IT37646: RSS_FLOW_CONTROL ALWAYS ENABLED EVEN THOUGH SET TO DISABLED

APAR status

• Closed as program error.

Error description

• When RSS_FLOW_CONTROL is set to -1 (disabled) under 12.10.FC14
  onstat -g rss verbose shows RSS_FLOW_CONTROL as enabled with the
  effective setting as 0.
  
  This is compounded by the fact that when set to 0 "minimal"
  defaults are in place (Start Flow Control at 12 * LOGBUFF / Stop
  Flow Control at 11 * LOGBUFF); so a client who DOES NOT WANT
  flow control at all (-1) actually gets flow control occurring at
  a (relatively) low RSS lag resulting in the PRIMARY stalling due
  to flow control.
  
  Does not occur under 12.10.FC13 or 14.10.FC6
  

Local fix

• A possible mitigation is to set RSS_FLOW_CONTROL to high values:
  RSS_FLOW_CONTROL=2048M,1870M
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of Informix Server prior to 12.10.xC15 and 14.10.xC7.  *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Informix Server 12.10.xC15 or 14.10.xC7 (when     *
  * available).                                                  *
  ****************************************************************
  

Problem conclusion

• Fixed in Informix Server 12.10.xC15 and 14.10.xC7.
  

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

  INFORMIX SERVER

• Fixed component ID

  5725A3900

Applicable component levels