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https://issues.apache.org/jira/browse/QPID-8080?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16328794#comment-16328794
]
Keith Wall edited comment on QPID-8080 at 1/17/18 1:58 PM:
-----------------------------------------------------------
This problem will manifest in a number of places: recovery dequeuing a large
number of messages, large number of async acks arriving on the wire in one go.
The code currently allocates a JDBC connection for each
AsyncAutoCommitTransaction
({{org/apache/qpid/server/txn/AsyncAutoCommitTransaction.java:104}}). This
connection remains open until the
{{org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore#_executor}}
completes the commit and closes the connection. The problem will arise if the
number of jobs queued up on the executor exceeds the maximum number of open
connections allowable by the database. This a race between the executor
committing and closing connections and the arrival of new async auto commit
jobs.
If the user adds BoneCP, this reduces the chances of the problem occurring but
does not eliminate it. If the BoneCP hits its maximum number of open
connections the attempt to get the next connection will block. This will block
Broker-J's IO thread. BoneCP keeps retrying up to 5 * 7000 milliseconds before
giving up. If is gives up a connection exception will result and Qpid will
fail. If a connection is released in time, the blocked thread will get a
connection and the problem won't manifest. Currently it is not possible to tune
{{acquireRetryDelay}} or {{acquireRetryAttempts}} from Qpid.
To me it seems odd that each {{AsyncAutoCommitTransaction}} requires private
use of a connection. We never need to be able to rollback the the work of a
AsyncAutoCommitTransaction so the transaction isolation is needless. We ought
to be using JDBC in a transactional less mode for this work.
LocalTransactiions on the other hand would continue to require an underlying
JDBC transaction.
was (Author: k-wall):
This problem will manifest in a number of places: recovery dequeuing a large
number of messages, large number of async acks arriving on the wire in one go.
The code currently allocates a JDBC connection for each
AsyncAutoCommitTransaction
({{org/apache/qpid/server/txn/AsyncAutoCommitTransaction.java:104}}). This
connection remains open until the
{{org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore#_executor}}
completes the commit and closes the connection. The problem will arise if the
number of jobs queued up on the executed exceeds the maximum number of open
connections allowable by the database. This a race between the executor
committing and closing connections and the arrival of new async auto commit
jobs.
If the user adds BoneCP, this reduces the chances of the problem occurring but
does not eliminate it. If the BoneCP hits its maximum number of open
connections the attempt to get the next connection will block. This will block
Broker-J's IO thread. BoneCP keeps retrying up to 5 * 7000 milliseconds before
giving up. If is gives up a connection exception will result and Qpid will
fail. If a connection is released in time, the blocked thread will get a
connection and the problem won't manifest. Currently it is not possible to tune
{{acquireRetryDelay}} or {{acquireRetryAttempts}} from Qpid.
To me it seems odd that each {{AsyncAutoCommitTransaction}} requires private
use of a connection. We never need to be able to rollback the the work of a
AsyncAutoCommitTransaction so the transaction isolation is needless. We ought
to be using JDBC in a transactional less mode for this work.
LocalTransactiions on the other hand would continue to require an underlying
JDBC transaction.
> [Broker-J] Broker can crash when JDBC message store opens to many SQL
> connections to the RDBMS exceeding the maximum connection limit
> -------------------------------------------------------------------------------------------------------------------------------------
>
> Key: QPID-8080
> URL: https://issues.apache.org/jira/browse/QPID-8080
> Project: Qpid
> Issue Type: Bug
> Components: Broker-J
> Affects Versions: qpid-java-6.0.8, qpid-java-broker-7.0.0, qpid-java-6.1.5
> Environment: Broker-J with JDVC message store can crash when
> messaging client(s) consume or publish small messages in non-transactional
> manner (for example, when AUTO_ACK acknowledge mode is used by JMS client).
