IBM eServer zSeries 990 (z990) Cryptography Implementation

Chapter 6. Performance and monitoring 197

However, it is important to remember that these records are only periodic and not

necessarily regular, so the records do not provide an accurate time series, and

are only representative of the overall activity. They may be useful when trying to

track delays, but this is not guaranteed.

Also, note that there are different function codes recorded in these records, each

with different characteristics. As can seen from the graph, some of them have

much longer elapsed times than others, in normal operation, so you need to

ensure you are comparing the response times of the same functions. The

amounts of data being processed per operation will also affect the elapsed times,

but this is not recorded in the ...