Start your Engines - White box Monitoring for your Load Tests

You think monitoring is only for production? Wrong: Add a metrics endpoint to your application to get insights during your load tests - and use them for free to monitor production!

This talk shows how to setup up the load testing tools JMeter and Gatling to push their metrics to Prometheus. It also makes the case to expose metrics as part of core application development instead of treating them as a small add-on before go-live.

Transcript

1. .consulting .solutions .partnership
   Start your Engines
   White Box Monitoring for your Load Tests
   Alexander Schwartz, Principal IT Consultant
   Continuous Lifecyle London 2018-05-17
   

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2. Start your Engines – Whitebox Monitoring for your Load Tests
   2
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz
   Why to use load tests
   1
   Setup of the test environment
   2
   Demo
   3
   What to expect
   4
   

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3. Start your Engines – Whitebox Monitoring for your Load Tests
   5
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz
   Why to use load tests
   1
   Setup of the test environment
   2
   Demo
   3
   What to expect
   4
   

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4. Why to use load tests
   Naive Approach
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 6
   Development Test Production
   

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5. Why to use load tests
   Alternative Approach with Load Testing and Monitoring
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 7
   Production
   Development Test
   

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6. Start your Engines – Whitebox Monitoring for your Load Tests
   8
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz
   Why to use load tests
   1
   Setup of the test environment
   2
   Demo
   3
   What to expect
   4
   

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7. Setup of the Environment
   Monitoring
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 9
   Host & Application
   Metrics
   Alerts
   Dashboards
   

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8. Setup of the Environment
   Prometheus is a Monitoring System and Time Series Database
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 10
   Prometheus is an opinionated solution
   for
   instrumentation, collection, storage
   querying, alerting, dashboards, trending
   

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9. Prometheus Manifesto
   1. PromCon 2016: Prometheus Design and Philosophy - Why It Is the Way It Is - Julius Volz
   https://youtu.be/4DzoajMs4DM / https://goo.gl/1oNaZV
   Prometheus values …
   © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 11
   operational systems monitoring
   (not only) for the cloud
   simple single node
   w/ local storage for a few weeks
   horizontal scaling, clustering,
   multitenancy
   raw logs and events, tracing of requests, magic
   anomaly detection, accounting, SLA reporting
   over
   over
   over
   over
   over
   configuration files Web UI, user management
   pulling data from single processes
   pushing data from processes,
   aggregation on nodes
   NoSQL query & data massaging
   multidimensional data
   everything as float64
   point-and-click configurations,
   data silos,
   complex data types
   

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10. Setup of the Environment
    Purple (including Prometheus): Provided as infrastructure in a testing environment
    Blue: Setup and maintained by product team (developers/testers)
    Arrows: Direction of communication
    Technical Building Blocks
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 12
    Grafana
    Container:
    cadvisor
    Java Application:
    simple_client
    Load Test Metrics:
    graphite_exporter
    Load Test:
    Gatling or JMeter
    Dashboards
    Host:
    node_exporter
    push
    call
    pull
    pull
    pull
    pull
    query
    

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11. Setup of the Environment
    Targets as configured in Prometheus Configuration
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 17
    scrape_configs:
    - job_name: 'node-exporter'
    scrape_interval: 5s
    static_configs:
    - targets: ['172.17.0.1:9100']
    

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12. Setup
    CPU Metric as exported by the Node Exporter
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 18
    # HELP node_cpu Seconds the cpus spent in each mode.
    # TYPE node_cpu counter
    node_cpu{cpu="cpu0",mode="guest"} 0
    node_cpu{cpu="cpu0",mode="idle"} 4533.86
    node_cpu{cpu="cpu0",mode="iowait"} 7.36
    ...
    node_cpu{cpu="cpu0",mode="user"} 445.51
    node_cpu{cpu="cpu1",mode="guest"} 0
    node_cpu{cpu="cpu1",mode="idle"} 4734.47
    ...
    node_cpu{cpu="cpu1",mode="iowait"} 7.41
    node_cpu{cpu="cpu1",mode="user"} 576.91
    ...
    