> The broker creates \{{AsyncAutoCommitTransaction}} per each
> consumed/published message. Each transaction opens a separate connection to
> RDBMS server. The number of concurrent \{{AsyncAutoCommitTransaction}} can
> exceed the maximum connection limit. As result, sql connection establishment
> fails causing broker to crash with the stack trace like the one below:
> {noformat}
> ########################################################################
> #
> # Unhandled Exception
> org.apache.qpid.server.util.ServerScopedRuntimeException:
> org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections in Thread
> IO-/127.0.0.1:55228
> #
> # Exiting
> #
> ########################################################################
> org.apache.qpid.server.util.ServerScopedRuntimeException:
> org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.lambda$received$1(AMQPConnection_0_10Impl.java:157)
> at java.security.AccessController.doPrivileged(Native Method)
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.received(AMQPConnection_0_10Impl.java:141)
> at
> org.apache.qpid.server.transport.MultiVersionProtocolEngine.received(MultiVersionProtocolEngine.java:134)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.processAmqpData(NonBlockingConnection.java:610)
> at
> org.apache.qpid.server.transport.NonBlockingConnectionPlainDelegate.processData(NonBlockingConnectionPlainDelegate.java:58)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.doRead(NonBlockingConnection.java:496)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.doWork(NonBlockingConnection.java:270)
> at
> org.apache.qpid.server.transport.NetworkConnectionScheduler.processConnection(NetworkConnectionScheduler.java:134)
> at
> org.apache.qpid.server.transport.SelectorThread$ConnectionProcessor.processConnection(SelectorThread.java:575)
> at
> org.apache.qpid.server.transport.SelectorThread$SelectionTask.performSelect(SelectorThread.java:366)
> at
> org.apache.qpid.server.transport.SelectorThread$SelectionTask.run(SelectorThread.java:97)
> at
> org.apache.qpid.server.transport.SelectorThread.run(SelectorThread.java:533)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> at
> org.apache.qpid.server.bytebuffer.QpidByteBufferFactory.lambda$null$0(QpidByteBufferFactory.java:464)
> at java.lang.Thread.run(Thread.java:745)
> Caused by: org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore$JDBCTransaction.<init>(AbstractJDBCMessageStore.java:1065)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore$RecordedJDBCTransaction.<init>(GenericAbstractJDBCMessageStore.java:122)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore$RecordedJDBCTransaction.<init>(GenericAbstractJDBCMessageStore.java:118)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore.newTransaction(GenericAbstractJDBCMessageStore.java:114)
> at
> org.apache.qpid.server.txn.AsyncAutoCommitTransaction.dequeue(AsyncAutoCommitTransaction.java:104)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.acknowledge(ServerSession.java:1185)
> at
> org.apache.qpid.server.protocol.v0_10.ConsumerTarget_0_10.acknowledge(ConsumerTarget_0_10.java:401)
> at
> org.apache.qpid.server.protocol.v0_10.ExplicitAcceptDispositionChangeListener.onAccept(ExplicitAcceptDispositionChangeListener.java:51)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession$2.performAction(ServerSession.java:1000)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.dispositionChange(ServerSession.java:1091)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.accept(ServerSession.java:995)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.messageAccept(ServerSessionDelegate.java:142)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.messageAccept(ServerSessionDelegate.java:91)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MessageAccept.dispatch(MessageAccept.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:1832)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:108)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:91)
> at
> org.apache.qpid.server.protocol.v0_10.transport.Method.delegate(Method.java:153)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.received(ServerSession.java:508)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnection.dispatch(ServerConnection.java:539)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.handle(ServerConnectionDelegate.java:115)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.handle(ServerConnectionDelegate.java:52)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MethodDelegate.messageAccept(MethodDelegate.java:117)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MessageAccept.dispatch(MessageAccept.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.command(ServerConnectionDelegate.java:103)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.command(ServerConnectionDelegate.java:52)
> at
> org.apache.qpid.server.protocol.v0_10.transport.Method.delegate(Method.java:153)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnection.received(ServerConnection.java:279)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.emit(ServerAssembler.java:178)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.assemble(ServerAssembler.java:271)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.frame(ServerAssembler.java:205)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.received(ServerAssembler.java:135)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.lambda$received$0(ServerAssembler.java:96)
> at java.security.AccessController.doPrivileged(Native Method)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.received(ServerAssembler.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerInputHandler.received(ServerInputHandler.java:184)
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.lambda$received$1(AMQPConnection_0_10Impl.java:146)
> ... 16 more
> Caused by: java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.get(ExceptionMapper.java:175)
> at
> org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.getException(ExceptionMapper.java:110)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connectWithoutProxy(AbstractConnectProtocol.java:1088)
> at org.mariadb.jdbc.internal.util.Utils.retrieveProxy(Utils.java:493)
> at
> org.mariadb.jdbc.MariaDbConnection.newConnection(MariaDbConnection.java:150)
> at org.mariadb.jdbc.Driver.connect(Driver.java:86)
> at java.sql.DriverManager.getConnection(DriverManager.java:664)
> at java.sql.DriverManager.getConnection(DriverManager.java:247)
> at
> org.apache.qpid.server.store.jdbc.DefaultConnectionProvider.getConnection(DefaultConnectionProvider.java:49)
> at
> org.apache.qpid.server.store.jdbc.GenericJDBCMessageStore.getConnection(GenericJDBCMessageStore.java:127)
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore.newConnection(AbstractJDBCMessageStore.java:497)
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore$JDBCTransaction.<init>(AbstractJDBCMessageStore.java:1061)
> ... 52 more
> Caused by: java.sql.SQLException: Too many connections
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.authentication(AbstractConnectProtocol.java:849)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.handleConnectionPhases(AbstractConnectProtocol.java:775)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connect(AbstractConnectProtocol.java:453)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connectWithoutProxy(AbstractConnectProtocol.java:1084)
> ... 61 more
> Process finished with exit code 1
> {noformat}
>
> Only JDBC message stores with default connection provider (no pool) are
> affected by the issue. It can be work around by using connection pool, for
> example, BoneCP.
