ideas 
> how to offload the data to tape faster?
> John