限制jdbc连接池固定数量

Question

您好，我将 micronaut 数据与各种 jdbc 连接池一起使用。我第一次吃了 hikari，也尝试了 tomcat 一个。

我假设将数据源设置为 maximum-pool-size: 10 会导致最多 10 个打开的连接。但似乎有很多打开和关闭正在进行。再加上同时有很多o个请求，它使用的连接远远不止只有10个。问题是，azure postgresql 总共只允许 100 个连接。

目前我有运行 7 个应用程序访问该数据库。我预计最多会产生 70 个连接。但实际上远不止于此。

我也试过使用 tomcat jdbc 池，他的行为有点不同。而且还使用了 10 个以上的连接。我还使用 java 探查器进行了检查，发现有时每秒最多有 100 个 open/close 连接事件。

关于在这种情况下如何操作的任何建议，除了使用第二个数据库。我希望池能够缓冲调用，特别是因为它们来自 kafka 主题。不过好吧，好像不一样了。

--- 编辑添加 hikari 日志

这里是hikari的日志输出

2020-12-11 11:59:40,983 [main] DEBUG com.zaxxer.hikari.HikariConfig - Driver class org.postgresql.Driver found in Thread context class loader jdk.internal.loader.ClassLoaders$AppClassLoader@2c13da15
2020-12-11 11:59:40,993 [main] DEBUG com.zaxxer.hikari.HikariConfig - HikariPool-1 - configuration:
2020-12-11 11:59:40,999 [main] DEBUG com.zaxxer.hikari.HikariConfig - allowPoolSuspension.............false
2020-12-11 11:59:41,000 [main] DEBUG com.zaxxer.hikari.HikariConfig - autoCommit......................true
2020-12-11 11:59:41,000 [main] DEBUG com.zaxxer.hikari.HikariConfig - catalog.........................none
2020-12-11 11:59:41,001 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionInitSql...............none
2020-12-11 11:59:41,001 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTestQuery............."SELECT 1;"
2020-12-11 11:59:41,001 [main] DEBUG com.zaxxer.hikari.HikariConfig - connectionTimeout...............30000
2020-12-11 11:59:41,002 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSource......................none
2020-12-11 11:59:41,002 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceClassName.............none
2020-12-11 11:59:41,002 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceJNDI..................none
2020-12-11 11:59:41,003 [main] DEBUG com.zaxxer.hikari.HikariConfig - dataSourceProperties............{password=<masked>}
2020-12-11 11:59:41,004 [main] DEBUG com.zaxxer.hikari.HikariConfig - driverClassName................."org.postgresql.Driver"
2020-12-11 11:59:41,004 [main] DEBUG com.zaxxer.hikari.HikariConfig - exceptionOverrideClassName......none
2020-12-11 11:59:41,004 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckProperties...........{}
2020-12-11 11:59:41,005 [main] DEBUG com.zaxxer.hikari.HikariConfig - healthCheckRegistry.............none
2020-12-11 11:59:41,005 [main] DEBUG com.zaxxer.hikari.HikariConfig - idleTimeout.....................600000
2020-12-11 11:59:41,005 [main] DEBUG com.zaxxer.hikari.HikariConfig - initializationFailTimeout.......1
2020-12-11 11:59:41,006 [main] DEBUG com.zaxxer.hikari.HikariConfig - isolateInternalQueries..........false
2020-12-11 11:59:41,007 [main] DEBUG com.zaxxer.hikari.HikariConfig - jdbcUrl.........................jdbc:postgresql://URL:5432/postgres
2020-12-11 11:59:41,007 [main] DEBUG com.zaxxer.hikari.HikariConfig - leakDetectionThreshold..........0
2020-12-11 11:59:41,007 [main] DEBUG com.zaxxer.hikari.HikariConfig - maxLifetime.....................1800000
2020-12-11 11:59:41,008 [main] DEBUG com.zaxxer.hikari.HikariConfig - maximumPoolSize.................10
2020-12-11 11:59:41,008 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricRegistry..................none
2020-12-11 11:59:41,008 [main] DEBUG com.zaxxer.hikari.HikariConfig - metricsTrackerFactory...........none
2020-12-11 11:59:41,009 [main] DEBUG com.zaxxer.hikari.HikariConfig - minimumIdle.....................10
2020-12-11 11:59:41,009 [main] DEBUG com.zaxxer.hikari.HikariConfig - password........................<masked>
2020-12-11 11:59:41,009 [main] DEBUG com.zaxxer.hikari.HikariConfig - poolName........................"HikariPool-1"
2020-12-11 11:59:41,010 [main] DEBUG com.zaxxer.hikari.HikariConfig - readOnly........................false
2020-12-11 11:59:41,010 [main] DEBUG com.zaxxer.hikari.HikariConfig - registerMbeans..................false
2020-12-11 11:59:41,011 [main] DEBUG com.zaxxer.hikari.HikariConfig - scheduledExecutor...............none
2020-12-11 11:59:41,011 [main] DEBUG com.zaxxer.hikari.HikariConfig - schema.........................."SCHEMA"
2020-12-11 11:59:41,011 [main] DEBUG com.zaxxer.hikari.HikariConfig - threadFactory...................internal
2020-12-11 11:59:41,011 [main] DEBUG com.zaxxer.hikari.HikariConfig - transactionIsolation............default
2020-12-11 11:59:41,012 [main] DEBUG com.zaxxer.hikari.HikariConfig - username........................"USERNAME"
2020-12-11 11:59:41,012 [main] DEBUG com.zaxxer.hikari.HikariConfig - validationTimeout...............5000

Answer 1

我发现了错误 - 或者至少解决了问题。

在将一些数据保存到数据库中的同时，我还尝试更新缓存。但是由于咖啡因加载缓存的变化，每次保存也会导致获取完全相同的数据对象实例。

我的猜测是由于交易引起的麻烦。用 cache.replace 替换 cache.get 后一切正常。

限制jdbc连接池固定数量

Limit jdbc connection pool fixed amount

jdbc

hikaricp

tomcat-jdbc

micronaut

micronaut-data