I hava on topic with a lot of producers and 1 durable subscribe consumer. activemq conneted to mysql with c3p0 datasoure pool with the default configuration. The jdbcPersistenceAdapter cleanupPeriod is 3000。 when all producers commit message, sometimes activemq blocked, no message can send or received,even all produces are shutdown. going into stack all produces bocked:
and a clean thead blocked Thread 18234: (state = BLOCKED) - java.lang.Object.wait(long) @bci=0 (Compiled frame; information may be imprecise) - com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(long) @bci=171, line=1315 (Compiled frame) - com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(long) @bci=231, line=557 (Compiled frame) - com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(long) @bci=2, line=477 (Compiled frame) - com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection() @bci=9, line=525 (Compiled frame) - com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection() @bci=7, line=128 (Compiled frame) - org.apache.activemq.store.jdbc.TransactionContext.getConnection() @bci=12, line=58 (Compiled frame) - org.apache.activemq.store.jdbc.adapter.DefaultJDBCAdapter.doDeleteOldMessages(org.apache.activemq.store.jdbc.TransactionContext) @bci=50, line=824 (Compiled frame) - org.apache.activemq.store.jdbc.JDBCPersistenceAdapter.cleanup() @bci=22, line=345 (Compiled frame) </hraw> Look into the souce code, I find producer submit step : begin transaction(get a connection) --> insert/delete every message before get a cleanupExclusiveLock read lock ---> release read lock --> commit ---> close connection; cleanup task step : get cleanupExclusiveLock write lock---> get a datasouce connection ---> delete expired topic messages --> commit --> release write lock; Produces get all the connections of the pool and waiting for the clearup task release write lock, while the clearup task got the write lock waiting for a connection. is it a dead lock? why the clear up thread get a datasouce connection first? -- View this message in context: http://activemq.2283324.n4.nabble.com/Dead-Lock-Useing-Jdbc-database-store-in-transaction-mode-tp4675247.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.
