Choosing cache types

This cache balances system impact with the probability that the cache is large enough to handle all of the preimages that will be stored in the cache at one time.

System impact usually consists of increased system paging, such as:

• Paging of XBM address space control structures
• Paging of data in the XBM virtual storage caches
• Paging of other address spaces as the result of XBM central storage allocation

To specify an appropriate cache, you must know what resources are available to your system and what kind of activity occurs on the system.

This section contains the following topics:

• Cache size
• Cache types supported by XBM
• Cache type advantages and disadvantages
• Simulate mode and snapshot processing