MarkView Admin - System Status queries return a false over-limit status in a RAC environment.
12065
Summary
12065
Applies To
- ERP System: Oracle, SAP
- MarkView Version: All
Behavior
- In an Oracle RAC environment, Status Lookups which query v$session can provide misleading results. It is likely that these status queries will falsely indicate an over-limit condition. This may in turn lead to duplicate status emails being generated in error. The standard delivered Status Lookups affected are:
- Disconnected Bar Code Server
- Disconnected Fax Server
- Disconnected Import Server
Cause
- Although the
v$
views continue to exist in Oracle environments where RAC is implemented, they do not span all nodes in the cluster. As a consequence, a Status Lookup query will report an over-limit condition if it runs on a different node to that where the queried program is running.
Resolution
With Oracle RAC implemented, there exists gv$ views (e.g. gv$instance
, gv$session
) which span all nodes in the cluster. Therefore, to resolve the issue, Status Lookup queries can be modified to query the gv$session view rather than the v$session view.
For example, the original and modified query behind the Status Lookup 'Disconnected Bar Code Server' is shown below:
select decode(count(distinct(program)),1,0,1) from v$session where upper(program) ='MVBARSVR.EXE' -
original
select decode(count(distinct(program)),1,0,1) from gv$session where upper(program) ='MVBARSVR.EXE'
new
Keywords: v$session, gv$session, "status lookups", "system status"