Changing MAXACIDSIZE

Products

• Top Secret

Issue/Introduction

How to change the MAXACIDSIZE (maximum size of an ACID) from 256K (the default) to 1024K?

Environment

Release: 16.0

Resolution

To increase MAXACIDSIZE, the following steps are needed: 

1. Allocate a new VSAM security file using member VSAMDEF3 in the Top Secret CAKOJCL0 library.
2. Allocate a new BDAM security file using members TSSMAIND and TSSMAINS in the Top Secret CAKOJCL0 library.
3. Specify MAXACIDSIZE(1024) (or any value between 256 and 1024) in the CAKOJCL0 SECPARM member before running TSSMAINS.
4. Run TSSXTEND to copy the current backup security files (BDAM and VSAM) to the newly allocated files. Issue a TSS MODIFY(BACKUP) to take an immediate backup, before running TSSXTEND.

The change will be in effect for all ACIDs. Any ACID that reaches 256K in size will be allowed to grow to the MAXACIDSIZE value.

 

Additional Information

• In a multi-CPU/LPAR security file environment, the change can be implemented one security file at a time.
  
  
• The size of the security file does not have to be increased nor is there any impact on performance.
  
  
• The change will not make every ACID automatically grow to that size. Most ACIDs are very small in size. (The size is shown if you do a TSS LIST(acid) DATA(BASIC) for the ACID.) The current ACIDs will stay the same size. The change only allows for ACIDs to grow beyond 256K if the ACID ever reaches that size.