One of our apps has started throwing intermittent connection errors which show
up as:
Could not open JDBC Connection for transaction; nested exception is
org.jboss.util.NestedSQLException: No ManagedConnections available within
configured blocking timeout ( 5000 [ms] ); - nested throwable:
(javax.resource.ResourceException: No ManagedConnections available within
configured blocking timeout ( 5000 [ms] )))
Database activity during the time was quite low, certainly far less than peak.
Also the highwater number of connections from v$license is about 20% of the
processes parameter.
However it occurred to me that there are 7 other databases on that server and
even more on the cluster as a whole, a mix of standalone, rac one node and full
rac. It's possible one or more of the other databases had a rush of concurrent
connections at that same time which brought us above the queuesize default
limit. Of course it's also possible that this is a dead end and has nothing to
do with the problem.
So I think my question needs to be - is there any way to query the number of
concurrent connections a given listener experienced in a given time period? So
far the only method I came up with is to go through the listener log file and
count each connection at that time manually. I'd rather not do that. Or if
anyone has a suggestion for a different approach I'd be happy to hear it.
This database is RAC One Node 11.2.0.3 running on red hat linux 6.2
Thank you!
Jay Miller
Sr. Oracle DBA
Database Engineering
