MIM task using HIGH CPU utilizing XES LIST STRUCTURES

Products

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

Issue/Introduction

You recently split two LPARs out of one sysplex into two separate plexes.  Your performance team reported a much higher CPU usage rate for the CAMIMGR started task on the AAA LPAR.  

You have a DASDONLY configuration with both DASD and CF structures.  For the split, you created new COUPLE datasets and wrote out a new CFRM policy which included defining the MII structures.  They are defined identically to the current sysplex STRs.  You reused the existing DASD CKPT datasets.  

Thinking that perhaps you needed to perform a FORMAT of the DASD CKPT, you tried starting MIM with FORMAT=BOTH but this made no difference.

      14.04.49 AAAA           @d files
      14.04.49 AAAA           MIM0067I Command DISPLAY
      MIM0102I Control File Display:
         File Unit Status  Volser   Data Set
          00       IN-USE  ####### MIM_LST_STR_CF00
          01       USABLE  ####### MIM_LST_STR_CF01
          02  7436 USABLE  ####### MIM.MII.CF02

      MIM0104I Checkpoint File Display:
         File Unit Status  Volser   Data Set
          00  7411 IN-USE  ######   MIM.AAAA.CKPT00
          01  7411 USABLE  ######   MIM.AAAA.CKPT01

 

Resolution

Check whether DYNAMIC CF DISPATCHING is enabled. May need to change it to THIN INTERRUPTS (DYNDISP=THIN).