I am trying to get connection from ComboPooledDataSource, but let's say I made a typo in the password. I would like to get the information about the actual error cause, but all I can from the thrown exception is that something went wrong. Is there a way to find out what the real problem is, in form of a String that can be displayed to the user?
I am using c3po-0.9.1.2.
Let's be concrete, my code looks like this:
ComboPooledDataSource ds = new ComboPooledDataSource();
ds.setDriverClass("org.postgresql.Driver");
ds.setJdbcUrl("jdbc:postgresql://localhost:5432/my_db");
ds.setUser("user1");
ds.setPassword("wrong-password");
try {
Connection c = ds.getConnection();
...
} catch (Exception e) {
e.printStackTrace();
}
The ds.getConnection() code throws an exception, which prints the following stakctrace:
java.sql.SQLException: Connections could not be acquired from the underlying database!
at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:529)
at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
at test.ConnectionErrorDemo.main(ConnectionErrorDemo.java:21)
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1319)
at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:557)
at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:477)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:525)
... 2 more
So, this exception is not helpful at all, as it does not say anything about the actual cause of the problem. However, in the console you can also see log entries like this, which describe the actual problem:
WARNING: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask#249939c3 -- 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: FATAL: password authentication failed for user "user1"
at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:398)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:173)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:64)
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:136)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:29)
at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:21)
at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:31)
at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
at org.postgresql.Driver.connect(Driver.java:267)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
If I understand that correctly, this log entry is done by the c3po library itself, an therefore I thought maybe there is a way to access this information somehow. Any ideas?
Related
Like mentioned here we have almost the same issues with a java project (playframework) with neo4j-ogm and the ogm-bolt-driver (3.2.27). Connection resets sometimes, throws exception and reconnects with the next request (mostly).
The nodes will be queried from database via repositories and neo4j-ogm session (will be opened for small pieces of work).
Any advice will be appreciated.
play.api.UnexpectedException: Unexpected exception[ConnectionException: Connection to the database failed]
at play.api.http.HttpErrorHandlerExceptions$.throwableToUsefulException(HttpErrorHandler.scala:358)
at play.api.http.DefaultHttpErrorHandler.onServerError(HttpErrorHandler.scala:264)
at play.core.server.AkkaHttpServer$$anonfun$2.applyOrElse(AkkaHttpServer.scala:430)
at play.core.server.AkkaHttpServer$$anonfun$2.applyOrElse(AkkaHttpServer.scala:422)
at scala.concurrent.impl.Promise$Transformation.run(Promise.scala:454)
at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:63)
at akka.dispatch.BatchingExecutor$BlockableBatch.$anonfun$run$1(BatchingExecutor.scala:100)
at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.scala:18)
at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:94)
at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:100)
at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:49)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(ForkJoinExecutorConfigurator.scala:48)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1016)
at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1665)
at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1598)
at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)
Caused by: org.neo4j.ogm.exception.ConnectionException: Connection to the database failed
at org.neo4j.ogm.drivers.bolt.driver.BoltDriverExceptionTranslator.translateExceptionIfPossible(BoltDriverExceptionTranslator.java:38)
at org.neo4j.ogm.session.Neo4jSession.doInTransaction(Neo4jSession.java:601)
at org.neo4j.ogm.session.Neo4jSession.doInTransaction(Neo4jSession.java:558)
at org.neo4j.ogm.session.delegates.LoadOneDelegate.load(LoadOneDelegate.java:87)
at org.neo4j.ogm.session.delegates.LoadOneDelegate.load(LoadOneDelegate.java:53)
at org.neo4j.ogm.session.Neo4jSession.load(Neo4jSession.java:178)
at modules.shared.repositories.CrudRepository.find(CrudRepository.java:50)
at config.secured.Secured.getUserFromSession(Secured.java:88)
at config.secured.Secured.getUser(Secured.java:56)
