For the third version Redbooks update of IBM Spectrum Archive V1.2.2 we added a performance section. Many years ago I had responsibility for a performance department. The team trained me quickly in case I needed to talk to customers. They said all I needed to know was how to say "It depends". We all had a good laugh about my training but there was a lot of truth to the statement. The truth behind the statement was that most environments are unique and there is no one answer to solve every performance issue for seemingly similar environments. You have to dig into the details. I made a visit to a customer during my backup development days to discuss product performance issues. The standard support process including help from the performance team did not resolve the issue so I was asked to visit the customer.
We started the first meeting with the client technical team and management with the support and performance team on the conference phone. The first question was what changed. After getting the answer, "nothing" we talked about the data flow. After about fifteen minutes the "Ah ha!" moment happened when someone from networking remembered they had been doing some switch testing with another location 1,000 miles away and maybe, just maybe, the data from one data center room to another room next to it was taking a 2,000 mile detour. "It depends" became my mantra for many years.
Performance data is critical to help planning, validation of the implementation, and the ongoing success of the solution. As you can see in the figure below the migration performance data between TS1150 and LtO-7 tape drives would be very helpful for planning a Spectrum Archive solution.
For more detailed migration performance information see the IBM developerWorks topic Spectrum Archive EE Migration Performance and the
In addition to the performance section the following topics are new in Redbooks Spectrum Archive Version 1.2.2:
- Added new write failure state, Write Fenced
- Added new pool remove option, -E for removing tapes with no file references
- Increased stability and performance
- Improved export/import
- Improved reconcile
- Automated the recover process of write failure tapes
- Added improved method for recovering read failure tapes