>From experience slow Offsite reclamation from Disk applies to DLT tape also. It applies to all tape, it basically copies files one at a time. See IC15925.
-----Original Message----- From: Mark Stapleton [mailto:stapleto@;BERBEE.COM] Sent: October 31, 2002 5:23 PM To: [EMAIL PROTECTED] Subject: Re: Tape drive recomendations From: ADSM: Dist Stor Manager [mailto:ADSM-L@;VM.MARIST.EDU]On Behalf Of Bill Boyer > Be careful of your copypool reclamations with the disk cache turned on!! > There is a BIG performance hit on reclamation when the primary copy of the > file is on a DISK direct access storage pool. Then the MOVESIZETHRESH and > MOVEBATCHSIZE values are thrown out the window and the files are processed > one at a time. This is true *if* LTO tapes are in the mix. Apparently the aforementioned situation, in conjunction with the LTO backhitch process, makes for *slow* reclamations. > What I've done to relieve the restore times is to not MIGRATE the > disk pools > until the end of the day. That way restoring from last night is > quick. I had > a client where they wanted CACHE=YES on a 60GB disk pool. The offsite > copypool reclamation ran for 2-days! Changed it so that migration > started at 5:00pm and nobody complained about restore times. You can also do a move data on the disk volumes. That will clear the cache on an adhoc basis. -- Mark Stapleton ([EMAIL PROTECTED]) Certified TSM consultant Certified AIX system engineer MCSE
