JR32052: SDLC HANG CONDITION CAUSING ALL PROCESSING TO HALT.

Communications Server for Windows, Version 6.1.3 -- Latest Fixpack

APAR status

• Closed as program error.

Error description

• Customer running SDLC connectivity to the host and reports a
  application HANG condition.
  

Local fix

• cycle sna node.
  

Problem summary

• Customers running APPC applications that send and receive large
  amounts of data to / from the host can see a HANG condition
  where all processing stops.
  The traces show all READ verbs waiting for data from remote
  application. Internal trace show all data sent to the DLC, but
  no incoming data is rececived.
  

Problem conclusion

• The problem occurs when multiple transactions are running
  simultaneously, sending and receiving data on multiple sessions.
  The sdlc code uses a variable called ConfirmationsOwed to track
  and handle the data sent and received. The variable was not
  synchronized across all threads thereby causing intermittent
  HANGS.
  The problem was resolved by synchronizing the variable across
  all threads.
  

Temporary fix

• 01/16/2009
  

Comments

APAR Information

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

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

Modules/Macros

• PDLNDSDL PDLNEMAP
  

Fix information

• Fixed component name

  COMM SERV NT 6.

• Fixed component ID

  5639F2503

Applicable component levels

• R612 PSN

     UP

• R613 PSN

     UP