How much storage does the SYSB-AJR journal require?
If you’re journaling changes to VSAM KSDS files, then SYSB-AJR only journals the information that has changed and would be needed to recover to the before image. If you’re journaling changes to a VSAM RLS nonrecoverable file, then SYSB-AJR journals the entire before image. This process ensures full data integrity during recovery because other tasks could modify a nonrecoverable VSAM RLS data set.
The amount of information a journal can hold depends on several factors such as file type, record size, and the number of changes the batch step or steps (in multistep recovery) update. To optimize your journaling, H&W can help you specify a size adequate for your needs. You can also analyze trends and support growing workloads using the statistics that SYSB-AJR writes to your job logs.