Yes! An old APAR cover's this issue, see below. When you are running offsite reclamation watch the throughput when it is reading from disk as opposed to reading from tape. It just crawls.
Apar IC15925: -------------------------------------------------------------------- ERROR DESCRIPTION During an offsite reclamation process; where files are being transfered from disk to tape. ADSM fails to group the files together into transaction groups. Instead the files are processed sequentially. Hence a file will be reclaimed and committed before the next file will be process. ADSM needs to honor the movebatchsize and movesizethresh options in the server options file, so that the files will be grouped together properly for reclimation. As a note, this problem will only be seen where off-site reclamation is occuring from disk to tape. COMMENTS: After taking a very close look at the solution for this APAR, it was determined that the code needed for this performance enhancement is significant because it requires a restructure in the offsite reclamation transaction processing. A requirement can be taken to include this performance improvement in the next release or version. -------------------------------------------------------------------- Tim Rushforth City of Winnipeg -----Original Message----- From: Steve Schaub [mailto:Steve.Schaub@;HAWORTH.COM] Sent: October 31, 2002 11:15 AM To: [EMAIL PROTECTED] Subject: Re: Tape drive recomendations If I'm reading this correctly, only migrating my diskpool down to 10% is hurting my DRM reclamation? Are you saying that putting in a 10TB diskpool that never goes to primary tape (only dr copies) would give me monstrously bad reclamations? Our current main diskpool is 100gb on SSA and has caching on. I haven't had a terrible problem with DR reclamation, though the storage pool backup to DRM only has a throughput of about 5mb/sec. -----Original Message----- From: [EMAIL PROTECTED] Sent: Thursday, October 31, 2002 11:03 AM To: CITY.WINNIPEG.MB.CA.TRushfor; VM.MARIST.EDU;.ADSM-L Subject: Re: Tape drive recomendations And the issue is still there if you don't use CACHE=YES but don't completely clear your backup pool. We have more disk in our storagepool than is required for one night's incremental - so we thought keeping some backups on disk was a good thing (why migrate to tape if you don't need the space). Tim Rushforth City of Winnipeg -----Original Message----- From: Bill Boyer [mailto:bill.boyer@;VERIZON.NET] Sent: October 31, 2002 9:01 AM To: [EMAIL PROTECTED] Subject: Re: Tape drive recomendations 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. 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. Bill Boyer DSS, Inc.
