IT32337: Managed transfers run slowly after upgrading to MQ V9.1 LTS

APAR status

• Closed as program error.

Error description

• In an MQ Managed File Transfer topology:
  
  - An IBM MQ Managed File Transfer for z/OS agent acts as the
  source agent for managed transfers.
  - An IBM MQ Managed File Transfer agent running on Windows acts
  as the destination agent.
  
  Managed transfer requests are submitted to the source agent, to
  transfer a 2GB text file on the mainframe to a network drive
  that is accessible from the Windows system. The managed
  transfers are text transfers, and specify the -dce parameter to
  ensure that the destination agent converts the text data into a
  different code page.
  
  When the destination agent is using MQ V9.0.0.2 Managed File
  Transfer, the managed transfers take approximately 10 minutes to
  complete.
  
  However, after the destination agent is upgraded to use MQ
  V9.1.0.3 Managed File Transfer, the same managed transfers take
  over 15 hours to finish.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of MQ Managed File Transfer who have
  agents that perform:
  
  - Text transfers
  - Message-to-file transfers
  - File-to-message transfers
  - Or transfers involving data sets
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  IBM MQ Managed File Transfer agents that are acting as the
  destination agent for:
  
  - Text transfers
  - Message-to-file transfers
  - File-to-message transfers
  - Or transfers involving data sets
  
  will use either a normal channel or a buffered channel to write
  data to the destination item. When the agent is using a normal
  channel, the FileIOWorker thread associated with the managed
  transfer will write the data to the destination item as soon as
  it is received. If the destination agent is using a buffered
  channel, then the FileIOWorker thread will initially store the
  file data in an internal buffer, and only write the data to the
  destination item once the buffer is full.
  
  Now, MQ V9.1 LTS Managed File Transfer changed the way that
  message-to-file transfers work to ensure that messages were left
  on the source queue if the managed transfer fails. Unfortunately
  one of the changes made to support this new design incorrectly
  modified the behaviour of destination agents so that they would
  never buffer when writing data to a destination item - every
  line or record would be written directly to the destination item
  as soon as it was received.
  
  As a result, the number of write operations made by an MQ V9.1
  LTS Managed File Transfer destination agent would be
  significantly more than the number of write operations performed
  by an MQ V9.0 LTS Managed File Transfer agent. For large files,
  or files that were being written to a remote location such as a
  network drive, this meant that the time taken to perform a
  managed transfer when using MQ V9.1 Managed File Transfer would
  be significantly longer than when using MQ V9.0 Managed File
  Transfer.
  

Problem conclusion

• MQ V9.1 LTS Managed File Transfer has been modified so that
  destination agents will use a buffered channel when performing:
  
  - Text transfers
  - Message-to-file transfers
  - File-to-message transfers
  - Or transfers involving data sets
  
  This means that the time taken for the managed transfers to
  complete when using MQ V9.1 LTS Managed File Transfer will be
  equivalent to the time taken for the same transfer to complete
  when using MQ V9.0 LTS Managed File Transfer.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 CD    TBC.
  v9.1 LTS   9.1.0.6
  
  The latest available MQ 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 MFT V9.1

• Fixed component ID

  5724H7272

Applicable component levels