On Friday 27 February 2009, David Bronder wrote: > Wanda Prather wrote: > > And there is NO instrumentation in Windows to give you any idea whatever > > about what is going on performance-wise on a bus with tape drives > > attached. > > Unfortunately, there doesn't seem to be any real instrumentation in AIX > about tape drive performance, either. None of the standard AIX tools > seem to give tape-related information (e.g. iostat or nmon), either for > the tape drives themselves or for the buses or adapters the drives are > connected to (unless there is also disk behind those buses or adapters). > (Speaking only of FC drives, since the last time I used SCSI tape drives > years ago, I never tried to get that data.) > > So far, neither IBMers nor business partners I've talked to have been > able to identify a way of collecting that kind of data, either. The best > ideas I've been able to come up with are manual timing tests (measure the > time to transfer a known volume of data, whether within TSM or externally) > or to look at stats on the fibre ports on the SAN switches (assuming one > has that kind of access to the switches). > > If anyone can tell me differently, I'd love to hear about it. Even if > (especially if?) it's something dead simple or obvious that I've been > missing. The problem is that the numbers are not available. Don't ask me why.
What I do is starting nmon. With 'a' you can see the adapter stats. With 'V' you van see the volume group stats. The difference is tape drive I/O. Stef