MIA DASD control file filling up with transactions

Products

• MIM Tape Sharing (MIA)
• MIM Resource Sharing (MIM)
• MIM Data Sharing (MII)

Issue/Introduction

You experience excessive MIA DASD control file reserves and the reason seems to be the number of blocks that are in-use in the control file.
Normally 1 block is enough to handle tape drive sharing. Typically the time needed to handle 1 block is 0,003sec.
At the time of the issues the average number of blocks processed is 124 and the time needed is 0,8sec.
You can remediate the problem by migrating to alternate control file and then back to primary control file.

Other potential symptoms:

A triggered Health Check - MIM_DRVR_CF_STATUS@MIA: EXCEPTION-MED INTERVAL

An error indicating the control file is too small...

05:28:26.55 .MIM0055E File 08 - Too small for your systems
05:28:27.32 MIM0095E MIA      MSIERROR CODE=0055 issued by MIMDRDRV.MIMDRCPY+0454
05:28:27.32 .MIM0224I File 07 selected for new primary control file

 

Environment

Release : 12.5
COMMUNICATION=DASDONLY

Cause

MIM 12.5 PTF LU04830 (published 3/23/2022) may prevent certain transactions from being deleted from the control file.
 

Resolution

MIM 12.5 PTF LU06057 (published 6/02/2022) only partially corrects the problem. It deletes old transactions in the first block of the control file, but ignores blocks 2-n .

MIM 12.5 PTF LU10084 (published 5/10/2023) is new fix to correct problem.