JVM监控：springboot actuator + springboot admin

最近几个月天天加班，好久没更新博客了。
这两天排查一个CPU飙高导致服务假死的问题，常规套路：
jps
top -H -p 进程ID
jstack -l 高CPU线程
以上常规套路相信大家都比较熟练，但是当节点比较多的时候，就需要挨个进到机器或容器内，查看jvm堆栈情况，耗时耗力，如果能使用可视化工具就方便多了。Arthas（阿尔萨斯）需要单独部署成进程，部署复杂；springboot actuator作为信息采集客户端，springboot admin作为可视化页面，侵入性较小，因此选择后者，废话不多，上代码

1、业务服务（监控客户端）

1）pom

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>de.codecentric</groupId>
            <artifactId>spring-boot-admin-starter-client</artifactId>
            <version>2.3.1</version>
        </dependency>

2）配置

server:
  port: 8080
spring:
  application:
    name: test_server
    admin:
      enabled: true
  boot:
    admin:
      client:
        # 如果不是在同一个节点，只要使用内网地址和端口即可，容器部署需要将容器端口映射到宿主机
        # springboot admin server 地址
        url: http://127.0.0.1:3001
        # springboot admin client 地址
        instance:
          service-url: http://127.0.0.1:8080


# springboot actuator
management:
  endpoints:
    web:
      exposure:
        include: info,health,metrics,httptrace,env,scheduledtasks,threaddump,heapdump
  endpoint:
    health:
      show-details: always

2、监控及可视化服务（监控服务端）

1）pom

    <dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>de.codecentric</groupId>
				<artifactId>spring-boot-admin-dependencies</artifactId>
				<version>${
    
    spring-boot-admin.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>de.codecentric</groupId>
			<artifactId>spring-boot-admin-starter-server</artifactId>
		</dependency>
	</dependencies>

2）配置

server:
  port: 3001
spring:
  application:
    name: springboot-admin-server
    admin:
      enabled: true

3）启动类

import de.codecentric.boot.admin.server.config.EnableAdminServer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@EnableAdminServer
public class SpringbootAdminApplication {
    
    

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

}

注：springboot actuator除默认监控指标外，还支持自定义监控指标，例如监控数据库连接池使用情况，可在代码中添加

import com.alibaba.druid.pool.DruidDataSource;
import com.baomidou.dynamic.datasource.DynamicRoutingDataSource;
import com.baomidou.dynamic.datasource.ds.ItemDataSource;
import com.zaxxer.hikari.HikariDataSource;
import com.zaxxer.hikari.HikariPoolMXBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.actuate.health.AbstractHealthIndicator;
import org.springframework.boot.actuate.health.Health;
import org.springframework.stereotype.Component;

import javax.sql.DataSource;
import java.util.Map;

@Component
public class HealthIndicato extends AbstractHealthIndicator {
    
    

    @Autowired
    private DataSource dataSource;

    @Autowired(required = false)
    private HikariDataSource hikariDataSource;

    @Autowired(required = false)
    private DynamicRoutingDataSource dynamicRoutingDataSource;

    @Override
    protected void doHealthCheck(Health.Builder builder) throws Exception {
    
    
        // MySQL连接监控
        if (dataSource != null) {
    
    
            if (dataSource instanceof HikariDataSource) {
    
    
                HikariDataSource hikariDataSource = (HikariDataSource) dataSource;
                HikariPoolMXBean mysqlPool = hikariDataSource.getHikariPoolMXBean();
                builder.up()
                        .withDetail("mysql-total-connections", mysqlPool.getTotalConnections())
                        .withDetail("mysql-active-connections", mysqlPool.getActiveConnections())
                        .withDetail("mysql-idle-connections", mysqlPool.getIdleConnections())
                        .withDetail("mysql-threads-awaiting-connection", mysqlPool.getThreadsAwaitingConnection());
            } else if (dataSource instanceof DynamicRoutingDataSource) {
    
    
                DynamicRoutingDataSource dynamicRoutingDataSource = (DynamicRoutingDataSource) dataSource;
                Map<String, DataSource> dataSourceMap = dynamicRoutingDataSource.getCurrentDataSources();
                for (Map.Entry<String, DataSource> entry : dataSourceMap.entrySet()) {
    
    
                    String key = entry.getKey();
                    ItemDataSource itemDataSource = (ItemDataSource) entry.getValue();
                    DruidDataSource druidDataSource = (DruidDataSource) itemDataSource.getRealDataSource();
                    builder.up()
                            .withDetail("mysql-" + key + "-ConnectCount", druidDataSource.getConnectCount())
                            .withDetail("mysql-" + key + "-CloseCount", druidDataSource.getCloseCount())
                            .withDetail("mysql-" + key + "-ConnectErrorCount", druidDataSource.getConnectErrorCount())
                            .withDetail("mysql-" + key + "-PoolingCount", druidDataSource.getPoolingCount())
                            .withDetail("mysql-" + key + "-ActiveCount", druidDataSource.getActiveCount())
                            .withDetail("mysql-" + key + "-NotEmptyWaitCount", druidDataSource.getNotEmptyWaitCount())
                            .withDetail("mysql-" + key + "-NotEmptyWaitThreadCount", druidDataSource.getNotEmptyWaitThreadCount());
                }
            }
        }
    }
}