My app uses Hibernate and c3po, and isn't starting under windows 10 + eclipse Oxygen + Tomcat 8, while under Linux works fine with the same configuration.
These are some lines the console shows when starting Tomcat
2017/11/27 18:21:03 WARN com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@15cc07ce -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
This should a connection problem as reported here .
This seems confirmed by an exception I get:
2017/11/27 18:21:14 WARN com.mchange.v2.resourcepool.BasicResourcePool - com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@1e723184 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
org.postgresql.util.PSQLException: FATALE: the remaining connection slots are reserveed to non replica superusers connections
at org.postgresql.core.v3.ConnectionFactoryImpl.readStartupMessages(ConnectionFactoryImpl.java:469)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:112)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:66)
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:125)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:30)
at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:22)
at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:30)
at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
From postgresql log I see there are many connection until the db says it cannot allocate more. The connections are far above 10, while I have this in my hibernate.cfg.xml
<property name="hibernate.c3p0.min_size">1</property>
<property name="hibernate.c3p0.max_size">3</property>
<property name="hibernate.c3p0.timeout">1800</property>
<property name="hibernate.c3p0.max_statements">50</property>
<property name="hibernate.c3p0.idle_test_period">3000</property>
psql -h localhost -U user db works fine
I used Wireshark and RawCap under Windows to capture the connections and it seems the connections are acquired, as the log says, but after seeing Postgres saying "ready for queries", they are closed, if I saw well.
What else can I look at to debug what's happening??
It turned out that I was using the wrong postgresql driver. I have java 8, and using PostgreSQL JDBC 4.2 Driver, 42.1.4 solved the issue.