As we all know, the springboot2 project uses HikariCP connection pooling, which is the “fastest connection pooling ever”. After the springBoot2 project system went online, a warning was found in the log:
WARN com.zaxxer.hikari.pool.PoolBase - Retail_HikariCP - Failed to validate connection com.mysql.jdbc.JDBC4Connection@355cd37b (No operations allowed after connection closed.). Possibly consider using a shorter maxLifetime value.
Copy the codeThe warning is that the maxLifetime value is recommended to be set to a smaller value. This indicates that there is a problem with the configuration file. Some brief configuration instructions for the HikariCP connection pool are as follows:
| Configuration items | describe | Constructor default value |
|---|---|---|
| connectionTimeout | The maximum number of milliseconds to wait for connections from the pool | 30000 |
| idleTimeout | The maximum amount of time a connection is allowed to remain idle in the pool | 600000 |
| maxLifetime | Maximum connection lifetime in the pool | 1800000 |
Change the maxLifetime value from 1800000 to 600000 as prompted, which is the same as idle-timeout.
# # database configuration spring. The datasource. Type = com. Zaxxer. Hikari. HikariDataSource spring. The datasource. DriverClassName = com.mysql.jdbc.Driver spring.datasource.u```rl = jdbc:mysql://localhost:3306/ssm? useUnicode=true&characterEncoding=utf-8&useSSL=false spring.datasource.username = root spring.datasource.password = root ## Hikari connection pool configuration ------ https://github.com/brettwooldridge/HikariCP # # minimum number of idle connections spring. The datasource. Hikari. Minimum - idle = 5 # # free connection for most time, The default 600000 (10 minutes) spring. The datasource. Hikari. Idle - timeout = 600000 # # connection pool maximum number of connections, Default is 10. Spring datasource. Hikari. Maximum - the pool - size = 10 # # this property control back from a pool of connections the default autocommit behaviour, default: True spring. The datasource. Hikari. Auto - commit = true # # connection pool and spring. The datasource. Hikari. The pool - name = testHikariCP # # This property control connections in the pool, the longest life cycle value 0 means infinite life cycle, the default is 30 minutes 1800000 spring. The datasource. Hikari. Max - lifetime = 600000 # # database connection timeout, 30 seconds, by default The spring of 30000. The datasource. Hikari. Connection - the timeout = 30000 spring. The datasource. Hikari. Connection - test - query = SELECT 1Copy the codeBut when the project started, there was another warning:
WARN com.zaxxer.hikari.HikariConfig - Retail_HikariCP - idleTimeout is close to or more than maxLifetime, disabling it.
Copy the codeIdle-timeout +1 second >max-lifetime and max-lifetime>0. With two warnings, the problem of the HikariCP connection pool is understood more deeply. Change the maxLifetime value to a larger value than idle-timeout and set it to 800000 (13 minutes). Optimize the configuration file as follows according to the project situation:
# # database configuration spring. The datasource. Type = com. Zaxxer. Hikari. HikariDataSource spring. The datasource. DriverClassName = com.mysql.jdbc.Driver spring.datasource.u```rl = jdbc:mysql://localhost:3306/ssm? useUnicode=true&characterEncoding=utf-8&useSSL=false spring.datasource.username = root spring.datasource.password = root ## Hikari connection pool configuration ------ https://github.com/brettwooldridge/HikariCP # # minimum number of idle connections spring. The datasource. Hikari. Minimum - idle = 5 # # free connection for most time, The default 600000 (10 minutes) spring. The datasource. Hikari. Idle - timeout = 600000 # # connection pool maximum number of connections, Default is 10. Spring datasource. Hikari. Maximum - the pool - size = 10 # # this property control back from a pool of connections the default autocommit behaviour, default: True spring. The datasource. Hikari. Auto - commit = true # # connection pool and spring. The datasource. Hikari. The pool - name = testHikariCP # # This property control connections in the pool, the longest life cycle value 0 means infinite life cycle, the default is 30 minutes 1800000 spring. The datasource. Hikari. Max - lifetime = 800000 # # database connection timeout, 30 seconds, by default The spring of 30000. The datasource. Hikari. Connection - the timeout = 30000 spring. The datasource. Hikari. Connection - test - query = SELECT 1Copy the codeAfter optimization, it went live and the warning never happened again. Every time the line must pay attention to details, details are all knowledge points.