Excessive "reliable Message" waits seen on RAC after a few days uptime

(Doc ID 1990796.1)

Last updated on NOVEMBER 20, 2017

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 12.1]
Information in this document applies to any platform.
"reliable message" waits can exceed 1 second.
This is for a database (non-pluggable).
The problem does not manifest until a few days of up-time
The only workaround is to restart the instance.


Performance is affected severely for example a truncate command can take 20 minutes or more and AWR reports show high wait time for "reliable message".  


A hang analyze will also show 

service name: SYS$BACKGROUND 
     Current Wait Stack: 
      1: waiting for 'CSS group membership query' 

CSS group membership query's are not processed fast enough because of congestion. 


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