at config.secured.Secured.getUser(Secured.java:39)
at config.secured.DataWizardSecurity$AuthenticatedAction.call(DataWizardSecurity.java:63)
at config.filter.SafeFormFactoryToRequest.call(SafeFormFactoryToRequest.java:24)
at config.filter.Messaged.call(Messaged.java:29)
at play.core.j.JavaAction.$anonfun$apply$8(JavaAction.scala:175)
at scala.concurrent.Future$.$anonfun$apply$1(Future.scala:672)
at scala.concurrent.impl.Promise$Transformation.run(Promise.scala:431)
at play.core.j.HttpExecutionContext.$anonfun$execute$1(HttpExecutionContext.scala:64)
at play.api.libs.streams.Execution$trampoline$.execute(Execution.scala:70)
at play.core.j.HttpExecutionContext.execute(HttpExecutionContext.scala:59)
at scala.concurrent.impl.Promise$Transformation.submitWithValue(Promise.scala:393)
at scala.concurrent.impl.Promise$DefaultPromise.submitWithValue(Promise.scala:302)
at scala.concurrent.impl.Promise$DefaultPromise.dispatchOrAddCallbacks(Promise.scala:276)
at scala.concurrent.impl.Promise$DefaultPromise.map(Promise.scala:146)
at scala.concurrent.Future$.apply(Future.scala:672)
at play.core.j.JavaAction.apply(JavaAction.scala:176)
at play.api.mvc.Action.$anonfun$apply$4(Action.scala:82)
at play.api.libs.streams.StrictAccumulator.$anonfun$mapFuture$4(Accumulator.scala:168)
at scala.util.Try$.apply(Try.scala:210)
at play.api.libs.streams.StrictAccumulator.$anonfun$mapFuture$3(Accumulator.scala:168)
at scala.Function1.$anonfun$andThen$1(Function1.scala:85)
at scala.Function1.$anonfun$andThen$1(Function1.scala:85)
at scala.Function1.$anonfun$andThen$1(Function1.scala:85)
at scala.Function1.$anonfun$andThen$1(Function1.scala:85)
at scala.Function1.$anonfun$andThen$1(Function1.scala:85)
at play.api.libs.streams.StrictAccumulator.run(Accumulator.scala:199)
at play.core.server.AkkaHttpServer.$anonfun$runAction$4(AkkaHttpServer.scala:417)
at akka.http.scaladsl.util.FastFuture$.strictTransform$1(FastFuture.scala:41)
at akka.http.scaladsl.util.FastFuture$.$anonfun$transformWith$3(FastFuture.scala:51)
at scala.concurrent.impl.Promise$Transformation.run(Promise.scala:448)
... 12 common frames omitted
Caused by: org.neo4j.driver.exceptions.ServiceUnavailableException: Connection to the database failed
at org.neo4j.driver.internal.util.Futures.blockingGet(Futures.java:143)
at org.neo4j.driver.internal.InternalSession.beginTransaction(InternalSession.java:98)
at org.neo4j.driver.internal.InternalSession.beginTransaction(InternalSession.java:92)
at org.neo4j.ogm.drivers.bolt.transaction.BoltTransaction.newOrExistingNativeTransaction(BoltTransaction.java:62)
at org.neo4j.ogm.drivers.bolt.transaction.BoltTransaction.<init>(BoltTransaction.java:50)
at org.neo4j.ogm.drivers.bolt.driver.BoltDriver.lambda$null$0(BoltDriver.java:128)
at org.neo4j.ogm.session.transaction.DefaultTransactionManager.openTransaction(DefaultTransactionManager.java:75)
at org.neo4j.ogm.session.Neo4jSession.beginTransaction(Neo4jSession.java:530)
at org.neo4j.ogm.session.Neo4jSession.doInTransaction(Neo4jSession.java:580)
... 49 common frames omitted
Suppressed: org.neo4j.driver.internal.util.ErrorUtil$InternalExceptionCause: null
at org.neo4j.driver.internal.async.inbound.ChannelErrorHandler.transformError(ChannelErrorHandler.java:127)
at org.neo4j.driver.internal.async.inbound.ChannelErrorHandler.fail(ChannelErrorHandler.java:113)
at org.neo4j.driver.internal.async.inbound.ChannelErrorHandler.exceptionCaught(ChannelErrorHandler.java:99)
at org.neo4j.driver.internal.shaded.io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:302)
at org.neo4j.driver.internal.shaded.io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:281)
at org.neo4j.driver.internal.shaded.io.netty.channel.AbstractChannelHandlerContext.fireExceptionCaught(AbstractChannelHandlerContext.java:273)
at org.neo4j.driver.internal.shaded.io.netty.channel.DefaultChannelPipeline$HeadContext.exceptionCaught(DefaultChannelPipeline.java:1377)
at org.neo4j.driver.internal.shaded.io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:302)
at org.neo4j.driver.internal.shaded.io.netty.channel.AbstractChannelHandlerContext.invokeExceptionCaught(AbstractChannelHandlerContext.java:281)
at org.neo4j.driver.internal.shaded.io.netty.channel.DefaultChannelPipeline.fireExceptionCaught(DefaultChannelPipeline.java:907)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.handleReadException(AbstractNioByteChannel.java:125)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:177)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
at org.neo4j.driver.internal.shaded.io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986)
at org.neo4j.driver.internal.shaded.io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at org.neo4j.driver.internal.shaded.io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.base/java.lang.Thread.run(Thread.java:832)
Caused by: java.net.SocketException: Connection reset
