Question:
Our health check reports IDMS_CHANGE_TRACKING not activated and we are looking into activating it.
We shutdown our CV once a week and our intention would be to reformat the SYSTRK* files after every successful shutdown so we would avoid running into space issues on the SYSTRK* files. Is this a good way to go? Or is there already an internal mechanism at CV startup that takes care of the SYSTRK* files?
Answer:
The size of the SYSTRK files is primarily determined by the size of the DMCL. In other words the number of areas and files defined within the DMCL. Sizing considerations are described in the CA IDMS Utilities Guide under the FORMAT statement.
The file does not accumulate images of all CV executions since the creation of the file. It works much like a PDS in that it keeps the previous image and builds an image for the new CV execution. The 'old' image is then reused during a future execution. Starting to vary areas using a permanent option can increase the size requirement but it should not be too significant of an increase. If you alter the size of the DMCL then you will have to perform the sizing steps described in the CA IDMS System Operations Guide.
Reformatting the file continually would result in you losing any permanent area status values set during a previous execution of the CV although it would still provide the recovery aspects of the SYSTRK file.