1 工程概述

1.1 pom

 <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.71</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>4.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-logging</artifactId>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpcore</artifactId>
        </dependency>

    </dependencies>

1.2 RestTemplateConfig 配置

@Configuration
public class RestTemplateConfig {

    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

1.3 TestController

@RestController
@RequestMapping("/demo")
public class TestController {

    @Autowired
    private RestTemplate restTemplate;


    @GetMapping("/test")
    public String test() {
        ResponseEntity<String> forEntity = restTemplate.getForEntity("http://127.0.0.1:9000/demo/hello_world", String.class);
        return String.valueOf(forEntity.getStatusCodeValue());
    }


    @GetMapping("/hello_world")
    public String helloWorld()  {
        return "hello world";
    }

}

1.4 application.yml

server:
  port: 9000
  

1.5 主启动类

@SpringBootApplication
public class SpringDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringDemoApplication.class);
    }

}

1.6 测试

2 测试qps

jemeter： 60线程 5000次请求 10秒完成

结果： 700左右qps（并且持续下降），错误率还很高。

原因分析：

每次请求都会创建一个ClientHttpRequest，未能达到request复用，及其耗资源：

3 集成 ClientHttpRequestFactory

@Configuration
public class RestTemplateConfig {

    @Bean
    public RestTemplate restTemplate(ClientHttpRequestFactory requestFactory) {
        return new RestTemplate(requestFactory);
    }


    @Bean
    public ClientHttpRequestFactory httpRequestFactory() {
        return new HttpComponentsClientHttpRequestFactory(httpClient());
    }

    @Bean
    public HttpClient httpClient() {

        Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("http", PlainConnectionSocketFactory.getSocketFactory())
                .register("https", SSLConnectionSocketFactory.getSocketFactory())
                .build();

        PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager(registry);
        //设置连接池最大是100个连接
        connectionManager.setMaxTotal(1000);
        connectionManager.setDefaultMaxPerRoute(500);
        RequestConfig requestConfig = RequestConfig.custom()
                //返回数据的超时时间
                .setSocketTimeout(20000)
                //连接上服务器的超时时间
                .setConnectTimeout(10000)
                //从连接池中获取连接的超时时间
                .setConnectionRequestTimeout(1000).build();

        return HttpClientBuilder.create().setDefaultRequestConfig(requestConfig).setConnectionManager(connectionManager).build();
    }
}

结果： 1100 qps 并且稳定，没有错误。