Spring Boot 2. Hikari Connection Pool 优化答案

【问题标题】：Spring Boot 2. Hikari Connection Pool optimizationSpring Boot 2. Hikari Connection Pool 优化
【发布时间】：2018-10-05 10:42:24
【问题描述】：

我有一个 SpringBoot 应用程序，我正在控制器中进行一些性能测试，我意识到无论我放置控制器的第一个查询是什么，与其他查询相比，它需要很长时间......（数据库是远程连接，但我无法更改）

long t1 = System.nanoTime();

menuPriceSummaryService.findAllVegan().stream();            

long t2 = System.nanoTime();
long elapsedTimeInSeconds = (t2 - t1) / 1000000000;
System.out.println("elapsedTimeInSeconds1 -> " +  elapsedTimeInSeconds);

t1 = System.nanoTime();

menuPriceSummaryService.findAllVegan();

t2 = System.nanoTime();
elapsedTimeInSeconds = (t2 - t1) / 1000000000;
System.out.println("elapsedTimeInSeconds2 -> " +  elapsedTimeInSeconds);

t1 = System.nanoTime();
menuPriceSummaryService.findAllVegan().parallelStream();
t2 = System.nanoTime();
elapsedTimeInSeconds = (t2 - t1) / 1000000000;
System.out.println("elapsedTimeInSeconds3 -> " +  elapsedTimeInSeconds);

t1 = System.nanoTime();
menuPriceSummaryService.findAllVegan().parallelStream().filter(this::notInMyFavourites);
t2 = System.nanoTime();
elapsedTimeInSeconds = (t2 - t1) / 1000000000;

时间：

elapsedTimeInSeconds1 -> 76
elapsedTimeInSeconds2 -> 0
elapsedTimeInSeconds3 -> 0
elapsedTimeInSeconds4 -> 0

正常吗？我可以做些什么来配置 Hikari 池来优化它吗？

pom.xml

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
    <groupId>com.h2database</groupId>
    <artifactId>h2</artifactId>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

application.properties：

spring.datasource.url=jdbc:mysql://elcordelaciutat.awob1oxhu1so.eu-central-1.rds.amazonaws.com:3306/elcor
spring.datasource.username=elcor
spring.datasource.password=elcor2#$

spring.jpa.show-sql=false
spring.jpa.properties.hibernate.format_sql=true
hibernate.dialect=org.hibernate.dialect.MySQLDialect

【问题讨论】：

从SpringBoot 2.0.0开始，Spring的默认连接池是HikariCP而不是Tomcat。

标签： spring spring-boot authentication jdbc hikaricp

【解决方案1】：

你应该关注 Hikari 的MySQL Configuration:

HikariCP 的典型 MySQL 配置可能如下所示：

dataSource.cachePrepStmts=true
dataSource.prepStmtCacheSize=250
dataSource.prepStmtCacheSqlLimit=2048
dataSource.useServerPrepStmts=true
dataSource.useLocalSessionState=true
dataSource.useLocalTransactionState=true
dataSource.rewriteBatchedStatements=true
dataSource.cacheResultSetMetadata=true
dataSource.cacheServerConfiguration=true
dataSource.elideSetAutoCommits=true
dataSource.maintainTimeStats=false

【讨论】：