> Reporter: Alex Rudyy
> Priority: Major
>
> Broker-J can crash when JDBC message store is configured with a connection
> pool NONE and a number of SQL connections created by the message store
> exceeds the RDBMS maximum connection limit. For example, this can happen when
> JMS client simply consumes or publishes messages using {{AUTO_ACKNOWLEDGE}}
> sessions and a number of in-progress published or consumed messages exceeds
> the RDBMS maximum connection limit. The underlying broker
> {{ServerTransaction}} implementations open a new SQL connection on
> transaction creation. The SQL connection is closed when transaction is
> committed or rollback. As result, the number of concurrent
> {{ServerTransaction}} s is limited by RDBMS maximum connection limit. On
> exceeding the limit broker crashes with the stack trace like the one below:
> {noformat}
> ########################################################################
> #
> # Unhandled Exception
> org.apache.qpid.server.util.ServerScopedRuntimeException:
> org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections in Thread
> IO-/127.0.0.1:55228
> #
> # Exiting
> #
> ########################################################################
> org.apache.qpid.server.util.ServerScopedRuntimeException:
> org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.lambda$received$1(AMQPConnection_0_10Impl.java:157)
> at java.security.AccessController.doPrivileged(Native Method)
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.received(AMQPConnection_0_10Impl.java:141)
> at
> org.apache.qpid.server.transport.MultiVersionProtocolEngine.received(MultiVersionProtocolEngine.java:134)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.processAmqpData(NonBlockingConnection.java:610)
> at
> org.apache.qpid.server.transport.NonBlockingConnectionPlainDelegate.processData(NonBlockingConnectionPlainDelegate.java:58)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.doRead(NonBlockingConnection.java:496)
> at
> org.apache.qpid.server.transport.NonBlockingConnection.doWork(NonBlockingConnection.java:270)
> at
> org.apache.qpid.server.transport.NetworkConnectionScheduler.processConnection(NetworkConnectionScheduler.java:134)
> at
> org.apache.qpid.server.transport.SelectorThread$ConnectionProcessor.processConnection(SelectorThread.java:575)
> at
> org.apache.qpid.server.transport.SelectorThread$SelectionTask.performSelect(SelectorThread.java:366)
> at
> org.apache.qpid.server.transport.SelectorThread$SelectionTask.run(SelectorThread.java:97)
> at
> org.apache.qpid.server.transport.SelectorThread.run(SelectorThread.java:533)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
> at
> org.apache.qpid.server.bytebuffer.QpidByteBufferFactory.lambda$null$0(QpidByteBufferFactory.java:464)
> at java.lang.Thread.run(Thread.java:745)
> Caused by: org.apache.qpid.server.store.StoreException:
> java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore$JDBCTransaction.<init>(AbstractJDBCMessageStore.java:1065)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore$RecordedJDBCTransaction.<init>(GenericAbstractJDBCMessageStore.java:122)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore$RecordedJDBCTransaction.<init>(GenericAbstractJDBCMessageStore.java:118)
> at
> org.apache.qpid.server.store.jdbc.GenericAbstractJDBCMessageStore.newTransaction(GenericAbstractJDBCMessageStore.java:114)
> at
> org.apache.qpid.server.txn.AsyncAutoCommitTransaction.dequeue(AsyncAutoCommitTransaction.java:104)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.acknowledge(ServerSession.java:1185)
> at
> org.apache.qpid.server.protocol.v0_10.ConsumerTarget_0_10.acknowledge(ConsumerTarget_0_10.java:401)
> at
> org.apache.qpid.server.protocol.v0_10.ExplicitAcceptDispositionChangeListener.onAccept(ExplicitAcceptDispositionChangeListener.java:51)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession$2.performAction(ServerSession.java:1000)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.dispositionChange(ServerSession.java:1091)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.accept(ServerSession.java:995)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.messageAccept(ServerSessionDelegate.java:142)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.messageAccept(ServerSessionDelegate.java:91)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MessageAccept.dispatch(MessageAccept.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:1832)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:108)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSessionDelegate.command(ServerSessionDelegate.java:91)
