The Data and Index components of an IOA Access Method file may extend beyond one physical dataset. When an IOA Access Method file extends to many physical datasets, processing may degrade due to fragmentation overhead. In this case, it is recommended that you reorganize the IOA Access Method file so that the primary and secondary extent datasets are larger. Perform the following steps:
Stop all Control‑D related activities (Control‑D monitor, online activities, batch utilities).
Run utility IOADUL to unload the contents of the Data component to a sequential file. For an example, see member CTDUFDUL in the Control‑D JCL library.
Increase the value specified for parameter SPACE in the relevant DEFxxx and DEFxxxI definition members to specify larger primary and secondary extents. Change this parameter in the definition members of both the Index and Data components.
Delete all dataset extents of the Index and Data components. Perform this step with caution. For an example, see member CTDUFDEL in the Control‑D JCL library.
Run the IOADBF utility with parameter FUNC=INIT to allocate and format the new file’s components using the new parameters. Activate the utility twice, once for the Data component and a second time for the Index component. For an example, see member CTDUFDBF in the Control‑D JCL library.
Run the IOADLD utility to reload contents of the data component from the sequential dataset previously produced by the IOADUL utility. Run the CTDDIB utility to rebuild the index component. For an example, see the CTDUFRST member in the Control‑D JCL library.
Restart Control‑D and all other related activities.
