New to HikariCP, maximumPoolSize = 1

[Roberto Ferreras]

Hi.

I'm migrating an application from Tomcat JDBC pool to HikariCP.

The tests run inside an in memory H2 database.

When configuring the test's DataSource I set maximumPoolSize to 1 as I had been using until now.

But when trying to run them I get the error "Connection is not available, request timed out after 30000ms."

Setting maximumPoolSize to 2 or more works as expected.

Then I tried the production configuration with MySQL and got the same results.

Is there something I am missing or maximumPoolSize = 1 should just work?

Thanks.

[Brett Wooldridge]

It should work. Can you enable debug logging for the com.zaxxer.hikari package and post the logs from the first minute, as well as the timeout exception?

[Roberto Ferreras]

This is with maximumPoolSize = 1:

2016-10-21 13:50:55,019 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbcPool - configuration:
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - allowPoolSuspension.............false
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - autoCommit......................false
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - catalog.........................null
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionInitSql...............null
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTestQuery.............null
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTimeout...............30000
2016-10-21 13:50:55,030 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSource......................null
2016-10-21 13:50:55,031 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceClassName............."org.h2.jdbcx.JdbcDataSource"
2016-10-21 13:50:55,031 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceJNDI..................null
2016-10-21 13:50:55,084 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceProperties............{password=<masked>, url=jdbc:h2:mem:test;IGNORECASE=TRUE;COLLATION=DEFAULT_ STRENGTH PRIMARY}
2016-10-21 13:50:55,084 [main] DEBUG com.zaxxer.hikari.HikariConfig - driverClassName.................null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckProperties...........{}
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckRegistry.............null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - idleTimeout.....................600000
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - initializationFailFast..........true
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - isolateInternalQueries..........false
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbc4ConnectionTest.............false
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbcUrl.........................null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - leakDetectionThreshold..........0
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - maxLifetime.....................1800000
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - maximumPoolSize.................1
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricRegistry..................null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricsTrackerFactory...........null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - minimumIdle.....................1
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - password........................<masked>
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - poolName........................"jdbcPool"
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - readOnly........................false
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - registerMbeans..................false
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - scheduledExecutorService........null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - threadFactory...................null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - transactionIsolation............null
2016-10-21 13:50:55,085 [main] DEBUG com.zaxxer.hikari.HikariConfig - username........................null
2016-10-21 13:50:55,086 [main] DEBUG com.zaxxer.hikari.HikariConfig - validationTimeout...............5000
2016-10-21 13:50:55,088 [main] INFO  com.zaxxer.hikari.HikariDataSource - jdbcPool - Started.
2016-10-21 13:50:55,358 [main] INFO  com.zaxxer.hikari.pool.PoolBase - jdbcPool - Driver does not support get/set network timeout for connections. (org.h2.jdbc.JdbcConnection.getNetworkTimeout()I)
2016-10-21 13:50:55,480 [jdbcPool housekeeper] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Pool stats (total=0, active=0, idle=0, waiting=0)
2016-10-21 13:50:55,492 [jdbcPool connection adder] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Added connection conn1: url=jdbc:h2:mem:test user=
2016-10-21 13:50:55,492 [jdbcPool connection adder] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - After adding stats (total=1, active=0, idle=1, waiting=0)
2016-10-21 13:50:58,834 [main] DEBUG com.zaxxer.hikari.pool.PoolBase - jdbcPool - Reset (autoCommit) on connection conn1: url=jdbc:h2:mem:test user=
2016-10-21 13:51:25,486 [jdbcPool housekeeper] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Pool stats (total=1, active=1, idle=0, waiting=1)
2016-10-21 13:51:34,057 [main] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Timeout failure stats (total=1, active=1, idle=0, waiting=0)
2016-10-21 13:51:34,058 [main] WARN  org.hibernate.engine.jdbc.spi.SqlExceptionHelper - SQL Error: 0, SQLState: null
2016-10-21 13:51:34,058 [main] ERROR org.hibernate.engine.jdbc.spi.SqlExceptionHelper - jdbcPool - Connection is not available, request timed out after 30001ms.
2016-10-21 13:51:34,140 [Thread-3] INFO  com.zaxxer.hikari.pool.HikariPool - jdbcPool - Close initiated...
2016-10-21 13:51:34,140 [Thread-3] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Before closing stats (total=1, active=0, idle=1, waiting=0)
2016-10-21 13:51:34,141 [jdbcPool connection closer] DEBUG com.zaxxer.hikari.pool.PoolBase - jdbcPool - Closing connection conn1: url=jdbc:h2:mem:test user=: (connection evicted)
2016-10-21 13:51:34,142 [Thread-3] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - After closing stats (total=0, active=0, idle=0, waiting=0)
2016-10-21 13:51:34,143 [Thread-3] INFO  com.zaxxer.hikari.pool.HikariPool - jdbcPool - Closed.