at java.base/sun.nio.ch.SocketChannelImpl.throwConnectionReset(SocketChannelImpl.java:345)
at java.base/sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:376)
at org.neo4j.driver.internal.shaded.io.netty.buffer.PooledByteBuf.setBytes(PooledByteBuf.java:253)
at org.neo4j.driver.internal.shaded.io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1132)
at org.neo4j.driver.internal.shaded.io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:350)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:151)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581)
at org.neo4j.driver.internal.shaded.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
at org.neo4j.driver.internal.shaded.io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986)
at org.neo4j.driver.internal.shaded.io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
at org.neo4j.driver.internal.shaded.io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.base/java.lang.Thread.run(Thread.java:832)
As I mention in my answer here, this exception comes from Neo4j Java Driver and there may be several reasons for this to happen.
For instance, this might happen when driver acquires a connection from internal connection pool that has been idle for too long. Some cloud providers limit connection idle time for load balancers. Driver may fail as soon as it tries using such connection.
You can enable connection liveness check to assist with this. It makes sure that a short network exchange happens for every connection that has been idle over the configured timeout. If exchange fails, another connection is picked or established before it is provided for further driver usage. While this involves an extra network exchange, it is likely to prevent driver failures that might lead to higher-level retry management with potentially exponential delay. The timeout can be set to zero if you wish to test every connection.
Sample configuration:
var config = Config.builder()
.withConnectionLivenessCheckTimeout( 60000, TimeUnit.MILLISECONDS )
.build();
var driver = GraphDatabase.driver( URL, AuthTokens, config );
This is the error I see
Only reported by one user, and they are using a qnap server and they have a large number of files to process so I guess this is the key factor. But could the problem be caused by something I am doing wrong with by database handling (using hibernate and h2) or is this more likely I am doing something wrong with general file handling ?
23/10/2019 14.48.43:EDT:WARNING: com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask#f1d393c -- 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 (10). Last acquisition attempt exception:
org.h2.jdbc.JdbcSQLNonTransientException: IO Exception: "java.io.IOException: No file descriptors available"; "/songkong/Prefs/Database/Database.mv.db" [90031-199]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:502)
at org.h2.message.DbException.getJdbcSQLException(DbException.java:427)
at org.h2.message.DbException.get(DbException.java:194)
at org.h2.message.DbException.convertIOException(DbException.java:392)
at org.h2.store.fs.FilePathDisk.toRealPath(FilePathDisk.java:220)
at org.h2.store.fs.FilePathDisk.toRealPath(FilePathDisk.java:35)
at org.h2.store.fs.FilePathWrapper.toRealPath(FilePathWrapper.java:118)
at org.h2.store.fs.FileUtils.toRealPath(FileUtils.java:78)
at org.h2.engine.ConnectionInfo.getName(ConnectionInfo.java:405)
at org.h2.engine.Engine.openSession(Engine.java:53)
at org.h2.engine.Engine.openSession(Engine.java:201)
at org.h2.engine.Engine.createSessionAndValidate(Engine.java:178)
at org.h2.engine.Engine.createSession(Engine.java:161)
at org.h2.engine.Engine.createSession(Engine.java:31)
at org.h2.engine.SessionRemote.connectEmbeddedOrServer(SessionRemote.java:336)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:169)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:148)
at org.h2.Driver.connect(Driver.java:69)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:146)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:195)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:184)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44)
at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648)
Caused by: java.io.IOException: No file descriptors available
at java.io.UnixFileSystem.canonicalize0(Native Method)
at java.io.UnixFileSystem.canonicalize(UnixFileSystem.java:172)
at java.io.File.getCanonicalPath(File.java:618)
at org.h2.store.fs.FilePathDisk.toRealPath(FilePathDisk.java:217)
... 22 more
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Connection Pool Exception: Cannot get a connection, pool error Timeout waiting for idle object
I am getting Cannot get a connection, pool error Timeout waiting for idle object error, When I try to create more than 250 threads in my web application. I am creating web application using JSF 2.0 and Hibernate.
