I have a Quantum DXi disk storage unit, and I have a Quantum Scalar i500 tape library. Starting just a few weeks ago, and it seemed sudden, our jobs started running late into Monday morning. I opened a case with support, but I haven't made any real progress in over a week. What is going on is that backups are running, but then duplications are kicking off during them--so the rehydration of data and writing it to tape, and actual first-write jobs, are competing with each other. Obviously this is going to cause contention; but for some reason just starting a couple weeks ago this has come to a head, and now I'm trying to correct this.
Currently the answer was to take SLP jobs and turn them off until Monday morning, which I don't agree with; because then tape duplications are running way into Wednesday. (I usually use Tuesday daytime for my maintenance window, since there aren't normally a lot of backups running.)
There are several settings I have been looking at:
Storage -> Storage Unit Group -> Storage Unit -> Max Concurrent Jobs (30 each, there are 2)
Devices -> Disk Pools -> Disk Pool -> Limit I/O Streams (60)
I'm not looking for someone to tell me a best practice--I know I need to do tuning, and I have the white paper on my disk unit.
What I am trying to wrap my head around is what exactly each of these does. From what I have read, the max concurrent jobs is only for *jobs writing to the storage unit*, not for other things like duplications, etc.
If someone could point out where that is mentioned to me in one of the user guides, I would be very happy.
I've already done some research...
https://www.veritas.com/community/forums/large-amo...
https://www.veritas.com/community/forums/best-prac...
https://www.veritas.com/community/forums/maximum-i...
The other settings I have been looking at have been in the master server's SLP parameters; namely, the force interval for small job and job submission interval. Currently these are set for 9 hours. This to me means that after a backup completes the SLP copy of it won't kick off for at least 9 hours. That apparently was working in the past, up until this point; and I'm wondering if the solution might be as simple as making it 10 or 11 (or, is the problem the other way around, that I have it set too long?)