2.4. VSAM performance management
The goal of VSAM performance management is to decrease the values of I/O wait time (Tw(IO)) and I/O service time (Ts(IO)) — that is, the I/O response time (Tr(IO)), for the transactions accessing VSAM data. It can be done by avoiding I/O or doing it faster and playing with I/O priorities. These priorities must be closely linked to your business needs.
In this performance chapter, we use two approaches to help you to improve VSAM performance. First, we discuss all the VSAM external parameters whose values may affect performance. We give recommendations based on experience, on how those parameters should be set. This is known as “rule-of-thumb” (ROT) mode. At each topic end you have a set of recommendations, which ...
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