If the system ends abnormally, during the next initial program load (IPL), the system automatically lists those files that require access path recovery. You can control when access paths are rebuilt.
You can decide whether to rebuild the access path:
The IPL threshold value determines which access paths to rebuild during the IPL. All access paths with a sequence value that is less than or equal to the IPL threshold value rebuild during the IPL. Changing the IPL threshold value to 99 means that all access paths with a sequence value of 1 through 99 rebuild during the IPL. Changing the IPL threshold value to 0 means that no access paths rebuild until after the system completes its IPL, except those access paths that were being journaled and those access paths for system files.
The access path recovery value for a file is determined by the value you specified for the RECOVER parameter on the create and change file commands. The default recovery value for *IPL (rebuild during IPL) is 25 and the default value for AFTIPL (rebuild after IPL) is 75; therefore, RECOVER(*IPL) will show as 25. The initial IPL threshold value is 50; this allows the parameters to affect when the access path is rebuilt. You can override this value on the Edit Rebuild of Access Paths display.
If a file is not needed immediately after IPL time, specify that the file can be rebuilt at a later time. This should reduce the number of access paths that need to be rebuilt at IPL, allowing the system to complete its IPL much faster.
For example, you can specify that all files that must have their access paths rebuilt should rebuild the access paths when the file is first used. In this case, no access paths are rebuilt at IPL. You can control the order in which the access paths are rebuilt by running only those programs that use the files you want to rebuild first. This method shortens the IPL time and can make the first of several applications available faster. However, the overall time to rebuild access paths probably is longer. (Other work might be running when the access paths are being rebuilt, and there might be less main storage available to rebuild the access paths).