Structure of the IOA Conditions file

The IOA Conditions file is comprised of the following parts:

• 1 physical record for synchronization purposes.
• 32 logical records for prerequisite conditions, as follows:
  • 31 logical records; one for each day of the month.
  • 1 logical record for STAT conditions.

The record size, in bytes, of a physical record in the IOA Conditions file is fixed at 32 KB.

The CNDREC# parameter specifies the number of physical records in each logical record.

Each prerequisite condition requires 24 bytes. Therefore, the number of conditions allowed for each date is equal to 1/24 of the 32 KB times the value specified for the CNDREC# parameter. You can also use long condition names. Each long condition name occupies two entries, or 48 bytes each.

Due to MVS access method limitations, a maximum of 32KB bytes can be specified for the record size of a physical record in the IOA Conditions file. This default value is the maximum block size for 3380 disks and 3390 DASD devices. This default allows a maximum of 1365 conditions in each prerequisite condition record of the IOA Conditions file.

If your site uses a large number of conditions such as OUT conditions created by Control‑M, and you require more than the maximum 32KB for each record in the IOA Conditions file, additional slots can be allowed for each record. For more information about this option, see "CNDREC#" in Parameters.

Use the following formula to calculate the region size needed for the IOA Conditions file:

32760 * ((32 * CNDREC#) + 2 + INT((CNDREC# - 1 ) / 255) )

The following examples illustrate the use of the formula:

• If CNDREC# is set to 1, about 1.11 MB of virtual storage is needed to load the IOA Conditions file.
• If CNDREC# is set to 2, about 2.16 MB of virtual storage is needed to load the IOA Conditions file.

For more information about the CNDREC# parameter, see Step 5 – Specify target configuration parameters.