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13. Setup
    Multidimensional Metric as stored by Prometheus
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 19
    576.91
    cpu: cpu1
    instance: 172.17.0.1:9100
    job: node-exporter
    __name__: node_cpu
    mode: user
    

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14. Setup
    Calculations based on metrics
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    Metric:
    node_cpu: Seconds the CPUs spent in each mode (Type: Counter).
    What percentage of a CPU is used per core?
    1 - rate(node_cpu{mode='idle'} [5m])
    What percentage of a CPU is used per instance?
    avg by (instance) (1 - rate(node_cpu{mode='idle'} [5m]))
    function filter parameter
    metric
    

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15. How to…
    Information about your containers
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 21
    Presented by: cadvisor
    RAM Usage per container:
    Metric: container_memory_usage_bytes
    Expression: container_memory_usage_bytes{name=~'.+',id=~'/docker/.*'}
    CPU Usage per container:
    Metric: container_cpu_usage_seconds_total
    Expression: rate(container_cpu_usage_seconds_total [30s])
    irate(container_cpu_usage_seconds_total [30s])
    sum by (instance, name) (irate(container_cpu_usage_seconds_total{name=~'.+'} [15s]))
    

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16. How to…
    Information about your JVM
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 22
    Presented by: Java simple_client
    RAM Usage of Java VM:
    Metric: jvm_memory_bytes_used
    Expressions: sum by (instance, job) (jvm_memory_bytes_used)
    sum by (instance, job) (jvm_memory_bytes_committed)
    CPU seconds used by Garbage Collection:
    Metric: jvm_gc_collection_seconds_sum
    Expression: sum by (job, instance) (irate(jvm_gc_collection_seconds_sum [10s]))
    

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17. 
    io.prometheus
    simpleclient_spring_boot
    ${simpleclient.version}
    
    How to…
    Information about your JVM
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 23
    Alternative 1: Add Prometheus‘ Java Simple Client for Spring Boot to serve standard JVM metrics using
    /prometheus actuator endpoint.
    @Configuration
    @EnablePrometheusEndpoint
    public class ApplicationConfig {
    @PostConstruct
    public void metrics() {
    DefaultExports.initialize();
    /* ... */
    }
    }
    

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18. How to…
    Information about your JVM
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 24
    Alternative 2: Add a Micrometer.io to serve standard Spring metrics using /prometheus actuator endpoint.
    
    io.micrometer
    
    micrometer-spring-legacy
    ${micrometer.version}
    
    
    io.micrometer
    micrometer-registry-prometheus
    ${micrometer.version}
    
    

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19. How to…
    Information about your Application Metrics
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 25
    Presented by: Micrometer and Spring
    Timings of a method call:
    Java Annotation: @Timed(value = "doSomething", description = "...")
    Metrics: doSomething_count
    doSomething_sum
    

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20. How to…
    Information about your Application Metrics
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 26
    Add a Configuration to collect timings from Annotations.
    @Configuration
    public class MetricsApplicationConfig {
    // as of now, this aspect needs to be created manually, see
    // https://github.com/micrometer-metrics/micrometer/issues/361
    @Bean
    public TimedAspect timedAspect(MeterRegistry registry) {
    return new TimedAspect(registry);
    }
    }
    

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21. How to…
    Information about your Application Metrics
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 27
    Add @Timed annotations to any method of any Bean to collect metrics
    @Component
    public class ServiceClass {
    @Timed(value = "doSomething", description = "...")
    public void doSomething() {
    log.info("hi");
    }
    }
    

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22. How to…
    Information about your External Interfaces
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 28
    Presented by: Java simple_client, Hystrix/Spring
    Hystrix Metrics:
    Java Annotation: @HystrixCommand
    Metrics: hystrix_command_total {command_name="externalCall", …}
    hystrix_command_event_total {command_name="externalCall", event="success", …}
    Expressions: histogram_quantile(0.99,
    rate(hystrix_command_latency_execute_seconds_bucket[1m]))
    

