When we talk about performance issues a couple of things immediately come to mind. Probably first is making sure the expectations are realistic. Then we start the search for the bottleneck. There is always a bottleneck. Sometimes it will be a fast bottleneck but it is still there and you must know where it is before you can do anything else. Once you know where the bottleneck is you will know what your options are to increase performance and you will also have a very good idea what your expectations should really be.
There is not real rocket science involved in locating the bottleneck. It really just involves being systematic, keeping good notes, and having a good plan. There are several places where there is documentation to help with this process including the NetBackup 6.5 Backup Planning and Performance Tuning Guide (updated October 1, 2008) which is available on the Symantec support website...
So you are barely meeting your backup window and now you have decided to replace your old LTO2 drives with faster LTO3 drives, or wait, LTO4 is available. Yeah, let’s go with those. After replacing your 8 old drives with 8 new ones you are ready to relax and watch things run. Why is the phone ringing at 2 AM? Why are backups not finishing within the backup window? Why are things worse? Too many people assume the tape drive is automatically the bottleneck in their backup environment without making sure that is the case. Too many people assume there are only two places to worry about performance, the tape drive and the media server bptm buffers. While these are two places to be concerned about they are not by any way, shape or form the only two places. In fact in today’s backup infrastructure they aren’t necessarily the first place to look. If you will bear with me I would like...
