14.1.1 promethues monitoring, four data types metrics, pushgateway

1、4 Common use Metrics

1）Counter

Continuously increasing a counter that does not decrease , It can be used to record types that only increase but not decrease , for example ： Number of visitors to the site , System running time, etc .

about Counter Indicators of type , Contains only one inc() Methods , It's used for counters +1.

generally speaking ,Counter Type of metric Indicators are used in the dark _total end , Such as http_requests_total.

2）Gauge

A dashboard that can be added or subtracted , diagram

For such indicators that can be increased or decreased , Used to reflect the current state of the application .

For example, when monitoring the host , The current idle memory size of the host , Available memory size, etc .

about Gauge The object of the indicator contains two main methods inc() and dec(), Used to increase and decrease counts .

3）Histogram

It is mainly used to count the distribution of data , This is a special metrics data type , Represents an approximate percentage estimate , Count the times of all discrete indicator data in each value range . for example ： We want to make statistics for a period of time http The request response is less than 0.005 second 、 Less than 0.01 second 、 Less than 0.025 Second data distribution . So use Histogram Every acquisition http Requested time , Simultaneous setting bucket.

4）Summary

Summary and Histogram Very similar , You can count the number or size of events , And its distribution , They all provide a count of time _count And a summary of the values _sum, It also provides the function of calculating the distribution of statistical samples , The difference is Histogram Can pass histogram_quantile The quantile() function calculates the quantile on the server . and Sumamry The quantile of is defined directly on the client . So for the quantile calculation ,Summary Through PromQL Better performance when querying , and Histogram It will consume more resources , But relative to the client Histogram Less resources are consumed . You can use either , It can be adjusted freely according to the actual scene .

2、 be based on SpringBoot Write a simple exporter

1）pom.xml The configuration is as follows

4 individual prometheus The dependent package and two pushgateway The dependency package of

 <!-- Prometheus relied on -->
        <dependency>
            <groupId>io.prometheus</groupId>
            <artifactId>simpleclient_spring_boot</artifactId>
            <version>0.4.0</version>
        </dependency>
        <dependency>
            <groupId>io.prometheus</groupId>
            <artifactId>simpleclient_hotspot</artifactId>
            <version>0.4.0</version>
        </dependency>
        <dependency>
            <groupId>io.prometheus</groupId>
            <artifactId>simpleclient_servlet</artifactId>
            <version>0.4.0</version>
        </dependency>
		<dependency>
			<groupId>io.prometheus</groupId>
			<artifactId>simpleclient_pushgateway</artifactId>
			<version>0.4.0</version>
		</dependency>
        <!--springboot-->
		<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>

2）Application Class annotation

add to @EnableScheduling Annotations mainly add scheduled tasks , Used to dynamically simulate changes in data , You will see the application later

@SpringBootApplication
@EnableScheduling
@EnablePrometheusEndpoint
@EnableSpringBootMetricsCollector
public class ExporterDemoApplication{
    
 
	public static void main(String[] args) {
    
		SpringApplication.run(ExporterDemoApplication.class, args);
	}
}

3）CounterTest

Define a Counter Type of metrics, generally speaking ,Counter Type of metrics In the naming of indicators, we use _total end .

@RestController
public class CounterTest {
    
    /* *  Use Counter.build() establish Counter Type of monitoring indicators , And through name() Method defines the name of the monitoring indicator network_traffic_input * , adopt labelNames() Define the labels included in this indicator . Finally through register() Register the indicator to Collector Of defaultRegistry in  */
    static final Counter counterDemo = Counter.build()
            .name("counterChanger_job").labelNames("ddd","ccc","unit")
            .help("Counter  example ").register();
    // Indicators buried point , The timer will cause Prometheus to be out of sync with the local data timestamp , Try not to use this way , The timer in the example is for data demonstration 
    @Scheduled(cron="0/5 * * * * ?")
    @RequestMapping("/changeCounter")
    public  void changeCounter(){
    
      counterDemo.labels(" label 1"," label 2","seconds").inc();// The index value increases 
  }
}

Here every 5 Seconds will be executed automatically changeCounter Used to simulate changes in data

4）GaugeTest

@RestController
public class GaugeTest {
    
    /** Indicator registration  * name Set the index name  * labelNames Set the name of each indicator  * help Set indicator description  */
    static final Gauge gaugeDemo = Gauge.build()
            .name("gaugeDemo")
            .labelNames("label1","label2","label3","label4","label5")
            .help("gauge  example ").register();
 
    // Indicators buried point 
    @Scheduled(cron="0/5 * * * * ?")
    @RequestMapping("/changeGauge")
    public  void  changeGauge() {
    
        gaugeDemo.labels("1","2","3","4","5").inc(); // Index value plus 1
        gaugeDemo.labels("1","2","3","4","5").dec(); // The index value is reduced by one 
        gaugeDemo.labels("1","2","3","4","5").set(19.00); // The indicator value is directly assigned 
    }
}

Gauge Type of metrics Data can be added 、 Reduction and direct assignment . This type is more common in practical applications

5）HistogramTest

@RestController
public class HistogramTest
{
    
    /** *  register  *  Registration time buckets() Set interval value , The following settings 100、200、300 Three interval values  */
    static final Histogram histogramDemo = Histogram.build()
                                                    .labelNames("label1", "label2", "label3", "label4", "label5")
                                                    .name("histogramDemo")
                                                    .buckets(100, 200, 300)
                                                    .help("Histogram  example ")
                                                    .register();
    // Indicators buried point 
    @Scheduled(cron = "0/5 * * * * ?") 
    public void changeHistogram()
    {
    
        /** *  The index value implemented this time  *  Set as 150, Every time , Less than 200 Interval and less than 300 Interval plus 1, Less than 100 Interval invariant  */
        histogramDemo.labels("1", "2", "3", "4", "5").observe(150);
    }
}

6）SummaryTest

@RestController
public class SummaryTest {
    
    // register 
    static final Summary summaryDemo = Summary.build()
            .quantile(0.5, 0.01)   //  add to 50% quantile , Allow 5% The error of the , Equivalent to finding the median 
            .quantile(0.9, 0.01)   //  add to 90% quantile , Allow 1% The error of the 
            .name("summaryDemo").labelNames("label1","label2","label3","label4","label5")
            .help("Summary  example ").register();
    // Indicators buried point 
    @Scheduled(cron="0/5 * * * * ?")
    public  void  changeSummary(){
    
        summaryDemo.labels("1","2","3","4","5").observe(1);
    }
}

stay prometheus Of Graph View through summaryDemo、summaryDemo_count、summaryDemo_sum View the corresponding results

7）pushgateway

@Component
public class PrometheusConfig
{
    
    public static final Counter counterDemo = Counter.build()
                                                        .name("push_way_counter")
                                                        .labelNames("wy","zxjr","ocs","xxjf","unit","instance")
                                                        .help("Counter  example ")
                                                        .register();
    // Test send 
    public static void main(String[] args)
    {
    
        PushGateway prometheusPush = new PushGateway("localhost:9091");
        try
        {
    
            for(int i=0;i<50;i++){
    
                counterDemo.labels(" Network element "," Online access ","OCS"," Message billing ","byte","localhsot:9091").inc();
                prometheusPush.push(counterDemo,"sp-getway");
                Thread.sleep(5000);
            }
        }
        catch (Exception e)
        {
    
            e.printStackTrace();
        }
    }
}

reference ：

1）promethues Official website