Spring Boot 2.1.2。
2个环境：local（postgres 11）和qa（带有postgres 10和应用程序的docker群）
maxLifetime通过之后，hikari会重新创建连接（关闭旧的连接并创建新的连接），但是在qa上，环境连接并未关闭：使用select * from pg_stat_activity wheredataname=...检查
在日志中，我们有：
2019-09-25 12:00:20.694 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@54d41592: (connection has passed maxLifetime)
2019-09-25 12:00:20.699 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@29e14ddb
2019-09-25 12:00:26.372 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@11684c62: (connection has passed maxLifetime)
2019-09-25 12:00:26.376 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@453f8d6c
2019-09-25 12:00:28.130 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@1b2ef2bc: (connection has passed maxLifetime)
2019-09-25 12:00:28.135 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@4bf86bbb
2019-09-25 12:00:28.459 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@34fbeadd: (connection has passed maxLifetime)
2019-09-25 12:00:28.464 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@4fc7e61c
2019-09-25 12:00:31.962 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@40771fc4: (connection has passed maxLifetime)
2019-09-25 12:00:31.966 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@ac56180
2019-09-25 12:00:35.600 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@65cae248: (connection has passed maxLifetime)
2019-09-25 12:00:35.607 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@33a8d959
2019-09-25 12:00:35.649 WARN 6 --- [ scheduling-1] c.z.h.p.PoolBase : HikariPool-1 - Failed to validate connection org.postgresql.jdbc.PgConnection@15e91fa9 (This connection has been closed.). Possibly consider using a shorter maxLifetime value.
2019-09-25 12:00:35.650 WARN 6 --- [ scheduling-1] c.z.h.p.PoolBase : HikariPool-1 - Failed to validate connection org.postgresql.jdbc.PgConnection@11d699cc (This connection has been closed.). Possibly consider using a shorter maxLifetime value.
2019-09-25 12:00:35.651 WARN 6 --- [ scheduling-1] c.z.h.p.PoolBase : HikariPool-1 - Failed to validate connection org.postgresql.jdbc.PgConnection@3883b6a6 (This connection has been closed.). Possibly consider using a shorter maxLifetime value.
2019-09-25 12:00:35.652 WARN 6 --- [ scheduling-1] c.z.h.p.PoolBase : HikariPool-1 - Failed to validate connection org.postgresql.jdbc.PgConnection@230234a5 (This connection has been closed.). Possibly consider using a shorter maxLifetime value.
2019-09-25 12:00:35.657 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@15e91fa9: (connection is dead)
2019-09-25 12:00:35.657 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@11d699cc: (connection is dead)
2019-09-25 12:00:35.657 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@3883b6a6: (connection is dead)
2019-09-25 12:00:35.658 DEBUG 6 --- [nnection closer] c.z.h.p.PoolBase : HikariPool-1 - Closing connection org.postgresql.jdbc.PgConnection@230234a5: (connection is dead)
2019-09-25 12:00:35.674 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@3b85c924
2019-09-25 12:00:35.678 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@4b022f4e
2019-09-25 12:00:35.686 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@6aea9ecf
2019-09-25 12:00:35.691 DEBUG 6 --- [onnection adder] c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@1ffdf0da
为什么连接没有关闭？
编辑： Hikari配置：
c.z.h.HikariConfig : HikariPool-1 - configuration:
c.z.h.HikariConfig : allowPoolSuspension.............false
c.z.h.HikariConfig : autoCommit......................true
c.z.h.HikariConfig : catalog.........................none
c.z.h.HikariConfig : connectionInitSql...............none
c.z.h.HikariConfig : connectionTestQuery.............none
c.z.h.HikariConfig : connectionTimeout...............30000
c.z.h.HikariConfig : dataSource......................none
c.z.h.HikariConfig : dataSourceClassName.............none
c.z.h.HikariConfig : dataSourceJNDI..................none
c.z.h.HikariConfig : dataSourceProperties............{password=<masked>}
c.z.h.HikariConfig : driverClassName................."org.postgresql.Driver"
c.z.h.HikariConfig : healthCheckProperties...........{}
c.z.h.HikariConfig : healthCheckRegistry.............none
c.z.h.HikariConfig : idleTimeout.....................600000
c.z.h.HikariConfig : initializationFailTimeout.......1
c.z.h.HikariConfig : isolateInternalQueries..........false
c.z.h.HikariConfig : jdbcUrl.........................jdbc:postgresql://postgres/db
c.z.h.HikariConfig : leakDetectionThreshold..........0
c.z.h.HikariConfig : maxLifetime.....................1800000
c.z.h.HikariConfig : maximumPoolSize.................10
c.z.h.HikariConfig : metricRegistry..................none
c.z.h.HikariConfig : metricsTrackerFactory...........none
c.z.h.HikariConfig : minimumIdle.....................10
c.z.h.HikariConfig : password........................<masked>
c.z.h.HikariConfig : poolName........................"HikariPool-1"
c.z.h.HikariConfig : readOnly........................false
c.z.h.HikariConfig : registerMbeans..................false
c.z.h.HikariConfig : scheduledExecutor...............none
c.z.h.HikariConfig : schema..........................none
c.z.h.HikariConfig : threadFactory...................internal
c.z.h.HikariConfig : transactionIsolation............default
c.z.h.HikariConfig : username........................"username"
c.z.h.HikariConfig : validationTimeout...............5000
c.z.h.HikariDataSource : HikariPool-1 - Starting...
c.z.h.p.HikariPool : HikariPool-1 - Added connection org.postgresql.jdbc.PgConnection@53fd0d10
c.z.h.HikariDataSource : HikariPool-1 - Start completed.
o.f.c.i.d.DatabaseFactory : Database: jdbc:postgresql://postgres/db (PostgreSQL 10.10)
答案 0 :(得分：0)
通过将maxLifetime设置为10分钟来解决。
说明： 事实证明，docker swarm会以某种方式丢弃空闲连接。因此，当hikari关闭连接时，没有任何东西到达postgres，因此从postgres的角度来看，仍然存在连接。比默认的Docker空闲连接超时少10分钟，因此连接已正确关闭。