My problem is that I have two apps that are both getting these exceptions:
Caused by: org.apache.tomcat.jdbc.pool.PoolExhaustedException: [pool-2-thread-273] Timeout: Pool empty. Unable to fetch a connection in 30 seconds, none available[size:100; busy:99; idle:0; lastwait:30000].
There are two apps:
- grails app war running in tomcat connecting to postgres data source A
- standalone jar connecting to data source B which is a different db on the same server as postgres data source A.
Both apps use org.apache.tomcat.jdbc.pool.ConnectionPool by default it seems (because I didn't configure the default pool anywhere and both apps use this). Also, my max connection limit is 200 and only using < 130 connections, so I'm not hitting a max connection issue. Since two apps are using separate data sources, I read that this would mean they cannot be the same conn pool.
When I login to my postgres server, I can see that app 2 has 100 idle connections and the max idle size of the pool is 100. So this is fine. However, what I was not expecting is that my app 1 would use connections from app 2's pool - or rather, since it appears that apps share a connection pool - I suppose that app 1 is trying to take from this common pool which already has 100 connections allocated. I would not really have expected that because they use a tomcat conn pool and AppB doesn't even use tomcat, so why would they be shared...
So my questions are (since I really am having a hard time finding docs about this):
- Is it accurate that by default different apps would use the same conn pool?
- If they're using the same conn pool then how can they share a conn pool if they're using different data sources?
- Is it possible in grails to specify shared vs unshared conn pool? https://tomcat.apache.org/tomcat-7.0-doc/jndi-datasource-examples-howto.html This link mentions postgres specifically and that it seems like there's shared vs unshared concept (though I can't find any good documentation about this) but it's configured outside of grails. Any way to do it in grails?
Notes: Using grails 2.4.5 and postgres server 90502
