Trace files jdbc connection pool manager

I created a Spring Aspect which will intercept every database call. This will surely affect the performance. Now, you can easily identify the particular database call which creates connection leak in your application. Thanks Sundararaj Govindasamy for great answer. Call dumpMBean.

Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 5 years, 9 months ago. Active 2 years, 4 months ago. Viewed 50k times. No of active connections No of idle connections No of blocked connections, additional info why this connection is blocked No of available connections and Is there any way to get these info by debugging or using logging frameworks like log4j?

Any idea will be appreciated. Improve this question. Sundararaj Govindasamy. Sundararaj Govindasamy Sundararaj Govindasamy 7, 5 5 gold badges 42 42 silver badges 70 70 bronze badges. Thanks for the hint Nitin — Sundararaj Govindasamy. Add a comment. Active Oldest Votes. Because a connection is unavailable, the Pool Manager creates a new connection for the request. A connection is closed by the application and returned to the connection pool.

Because the number of connections in the connection pool is greater than the minimum pool size, five connections, no action is taken by the Pool Manager. Because the number of connections in the connection pool is greater than the maximum pool size, 10 connections, a connection is closed and discarded from the pool. The Pool Manager detects that a connection was idle in the connection pool longer than the maximum idle timeout. The idle connection is closed and discarded from the pool.

The Pool Manager detects that the number of connections dropped below the limit set by the minimum pool size, five connections. The Pool Manager creates new connections to satisfy the minimum pool size. The driver has to be accessible from the same classloader as tomcat-jdbc. Note that method DataSource.

See alternateUsernameAllowed property for more details. The default value is Default value is maxActive : Idle connections are checked periodically if enabled and connections that been idle for longer than minEvictableIdleTimeMillis will be released.

The connection pool can shrink below this number if validation queries fail. Default value is derived from initialSize : 10 also see testWhileIdle. Default value is Default value is 30 seconds. If the object fails to validate, it will be dropped from the pool, and we will attempt to borrow another. In order to have a more efficient validation, see validationInterval. Default value is false. If an object fails to validate, it will be throw SQLException.

The default value is false. If an object fails to validate, it will be dropped from the pool. String The SQL query that will be used to validate connections from this pool before returning them to the caller. If specified, this query does not have to return any data, it just can't throw a SQLException. The default value is null. If not specified, connections will be validation by the isValid method. This works by calling java. The pool itself doesn't timeout the query, it is still up to the JDBC driver to enforce query timeouts.

A value less than or equal to zero will disable this feature. String The name of a class which implements the org.

Validator interface and provides a no-arg constructor may be implicit. If specified, the class will be used to create a Validator instance which is then used instead of any validation query to validate connections. An example value is com. This value should not be set under 1 second. It dictates how often we check for idle, abandoned connections, and how often we validate idle connections. This value will be overridden by maxAge if the latter is non-zero and lower.

The default value is 5 seconds. The default value is 60 seconds. Access can be achieved by calling unwrap on the pooled connection. DataSource interface, or call getConnection through reflection or cast the object as javax. If set to true a connection is considered abandoned and eligible for removal if it has been in use longer than the removeAbandonedTimeout Setting this to true can recover db connections from applications that fail to close a connection. See also logAbandoned The default value is false.

The default value is 60 60 seconds. The value should be set to the longest running query your applications might have. Logging of abandoned Connections adds overhead for every Connection borrow because a stack trace has to be generated. String The connection properties that will be sent to our JDBC driver when establishing new connections.

String A custom query to be run when a connection is first created. String A semicolon separated list of classnames extending org. JdbcInterceptor class. These interceptors will be inserted as an interceptor into the chain of operations on a java. Connection object. Predefined interceptors: org. ConnectionState - keeps track of auto commit, read only, catalog and transaction isolation level. StatementFinalizer - keeps track of opened statements, and closes them when the connection is returned to the pool.

If a connection is due for validation, but has been validated previously within this interval, it will not be validated again. The default value is 3 seconds. This uses the org. FairBlockingQueue implementation for the list of the idle connections.

The default value is true. This flag is required when you want to use asynchronous connection retrieval. Setting this flag ensures that threads receive connections in the order they arrive. During performance tests, there is a very large difference in how locks and lock waiting is implemented. If the system is running on Linux property os. To disable this Linux specific behavior and still use the fair queue, simply add the property org.

The value should be between The default value is 0 , which implies that connections are eligible for closure as soon as removeAbandonedTimeout has been reached. The default value is 0 , which implies that connections will be left open and no age check will be done upon borrowing from the pool, returning the connection to the pool or when checking idle connections.

This property does not apply to added interceptors as those are configured individually. Default value is 0. Similar to to the removeAbandonedTimeout value but instead of treating the connection as abandoned, and potentially closing the connection, this simply logs the warning if logAbandoned is set to true.

If this value is equal or less than 0, no suspect checking will be performed. Suspect checking only takes place if the timeout value is larger than 0 and the connection was not abandoned or if abandon check is disabled.

The pool can however be configured to allow use of different credentials each time a connection is requested. To enable the functionality described in the DataSource. This way, the pool size is still managed on a global level, and not on a per schema level.

This property was added as an enhancement to bug DataSource Inject a data source to the connection pool, and the pool will use the data source to retrieve connections instead of establishing them using the java. Driver interface. This is useful when you wish to pool XA connections or connections established using a data source instead of a connection string.

Default value is null. See the dataSource attribute. This prevents a thread holding on to a reference of a connection it has already called closed on, to execute queries on it. Default value is true.

Default value is false for backwards compatibility. Set to true if you want to ignore error of connection creation while initializing the pool. Set to false if you want to fail the initialization of the pool by throwing exception. To see an example of how to use an interceptor, take a look at org. This simple interceptor is a cache of three attributes, transaction isolation level, auto commit and read only state, in order for the system to avoid not needed roundtrips to the database.

Further interceptors will be added to the core of the pool as the need arises. Contributions are always welcome!

Interceptors are of course not limited to just java. Connection but can be used to wrap any of the results from a method invocation as well. You could build query performance analyzer that provides JMX notifications when a query is running longer than the expected time.

The property contains a list of semicolon separated class names. If the classname is not fully qualified it will be prefixed with the org. ConnectionState; org. Interceptors can have properties as well.