The system is 800xA 5.1 Rev A with 2 AS and 4 CS (2 redundant pairs). The connectivity is Advant Master. The (physical one) MB300 is virtual divided into 2 networks, the event filtering is set with NODE_DESCR elements.
I have the problem that all OPC-DA subsciptions are really fast but the alarms/events (as OPC A&E) are delayed for up to 20 seconds.
That means, I set an alarm state, I see in that moment it happens in graphic elements but for the alarm list it takes some time. The same behavior if I quit that alarm.
I have restarted all connectivity server and the Alarm Managers. All services are "green", the affinity is set like the manual says.
Any idea? Thank you in advance!
Voted best answer
Sounds like you have a backpressure situation on the MB300.
The flow of A/E on MB300 is capped by the slowest recipient (RTA board). If one RTA board is totally saturated with OPC subscriptions, it could theoretically cause delays in A/E delivery.
Logon to all controllers and all RTA/PU410 with OnLine Builder and look for System Messages (remember that they can be directed to log only and will then not show on screen).
Look for "24 5" messages indicating lack of resources. Attach full detail here if you want additional help.
As a precaution, RTAs not needing A/E should be removed from the controller's MasterView Table using the NODE_DESCR option of SafeGuard (also available w/o SafeGuard installed).