I have tried with modified hibernate.xml,server.xml,context.xml and also mysql properties.
The followings are I am getting.
WARN (JDBCExceptionReporter.java:233) - SQL Error: 0, SQLState: null
ERROR (JDBCExceptionReporter.java:234) - Cannot get a connection, pool error Timeout waiting for idle object
ERROR (BaseServlet.java:301) - ******** java.lang.Thread.getStackTrace(Thread.java:1426)
Caused by: org.hibernate.exception.GenericJDBCException: Cannot open connection
org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:140)
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:128)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:160)
org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:81)
org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1473)
sun.reflect.GeneratedMethodAccessor378.invoke(Unknown Source)
Caused by: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object
org.apache.tomcat.dbcp.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:114)
org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
org.hibernate.connection.DatasourceConnectionProvider.getConnection(DatasourceConnectionProvider.java:92)
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:160)
org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:81)
org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1473)
sun.reflect.GeneratedMethodAccessor378.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
Caused by: java.util.NoSuchElementException: Timeout waiting for idle object
org.apache.tomcat.dbcp.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1144)
org.apache.tomcat.dbcp.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:106)
org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
org.hibernate.connection.DatasourceConnectionProvider.getConnection(DatasourceConnectionProvider.java:92)
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:160)
org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:81)
org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1473)
sun.reflect.GeneratedMethodAccessor378.invoke(Unknown Source)
Please if have any idea about this help me......
Maybe you have set a timeout for "dead" connections and some queries take longer than that. That means that your pool removed a busy connection as "dead" from the pool and requests another from the DB - until the DB pulls the plug.
To debug this, enable logging for your connection pool, so you can see when it requests new connections.
also check your mysql connection settings. and try to close connection when you are done with your db coz next time(beyond maxConnectionAge limit) that connection state will be dead .
I had such issue before, what you need to do is
close hibernate sessions when you are done with it.
e.g.
Session sess = factory.openSession();
Transaction tx;
try {
tx = sess.beginTransaction();
//do some work
...
tx.commit();
}
catch (Exception e) {
if (tx!=null) tx.rollback();
throw e;
}
finally {
sess.close(); // closing session
}
We are having hard time figuring out the properties defined, minIdle, maxIdle etc.
we are seeing the following error with the following setting
InitialSize=5
maxActive=50
maxIdle=40
maxWait=2000
Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:1001)
at org.springframework.jdbc.core.JdbcTemplate.call(JdbcTemplate.java:1064)
... 36 more
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object
at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:114)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
at org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource.getConnection(AbstractRoutingDataSource.java:148)
at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
... 39 more
Caused by: java.util.NoSuchElementException: Timeout waiting for idle object
at org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:1134)
at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java:106)
This is resolved. The issue was connection leak from the bad application code. The application code was written to access the underlying native connection to use Oracle Array Types and not managed properly. Changed the code to using SimpleNativeJdbcExtractor
http://static.springsource.org/spring/docs/2.0.x/api/org/springframework/jdbc/support/nativejdbc/SimpleNativeJdbcExtractor.html
Is there any way to determine database connection pool size (connection in used/connection remaining in connection pool) programmatically? We am using Hibernate with C3P0.
We are facing issues while connecting to db. Following exception is thrown and the data is not saved in db.
