Question

我正在使用HIkariCP，Hibernate和MySQL。问题是：当应用程序启动时，一切正常。但是当我让它闲置一段时间然后回来试图从Hikari获得连接时，它会引发异常：

Caused by: java.sql.SQLTransientConnectionException: Main DB Pool - Connection is not available, request timed out after 60072ms.
    at com.zaxxer.hikari.pool.HikariPool.createTimeoutException(HikariPool.java:548)
    at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:186)
    at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:145)
    at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:83)
    at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122)
    at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:35)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:115)
    ... 59 common frames omitted
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 820 887 milliseconds ago.  The last packet sent successfully to the server was 60 060 milliseconds ago.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:989)
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3559)
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3459)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3900)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2527)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2680)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2486)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2444)
    at com.mysql.jdbc.StatementImpl.executeInternal(StatementImpl.java:845)
    at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:745)
    at com.zaxxer.hikari.pool.PoolBase.isConnectionAlive(PoolBase.java:157)
    at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:169)
    ... 64 common frames omitted
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
    at java.net.SocketInputStream.read(SocketInputStream.java:170)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:101)
    at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:144)
    at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:174)
    at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3008)
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3469)
    ... 74 common frames omitted

MySQL数据库位于外部服务器，它有一些超时/会话过期功能，我无法更改它。我认为问题是由于某种会话到期而导致的，因为非活动时间太长（因为问题仅在应用程序保持空闲一段时间后才会发生）。可能是类似的问题，我不知道连接丢失的确切原因是什么。

问题是：如何强制Hikari在这种情况下刷新连接而不是抛出异常？（或问题可能在哪里？）

我的配置：

    HikariConfig config = new HikariConfig();

    config.setPoolName("Main DB Pool");
    config.addDataSourceProperty("url", "jdbc:mysql://" + host);

    config.setUsername(user);
    config.setPassword(password);
    config.setDataSourceClassName(dataSourceClass);
    config.setMaximumPoolSize(maxPoolSize);
    config.setIdleTimeout(30000);
    config.setConnectionTimeout(60000);
    config.setValidationTimeout(60000);
    config.setConnectionInitSql("SELECT 1");
    config.setConnectionTestQuery("SELECT 1");
    config.setLeakDetectionThreshold(120000);

    return new HikariDataSource(config);

Answer 1

来自文档。您需要弄清楚外部服务器超时是什么，并将HikariCP配置为更短。

⌚maxLifetime 此属性控制池中连接的最长生命周期。使用中的连接永远不会退役，只有当它关闭时才会被删除。 我们强烈建议您设置此值，并且应该比任何数据库或基础架构施加的连接时间限制至少少30秒。值0表示没有最大生命周期（无限生命周期），当然主题是idleTimeout设置。默认值：1800000（30分钟）

空闲一段时间后，HikariCP正在失去与MySQL的连接

1 个答案: