How to turn off Datacom SQL Source Cache

Products

• Datacom
• DATACOM - AD

Issue/Introduction

Question:

How to turn off Datacom SQL Source Cache.

For example, Datacom Version 15.0 SQL apar TR90499 circumvention says:

  "...

  2. Turn the Source Cache off by setting either limit to zero:            

  SQL_SOURCE_CACHE_SIZE      0                                             

  SQL_SOURCE_CACHE_STMTS   0  

  ..."

The Datacom Multi-User (MUF) does not specify either of these startup options.                                        

 

Resolution

The size of the Source Cache is controlled by the two following MUF parameters and their defaults:

SQL_SOURCE_CACHE_STMTS nnnnnn  (0 – 100,000)      <--- default  1,000

SQL_SOURCE_CACHE_SIZE    nnnnnn  (0- 100M)            <--- default    10M

A value of zero (0) for SQL_SOURCE_CACHE_STMTS or SQL_SOURCE_CACHE_SIZE indicates the SQL Source Cache is not used.

These limits can be dynamically set to zero (0) without forcing a recycle of the Datacom MUF using console command or batch DBUTLTY.

Console commands to the MUF:

/f mufstc,COMM SQL_SOURCE_CACHE_STMTS 0   

/f mufstc,COMM SQL_SOURCE_CACHE_SIZE 0

  

DBUTLTY console command to the MUF:

//SYSIN   DD *

COMM OPTION=CONSOLE,OPTION2='SQL_SOURCE_CACHE_STMTS 0'

COMM OPTION=CONSOLE,OPTION2='SQL_SOURCE_CACHE_SIZE 0' 

/*                                                    

 

Additional information:

See the Datacom Core - 15.1 documentation section - SQL Source Cache.