After the service restarts, the request is time-consuming in a short time

I am using sharding-jdbc 4.0.0-RC1.

      <dependency>
        <groupId>org.apache.shardingsphere</groupId>
        <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
        <version>4.0.0-RC1</version>
      </dependency>

question Online problem, every time you restart the project, after a successful restart, a request will appear in the persistence layer for a short time, such as 20 seconds. It takes a long time to appear, and then it will return to normal. At that time, the QPS is stable and the database connection is sufficient.

configuration

• spring.shardingsphere.datasource.ds0.type = com.zaxxer.hikari.HikariDataSource
• spring.shardingsphere.datasource.ds0.driver-class-name = com.mysql.jdbc.Driver
• spring.shardingsphere.datasource.ds0.maximum-pool-size = 100
• spring.shardingsphere.datasource.ds0.minimum-idle = 50
• spring.shardingsphere.datasource.ds0.connection-init-sql = SET NAMES utf8mb4

help

[beiwangnull]

@terrymanu @zcjhwl It’s going to be faster

@Component public class PreHeating implements InitializingBean { @Override public void afterPropertiesSet() throws Exception { Collection<DatabaseType> databaseTypes = SQLParserFactory.getAddOnDatabaseTypes(); for (DatabaseType databaseType:databaseTypes){ if(“MySQL”.equals(databaseType.getName())){ SQLParseEngine parseEngine = SQLParseEngineFactory.getSQLParseEngine(databaseType); parseEngine.parse(“select ‘X’”,true); MySQLParser mySQLParser = (MySQLParser)SQLParserFactory.newInstance(databaseType,“select ‘X’”); mySQLParser.execute(); } } }

[codingIsCrazy]

@terrymanu @zcjhwl It’s going to be faster

@component public class PreHeating implements InitializingBean { @override public void afterPropertiesSet() throws Exception { Collection databaseTypes = SQLParserFactory.getAddOnDatabaseTypes(); for (DatabaseType databaseType:databaseTypes){ if(“MySQL”.equals(databaseType.getName())){ SQLParseEngine parseEngine = SQLParseEngineFactory.getSQLParseEngine(databaseType); parseEngine.parse(“select ‘X’”,true); MySQLParser mySQLParser = (MySQLParser)SQLParserFactory.newInstance(databaseType,“select ‘X’”); mySQLParser.execute(); } } }

this “getAddOnDatabaseTypes” is not exist