21.5.5 Tuning the buffer length for user-defined type information

This section explains tuning of the buffer length for user-defined type information (pd_type_def_cache_size operand value).

Organization of this subsection
(1) Tuning method (1)
(2) Tuning method (2)

(1) Tuning method (1)

Information to be referenced
See the following system activity statistical information provided by the statistics analysis utility:
Type definition cache hits count (# OF TYPE-DEF CACHE HIT)
Number of type definition information acquisition requests (# OF TYPE-DEF GET REQ)
Tuning procedure
Obtain the type definition cache hits rate with the following formula, and tune it so that the hits rate becomes 100%:
Type definition cache hits rate (%) =
(type definition cache hits count[Figure] number of type definition information acquisition requests)[Figure] 100
Actions to be taken
Increase the value of the pd_type_def_cache_size operand.

(2) Tuning method (2)

Information to be referenced
See the following system activity statistical information provided by the statistics analysis utility:
  • Total type definitions cache size (TYPE-DEF CACHE TOTAL SIZE)
  • Allocated type definition cache size (TYPE-DEF CACHE ALLOC SIZE)
Tuning procedure
Obtain the type definition cache utilization factor with the following formula, and tune it so that the utilization factor becomes 90% or higher:
Type definition cache utilization factor (%) =
(maximum value of total type definitions cache size[Figure] allocated type definition cache size)[Figure] 100
Actions to be taken
Reduce the value of the pd_type_def_cache_size operand.