RP/MSQ 4.0A(VMS), 5.0(VMS) - Missed message and PAMS_NOTALLOCATE error by the SBS server (Doc ID 770843.1)

Last updated on NOVEMBER 03, 2016

Applies to:

Oracle MessageQ / MessageQ / 4.0A, 5.0VMS)
Information in this document applies to any platform

Goal

Missed message on MOT #1, with a PAMS_NOTALLOCATE error in the DMQ$EVL log file. The following combination of MOT
senders/receivers are required to see the problem:
 
  o On Processor A, a process sending to MOT #1
  o On Processor A, at least one process registered to receive on MOT #1
  o On Processor B, a process sending to MOT #2
  o On Processor A, at least one process registered to receive on MOT #2
  o Both MOTs must be configured for optimized Ethernet mode (DG/ETH)
 
When the problem occurs, the process on Processor A misses a message on MOT #1, and there is a PAMS__NOTALLOCATE error
in the DMQ$EVL log file. Use SBSWITCH TRACE to turn on tracing; the pattern appears to be that when the missed message
occurred was when the SBS Server on Processor A was in the process of trying to distribute a message on MOT #1 when it
is interrupted by a message from the LAN for MOT #2, which is distributed locally. When the original thread resumes,
the NOTALLOCATE error occurs when the SBS Server tries to send the first message to the locally subscribed process. It
appears that the AST thread is using a resource that the main thread is also using, and the two threads interfere.

Solution

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