Purpose

The pmemcachesize attribute defines a hard limit for space usage in the persistent memory (PMEM) cache. The limit cannot be exceeded, even if the cache is not full.

Syntax

 ALTER IORMPLAN 
   dbplan=(( name=db_name, ... pmemcachesize=number ... ) ... )

Usage Notes

• You specify the value for pmemcachesize in bytes. You can also use the suffixes M (megabytes), G (gigabytes), or T (terabytes) to specify larger values. For example, 300M, 150G, or 1T.

• The value for pmemcachesize must be at least 4 MB.

• The pmemcachelimit and pmemcachesize attributes cannot be specified in the same directive.

• The value for pmemcachesize cannot be smaller than pmemcachemin, if it is specified.

• In an IORM plan, if the size of the PMEM cache can accommodate all of the pmemcachemin and pmemcachesize allocations, then each pmemcachesize definition represents a guaranteed space allocation.

  However, you can use the pmemcachesize attribute to over-provision space in the PMEM cache. Consequently, if the PMEM cache size cannot accommodate all of the pmemcachemin and pmemcachesize allocations, then only pmemcachemin is guaranteed.