Files can grow unnecessarily large when space left by deleted records builds up. This space is left behind when a record is deleted so that the file can maintain the relative record number (RRN) of the remaining records. Relative record numbers are used by the operating system and by MIMIX products to locate records within a physical file.
The Assure MIMIX Promoter Reorganize Active File (RGZACTF) command removes deleted records from members of a physical file while the file is actively being updated and compresses the data. This reduces the offline time for the file to a fraction of the update time.
To reorganize an active file, the RGZACTF request creates a temporary duplicate copy of the file to be reorganized using IBM save and restore operations. The save and restore process allows the file identifier to be preserved while the file is reorganized. Copy active file processing copies data from the original file and removes deleted records from the temporary file while ensuring that any changes to the original file are incorporated. When the copy operation is complete, the reorganize operation resumes control, acquires a lock on the original file, then replaces the original file with the reorganized, up-to-date temporary copy. The following figure shows this process.
Figure 2.The Reorganize Active File Process.
When you specify a request to reorganize a file, you can request to save a copy of the original file in a save file.