> at
> org.apache.qpid.server.protocol.v0_10.transport.Method.delegate(Method.java:153)
> at
> org.apache.qpid.server.protocol.v0_10.ServerSession.received(ServerSession.java:508)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnection.dispatch(ServerConnection.java:539)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.handle(ServerConnectionDelegate.java:115)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.handle(ServerConnectionDelegate.java:52)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MethodDelegate.messageAccept(MethodDelegate.java:117)
> at
> org.apache.qpid.server.protocol.v0_10.transport.MessageAccept.dispatch(MessageAccept.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.command(ServerConnectionDelegate.java:103)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnectionDelegate.command(ServerConnectionDelegate.java:52)
> at
> org.apache.qpid.server.protocol.v0_10.transport.Method.delegate(Method.java:153)
> at
> org.apache.qpid.server.protocol.v0_10.ServerConnection.received(ServerConnection.java:279)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.emit(ServerAssembler.java:178)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.assemble(ServerAssembler.java:271)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.frame(ServerAssembler.java:205)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.received(ServerAssembler.java:135)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.lambda$received$0(ServerAssembler.java:96)
> at java.security.AccessController.doPrivileged(Native Method)
> at
> org.apache.qpid.server.protocol.v0_10.ServerAssembler.received(ServerAssembler.java:90)
> at
> org.apache.qpid.server.protocol.v0_10.ServerInputHandler.received(ServerInputHandler.java:184)
> at
> org.apache.qpid.server.protocol.v0_10.AMQPConnection_0_10Impl.lambda$received$1(AMQPConnection_0_10Impl.java:146)
> ... 16 more
> Caused by: java.sql.SQLNonTransientConnectionException: Too many connections
> at
> org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.get(ExceptionMapper.java:175)
> at
> org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.getException(ExceptionMapper.java:110)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connectWithoutProxy(AbstractConnectProtocol.java:1088)
> at org.mariadb.jdbc.internal.util.Utils.retrieveProxy(Utils.java:493)
> at
> org.mariadb.jdbc.MariaDbConnection.newConnection(MariaDbConnection.java:150)
> at org.mariadb.jdbc.Driver.connect(Driver.java:86)
> at java.sql.DriverManager.getConnection(DriverManager.java:664)
> at java.sql.DriverManager.getConnection(DriverManager.java:247)
> at
> org.apache.qpid.server.store.jdbc.DefaultConnectionProvider.getConnection(DefaultConnectionProvider.java:49)
> at
> org.apache.qpid.server.store.jdbc.GenericJDBCMessageStore.getConnection(GenericJDBCMessageStore.java:127)
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore.newConnection(AbstractJDBCMessageStore.java:497)
> at
> org.apache.qpid.server.store.jdbc.AbstractJDBCMessageStore$JDBCTransaction.<init>(AbstractJDBCMessageStore.java:1061)
> ... 52 more
> Caused by: java.sql.SQLException: Too many connections
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.authentication(AbstractConnectProtocol.java:849)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.handleConnectionPhases(AbstractConnectProtocol.java:775)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connect(AbstractConnectProtocol.java:453)
> at
> org.mariadb.jdbc.internal.protocol.AbstractConnectProtocol.connectWithoutProxy(AbstractConnectProtocol.java:1084)
> ... 61 more
> Process finished with exit code 1
> {noformat}
> Only JDBC message stores with connection pool NONE are affected by the issue.
> It can be worked around by using a connection pool, for example BONECP, which
> is provided by the broker.
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