1005,MA,19/09/11 09:39:14,com.novosys.gtw.business.frontend.SnapshotMessageBusiness.save, Major: Cannot open connection
org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:126)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:114)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:142)
at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:85)
at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1354)
at sun.reflect.GeneratedMethodAccessor6.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:342)
at $Proxy0.beginTransaction(Unknown Source)
at com.novosys.gtw.util.base.BaseBusiness.save(BaseBusiness.java:199)
at com.novosys.gtw.business.backend.receivesnapshotmessage.filter.SaveMessageFilter.decode(SaveMessageFilter.java:102)
at org.apache.mina.filter.codec.demux.DemuxingProtocolCodecFactory$ProtocolDecoderImpl.doDecode(DemuxingProtocolCodecFactory.java:292)
at org.apache.mina.filter.codec.CumulativeProtocolDecoder.decode(CumulativeProtocolDecoder.java:133)
at org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecFilter.java:158)
at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(AbstractIoFilterChain.java:299)
at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilterChain.java:53)
at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceived(AbstractIoFilterChain.java:648)
at com.novosys.gtw.business.backend.receivesnapshotmessage.filter.WhitelistFilter.messageReceived(WhitelistFilter.java:231)
at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(AbstractIoFilterChain.java:299)
at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilterChain.java:53)
at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceived(AbstractIoFilterChain.java:648)
at com.novosys.gtw.business.backend.receivesnapshotmessage.filter.MoniterFilter.messageReceived(MoniterFilter.java:92)
at org.apache.mina.common.support.AbstractIoFilterChain.callNextMessageReceived(AbstractIoFilterChain.java:299)
at org.apache.mina.common.support.AbstractIoFilterChain.access$1100(AbstractIoFilterChain.java:53)
at org.apache.mina.common.support.AbstractIoFilterChain$EntryImpl$1.messageReceived(AbstractIoFilterChain.java:648)
at org.apache.mina.filter.executor.ExecutorFilter.processEvent(ExecutorFilter.java:220)
at org.apache.mina.filter.executor.ExecutorFilter$ProcessEventsRunnable.run(ExecutorFilter.java:264)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
at org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:51)
at java.lang.Thread.run(Thread.java:595)
Caused by: java.sql.SQLException: Connections could not be acquired from the underlying database!
at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:529)
at com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
at org.hibernate.connection.C3P0ConnectionProvider.getConnection(C3P0ConnectionProvider.java:78)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
... 31 more
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1319)
at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:557)
at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:477)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:525)
... 34 more
We tried to resolve it by increasing connection pool size and also increasing no. of connections available at MySQL level, but of no use. We are now trying to sort of debug it to see if its due to connection pool size or due to MySQL connection size. We want to log no. of connection available/in use in connection pool size but could not get any help from google.
Environment: Java, Hibernate, C3P0, MySQL
Session session = null;
Transaction transaction = null;
try {
session = HibernateUtil.getSessionFactory(datasource).getCurrentSession();
transaction = session.beginTransaction();
// db save called here
session.getTransaction().commit();
} catch (Exception e) {
Logger.write(LoggerConstant.MAJOR_ERROR, e.getMessage(), e, methodName);
} finally {
try {
if ((transaction != null) && (transaction.isActive())) {
transaction.rollback();
}
} catch (Exception e) {
Logger.write(LoggerConstant.CRITICAL_ERROR, e.getMessage(), e, methodName);
}
try {
if ((session != null) && (session.isOpen())) {
session.close();
}
} catch (Exception e) {
Logger.write(LoggerConstant.CRITICAL_ERROR, e.getMessage(), e, methodName);
}
}
I don't believe your problem is the connection pool, per se, but more generally a connection leak. This problem is commonly related to the use of HibernateDaoSupport.getSession() without properly pairing with HibernateDaoSupport.releaseSession(). In general, you want something like
public SomeObject getSomething()
{
Session session = null;
try
{
session = this.getSession();
Query query = session.createSQLQuery("SELECT * FROM SomeTable WHERE SomeClause").addEntity(SomeObject.class);
// extract object from query
return someObject;
}
finally
{
if (session != null)
this.releaseSession(session);
}
}
This can be automated by using a HibernateCallback. You do this by providing the query to this.getHibernateTemplate().executeFind which will use a session in Hibernate with automated resource management.
Apart from what ex0du5 has suggested, the exception trace also suggest following:
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1319)
This implies that the connection pool was not able to acquire new connection FROM DATABASE.
Please check the MySQL log for any errors.
Check the maximum connection pool size and max number of connection setting on mysql configuration. (Its least likely that connection pool size will be more that max connection on mysql configuration, but plz make sure of this)
Also there is a way where in you can monitor all the parameters (including max connection setting) of C3P0 conenction pool.
To properly configure the connection pool size, you need to have metrics to investigate the connection usage patterns.
FlexyPool aims to aid you figuring our the right connection pool size, because it can monitor the following metrics:
concurrent connections histogram
concurrent connection requests histogram
data source connection acquiring time histogram
connection lease time histogram
maximum pool size histogram
total connection acquiring time histogram
overflow pool size histogram
retries attempts histogram
You might check the following articles:
FlexyPool, reactive connection pooling
Professional Connection Pool Sizing
The simple scalability equation