Joni, If you read Ben Bullock's recent posting, I agree with everything he has said. I would definitely use raw disk volumes (in a Unix world).
Leigh -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Joni Moyer Sent: 17 August 2005 20:31 To: ADSM-L@VM.MARIST.EDU Subject: Re: [ADSM-L] AW: [ADSM-L] Migration Speed Has Plummeted Hi Leigh, I have just added EMC fibre channel disk from a CX700 in the following pieces of physical disk under the filesystem /tsmdev/stgpool1 CHRS044 /tsmdev/stgpool1 lun 175 100 GB lun 178 100 GB lun 181 100 GB lun 184 100 GB lun 187 100 GB lun 190 100 GB lun 193 100 GB lun 199 100 GB lun 204 100 GB lun 210 100 GB Total 1000 GB When you stated using many small TSM disk storage pool volumes, would anyone happen to know what a good, acceptable size TSM volume would be? Thanks! ******************************** Joni Moyer Highmark Storage Systems Work:(717)302-6603 Fax:(717)302-5974 [EMAIL PROTECTED] ******************************** "Leigh Reed" <[EMAIL PROTECTED] > To Sent by: "ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager" <[EMAIL PROTECTED] Subject .EDU> Re: AW: [ADSM-L] Migration Speed Has Plummeted 08/17/2005 10:39 AM Please respond to "ADSM: Dist Stor Manager" <[EMAIL PROTECTED] .EDU> Joni The following URL is to the TSM V5.3 Technical Guide Redbook. If you go to section 3.4.6, it discusses some changes in TSM 5.3 that lend themselves to 'disk only backups' Obviously, if you're not at 5.3 yet, then they may not be of use to you. I personally would consider SATA disk as a possible replacement to sequential tape, but I would still use good quality fast disk as traditional 'random' disk pool to stage the nightly backups. I think that it is widely recognised that significantly 'slicing up' the diskpool into a large number of smallish volumes, greatly improves performance (certainly on the backup). I believe that this is because of the 'multi-threaded' nature of TSM. I would imagine that the config for the best performance of SATA disk as random TSM backuppool, would be to configure each SATA disk as a single TSM volume within the backuppool and ensure that you have enough SATA disks/backuppool volumes as you have sessions in at the same time. However, with SATA disk capacity increasing rapidly, it's not efficient to have a 100 x 250GB SATA disks (100 TSM volumes) sitting in your backuppool, that only ever get 10% utilised. I must state that this is just my opinion, I have no direct experience with SATA disks. Leigh
