我有一个运行Quartz 1.6.1w/持久性作业存储的应用程序，其中MySQL 5.1作为DB。这个应用程序过去可以在Tomcat6中启动。在某个时候，它开始在每次引导上抛出以下异常：

- MisfireHandler: Error handling misfires: Failure obtaining db row lock: Lock wait timeout exceeded; try restarting transaction
org.quartz.impl.jdbcjobstore.LockException: Failure obtaining db row lock: Lock wait timeout exceeded; try restarting transaction [See nested exception: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction]
    at org.quartz.impl.jdbcjobstore.StdRowLockSemaphore.executeSQL(StdRowLockSemaphore.java:112)
    at org.quartz.impl.jdbcjobstore.DBSemaphore.obtainLock(DBSemaphore.java:112)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport.doRecoverMisfires(JobStoreSupport.java:3075)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport$MisfireHandler.manage(JobStoreSupport.java:3838)
    at org.quartz.impl.jdbcjobstore.JobStoreSupport$MisfireHandler.run(JobStoreSupport.java:3858)
Caused by: java.sql.SQLException: Lock wait timeout exceeded; try restarting transaction
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3491)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3423)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1936)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2060)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2542)
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1734)
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1885)
    at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:76)
    at org.quartz.impl.jdbcjobstore.StdRowLockSemaphore.executeSQL(StdRowLockSemaphore.java:92)
    ... 4 more

我应该提到，这个应用程序还使用JPA /Hibernate，使用C3P0作为数据源连接池。此异常总是在JPA完成更新我的架构后直接抛出。

首先，我升级到Quartz 1.6.5，异常消失了，但是应用程序似乎被冻结了。日志中的最后一件事--过去的例外情况--是：

...hbm2ddl stuff...
2969 [Thread-1] INFO org.hibernate.tool.hbm2ddl.SchemaUpdate - schema update complete
- Handling 6 trigger(s) that missed their scheduled fire-time.

之后什么都没有出现，而and应用程序也没有为请求提供服务；它们只是无限期地挂起。

当我在异常后运行具有显示INNODB状态的 mysql 命令行客户端时，它始终显示两个可疑的事务：

----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 49, signal count 49
Mutex spin waits 0, rounds 2100, OS waits 0
RW-shared spins 115, OS waits 49; RW-excl spins 0, OS waits 0
------------
TRANSACTIONS
------------
Trx id counter 0 165688
Purge done for trx's n:o < 0 165685 undo n:o < 0 0
History list length 12
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0 0, not started, OS thread id 5012
MySQL thread id 8, query id 1798 localhost 127.0.0.1 root
SHOW INNODB STATUS