HikariCP Connection Pool Cannot Recover After MySQL Connection Failure

[ledinhtuyenbkdn]

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HikariCP Connection Pool Cannot Recover After MySQL Connection Failure

Environment

Component	Version
Application	Spring Boot 3.3.4
Java	17
Connection Pool	HikariCP 5.1.0
Database	Amazon RDS MySQL 8

Current Configuration

application.yml:

spring:
  datasource:
    hikari:
      poolName: Hikari
      auto-commit: false
      max-pool-size: 30
      minimum-idle: 10
      data-source-properties:
        cachePrepStmts: true
        prepStmtCacheSize: 250
        prepStmtCacheSqlLimit: 2048
        useServerPrepStmts: true

Problem Description

When the application experiences a connection issue to the MySQL server, the connection pool drops to zero and cannot recover automatically. The connection issue only occurs for a short time (several seconds), but the pool still fails to recover. A manual application restart is required to restore functionality.

Logs

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Caused by: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure

... 181 more

at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:126)

at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:46)

at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122)

at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:127)

at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:144)

at com.zaxxer.hikari.pool.HikariPool.getConnection(HikariPool.java:179)

at com.zaxxer.hikari.pool.HikariPool.createTimeoutException(HikariPool.java:696)
Caused by: java.sql.SQLTransientConnectionException: Hikari - Connection is not available, request timed out after 30000ms (total=0, active=0, idle=0, waiting=3)

... 178 more

at org.springframework.orm.jpa.JpaTransactionManager.doBegin(JpaTransactionManager.java:428)

at org.springframework.orm.jpa.vendor.HibernateJpaDialect.beginTransaction(HibernateJpaDialect.java:164)

at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.getPhysicalConnection(LogicalConnectionManagedImpl.java:156)

at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:129)

at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:94)

at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:108)

at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:58)

at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:51)
Caused by: org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection [Hikari - Connection is not available, request timed out after 30000ms]

at java.base/java.lang.Thread.run(Unknown Source)

at org.xnio.XnioWorker$WorkerThreadFactory$1$1.run(XnioWorker.java:1282)

at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)

Expected Behavior

The connection pool should automatically recover and establish new connections after a temporary network/database failure.

Actual Behavior

Connection pool drops to zero (total=0, active=0, idle=0, waiting=3) and does not recover. Application restart is required.