And this is with maximumPoolSize = 2:

2016-10-21 13:53:54,053 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbcPool - configuration:
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - allowPoolSuspension.............false
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - autoCommit......................false
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - catalog.........................null
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionInitSql...............null
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTestQuery.............null
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTimeout...............30000
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSource......................null
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceClassName............."org.h2.jdbcx.JdbcDataSource"
2016-10-21 13:53:54,061 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceJNDI..................null
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceProperties............{password=<masked>, url=jdbc:h2:mem:test;IGNORECASE=TRUE;COLLATION=DEFAULT_ STRENGTH PRIMARY}
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - driverClassName.................null
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckProperties...........{}
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckRegistry.............null
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - idleTimeout.....................600000
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - initializationFailFast..........true
2016-10-21 13:53:54,102 [main] DEBUG com.zaxxer.hikari.HikariConfig - isolateInternalQueries..........false
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbc4ConnectionTest.............false
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbcUrl.........................null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - leakDetectionThreshold..........0
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - maxLifetime.....................1800000
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - maximumPoolSize.................2
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricRegistry..................null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricsTrackerFactory...........null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - minimumIdle.....................2
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - password........................<masked>
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - poolName........................"jdbcPool"
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - readOnly........................false
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - registerMbeans..................false
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - scheduledExecutorService........null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - threadFactory...................null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - transactionIsolation............null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - username........................null
2016-10-21 13:53:54,103 [main] DEBUG com.zaxxer.hikari.HikariConfig - validationTimeout...............5000
2016-10-21 13:53:54,104 [main] INFO  com.zaxxer.hikari.HikariDataSource - jdbcPool - Started.
2016-10-21 13:53:54,329 [main] INFO  com.zaxxer.hikari.pool.PoolBase - jdbcPool - Driver does not support get/set network timeout for connections. (org.h2.jdbc.JdbcConnection.getNetworkTimeout()I)
2016-10-21 13:53:54,446 [jdbcPool housekeeper] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Pool stats (total=0, active=0, idle=0, waiting=0)
2016-10-21 13:53:54,451 [jdbcPool connection adder] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Added connection conn1: url=jdbc:h2:mem:test user=
2016-10-21 13:53:54,452 [jdbcPool connection adder] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Added connection conn2: url=jdbc:h2:mem:test user=
2016-10-21 13:53:54,452 [jdbcPool connection adder] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - After adding stats (total=2, active=0, idle=2, waiting=0)
2016-10-21 13:53:57,601 [main] DEBUG com.zaxxer.hikari.pool.PoolBase - jdbcPool - Reset (autoCommit) on connection conn1: url=jdbc:h2:mem:test user=
2016-10-21 13:54:03,786 [Thread-3] INFO  com.zaxxer.hikari.pool.HikariPool - jdbcPool - Close initiated...
2016-10-21 13:54:03,787 [Thread-3] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - Before closing stats (total=2, active=0, idle=2, waiting=0)
2016-10-21 13:54:03,788 [jdbcPool connection closer] DEBUG com.zaxxer.hikari.pool.PoolBase - jdbcPool - Closing connection conn1: url=jdbc:h2:mem:test user=: (connection evicted)
2016-10-21 13:54:03,788 [jdbcPool connection closer] DEBUG com.zaxxer.hikari.pool.PoolBase - jdbcPool - Closing connection conn2: url=jdbc:h2:mem:test user=: (connection evicted)
2016-10-21 13:54:03,788 [Thread-3] DEBUG com.zaxxer.hikari.pool.HikariPool - jdbcPool - After closing stats (total=0, active=0, idle=0, waiting=0)
2016-10-21 13:54:03,789 [Thread-3] INFO  com.zaxxer.hikari.pool.HikariPool - jdbcPool - Closed.