IT24818: The dmpmqmsg utility hangs with high CPU usage

APAR status

• Closed as program error.

Error description

• If the dmpmqmsg utility is called programmatically with no stdin
  stream and is attempting to write to a file which already
  exists, the utility hangs with high CPU usage, utilising
  resources until the disk becomes filled up.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of IBM MQ running the runmqras utility with "-section
  cluster" or who are using dmpmqmsg utility programmatically.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  If the dmpmqmsg utility attempts to write to a file which
  already exists, it prompts the user to provide their
  confirmation that the existing file may be overwritten.
  
  If there was no stdin stream on which to obtain the user's
  input, then a coding error caused the dmpmqsg utility to enter
  an infinite loop. This loop caused high CPU usage to be
  overserved from the dmpmqmsg utility.
  

Problem conclusion

• The dmpmqmsg logic for handling an output file that already
  exists has been fixed by ensuring that the failure to read from
  stdin will terminate the program with a "File already exists"
  error.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.10
  v9.0 LTS   9.0.0.5
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  IBM MQ BASE MP

• Fixed component ID

  5724H7251

Applicable component levels