Re: Question on Collocation with 7337 library
You can do this but ... Having all users collocation isn't going to happen very fast. In fact it may never happen. Correct me if I'm wrong but in the past collocation was described to me as: "put every user on his own tape until you run out of tapes (maxscr=) then start 'doublling' up the users to tapes that have the most room." Now Consider the situation: You have 10 tapes with 40+/- users. Each tape is now "FULL" and the composition of the "FULLNESS" is: "whatever users did backups while that tape was "Filling"" As these non-Collocated tapes become reclamated all users on them will be written to any scratch tapes up to the maxscr parm. With a 7337 you may have one to three scratches available. The transfer of all users to new tapes may end up with most (if not all) those users going to the same one to three tapes. SO now you have 40 users coming off one tape and going to 2 (40/2) or 3 (40/3) Not much of a collocation. Do you make offsite copies? Those tapes will take up a tape slot or two as well. Another topic: DLT's. I found with collocation ON using a 7337 that the DLT's got beat-to-hell with a lot of mounting and finding the last record and writing more on it , etc, etc. Within 10 months I had tape drive and dlt failures from the intensive use of them for the sake of collocation. Hope these thoughts help. Joseph A Faracchio, Systems Programmer, UC Berkeley On Fri, 12 Jan 2001, Eric Tang wrote: > Hi All, > > Environment: > - TSM v3.7.3 > - IBM7337 library (15 slots) with around 10 tapes for onsite tape pool > status full, a cleaning tape and 3 to 4 scratch tapes > - Currently there are around 40 nodes defined in TSM > - a few more nodes are coming and backup data volume on existing nodes is > expected to grow, so there will be move media operation soon > - there is only one onsite tape storage pool defined and that is having > collocation off > > To improve restore performance, I am thinking of turning on collocation for > onsite tape pool. But there are more nodes than number > of slot in library, should I define maxscratch=N and let TSM to collocate > data on the 40 nodes within the N tapes. Keep monitoring tape usage and > adjust N whenever necessary. Any suggestion on the setup and the number N? > > Thanks in advance. > > > Regards, > Eric Tang >
Re: Question on Collocation with 7337 library
Yes, that's the way to do it. I would also define another non-collocated tape storage pool and point the original pool at that one and set the migration threshold to 98%. That way, if your first pool gets close to filling, TSM will consume a scratch tape in the new pool and keep on going avoiding the dreaded server out of data storage space. When you detect that this has happened you can simply issue a move data on the volume in the second pool: move data secondpoolvolume stg=firstpool, to get it back in the correct pool. Set N to the maximum number of tapes you want consumed by this pool in the library. Then, contemplate getting a bigger library! ;') Kelly J. Lipp Storage Solutions Specialists, Inc. PO Box 51313 Colorado Springs CO 80949-1313 (719) 531-5926 Fax: (240) 539-7175 Email: [EMAIL PROTECTED] or [EMAIL PROTECTED] www.storsol.com www.storserver.com -Original Message- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED]]On Behalf Of Eric Tang Sent: Friday, January 12, 2001 7:58 AM To: [EMAIL PROTECTED] Subject: Question on Collocation with 7337 library Hi All, Environment: - TSM v3.7.3 - IBM7337 library (15 slots) with around 10 tapes for onsite tape pool status full, a cleaning tape and 3 to 4 scratch tapes - Currently there are around 40 nodes defined in TSM - a few more nodes are coming and backup data volume on existing nodes is expected to grow, so there will be move media operation soon - there is only one onsite tape storage pool defined and that is having collocation off To improve restore performance, I am thinking of turning on collocation for onsite tape pool. But there are more nodes than number of slot in library, should I define maxscratch=N and let TSM to collocate data on the 40 nodes within the N tapes. Keep monitoring tape usage and adjust N whenever necessary. Any suggestion on the setup and the number N? Thanks in advance. Regards, Eric Tang
Question on Collocation with 7337 library
Hi All, Environment: - TSM v3.7.3 - IBM7337 library (15 slots) with around 10 tapes for onsite tape pool status full, a cleaning tape and 3 to 4 scratch tapes - Currently there are around 40 nodes defined in TSM - a few more nodes are coming and backup data volume on existing nodes is expected to grow, so there will be move media operation soon - there is only one onsite tape storage pool defined and that is having collocation off To improve restore performance, I am thinking of turning on collocation for onsite tape pool. But there are more nodes than number of slot in library, should I define maxscratch=N and let TSM to collocate data on the 40 nodes within the N tapes. Keep monitoring tape usage and adjust N whenever necessary. Any suggestion on the setup and the number N? Thanks in advance. Regards, Eric Tang
Question on Collocation with 7337 library
Hi All, Environment: - TSM v3.7.3 - IBM7337 library (15 slots) with around 10 tapes for onsite tape pool status full, a cleaning tape and 3 to 4 scratch tapes - Currently there are around 40 nodes defined in TSM - a few more nodes are coming and backup data volume on existing nodes is expected to grow, so there will be move media operation soon - there is only one onsite tape storage pool defined and that is having collocation off To improve restore performance, I am thinking of turning on collocation for onsite tape pool. But there are more nodes than number of slot in library, should I define maxscratch=N and let TSM to collocate data on the 40 nodes within the N tapes. Keep monitoring tape usage and adjust N whenever necessary. Any suggestion on the setup and the number N? Thanks in advance. Regards, Eric Tang
