Minimized journal entry data - assure_mimix - 10.0

Assure MIMIX Administrator Reference

Product type
Software
Portfolio
Integrate
Product family
Assure
Product
Assure MIMIX™ Software
Version
10.0
Language
English
Product name
Assure MIMIX
Title
Assure MIMIX Administrator Reference
Copyright
2023
First publish date
1999
ft:lastEdition
2024-05-07
ft:lastPublication
2024-05-07T13:36:02.962500

MIMIX supports the ability to process minimized journal entries placed in a user journal for object types of file (*FILE) and data area (*DTAARA).

The IBM i provides the ability to create journal entries using an internal format that minimizes the data specific to these object types that are stored in the journal entry. This support is enabled in the MIMIX create or change journal definitions commands and built using the Build Journal Environment (BLDJRNENV) command.

When a journal entry for one of these object types is generated, the system compares the size of the minimized format to the standard format and places whichever is smaller in the journal. For database files, only update journal entries (R-UP and R-UB) and rollback-type update entries (R-BR and R-UR) can be minimized.

If MINENTDTA(*FILE) or MINENTDTA(*FLDBDY) is in effect and a database record includes LOB fields, LOB data is journaled only when that LOB is changed. Changes to other fields in the record will not cause the LOB data to be journaled unless the LOB is also changed. When database files have records with static LOB values, minimized journal entries can produce considerable savings.

The benefit of using minimized journal entries is that less data is stored in the journal. In a MIMIX replication environment, you also benefit by having less data sent over communications lines and saved in MIMIX log spaces. Factors in your environment such as the percentage of journal entries that are updates (R-UP), the size of database records, the number of bytes typically changed in an update, may influence how much benefit you achieve.