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23. How to…
    Information about your External Interfaces – Hystrix Metrics
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 29
    Register the Hystrix Publisher and add @HystrixCommand for resilience and timing of external calls.
    HystrixPrometheusMetricsPublisher.builder() /*...*/ .register();
    @Component
    public class ExternalInterfaceAdapter {
    @HystrixCommand(commandKey = "externalCall", groupKey = "interfaceOne")
    public String call() {
    /* ... */
    }
    }
    

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24. Start your Engines – Whitebox Monitoring for your Load Tests
    30
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz
    Why to use load tests
    1
    Setup of the test environment
    2
    Demo
    3
    What to expect
    4
    

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25. Demo
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 31
    

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26. Start your Engines – Whitebox Monitoring for your Load Tests
    32
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz
    Why to use load tests
    1
    Setup of the test environment
    2
    Demo
    3
    What to expect
    4
    

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27. What to expect
    Metrics the teams used in their Dashboards to monitor tests
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 33
    From infrastructure:
    • CPU usage per container
    • RAM usage per container
    From application:
    • Standard runtime metrics
    • Counters
    • Gauges [gājez] for Queues and Pools
    • Dropwizard and Micrometer Metrics
    • Timings for dependent services from Neflix’ circuit breaker library Hystrix
    

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28. What to expect
    1. http://www.brendangregg.com/usemethod.html
    2. https://www.weave.works/blog/prometheus-and-kubernetes-monitoring-your-applications/
    3. https://landing.google.com/sre/book/chapters/monitoring-distributed-systems.html#xref_monitoring_golden-signals
    Lessons learned
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 34
    The approach worked well for us to pass the load tests:
    • Load Tool metrics correlated with application and infrastructure metrics
    • Inter-application communication captured by Hystrix
    • Self-service functionality for product teams to add applications and metrics
    … but to use the instrumentation also in production create awareness for:
    • Exported metrics should following Prometheus naming conventions
    • Collector for Dropwizard Metrics can’t fill HELP text of metrics
    • Counters and averages vs. histograms, summaries and percentiles
    • Consistent use of either USE Method (utilization – saturation – errors),
    RED Method (rate – errors – duration) or
    Google’s Four Golden Signals (latency – traffic – errors – saturation) for metrics
    

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29. Prometheus works for Developers (and Ops)
    Prometheus is “friendly tech” in your environment
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 35
    Team friendly
    • Every team can run its own Prometheus instance to monitor their own and neighboring systems
    • Flexible to collect and aggregate the information that is needed
    Coder and Continuous Delivery friendly
    • All configurations (and exported dashboard) are kept as code and are guarded by version control
    • Changes can be tested locally and easily staged to the next environment
    Simple Setup
    • Go binaries for prometheus and alertmanager available for major operating systems
    • Client libraries for several languages available (also adapters to existing metrics libraries)
    • Several existing exporters for various needs
    

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30. Links
    © msg | May 2018 | Start your Engines – White Box Monitoring for Load Tests | Alexander Schwartz 36
    Prometheus:
    https://prometheus.io
    Java Simple Client
    https://github.com/prometheus/client_java
    Dropwizard Metrics
    http://metrics.dropwizard.io
    Prometheus Hystrix Metrics Publisher
    https://github.com/ahus1/prometheus-hystrix
    Micrometer.io
    https://micrometer.io @ahus1de
    Apache JMeter
    http://jmeter.apache.org/
    Gatling
    http://gatling.io/
    CAdvisor
    https://github.com/google/cadvisor
    Link to Videos and Slides
    https://www.ahus1.de/post/prometheus-and-
    grafana-talks
    

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31. .consulting .solutions .partnership
    Alexander Schwartz
    Principal IT Consultant
    +49 171 5625767
    alexander.schwartz@msg.group
    @ahus1de
    msg systems ag (Headquarters)
    Robert-Buerkle-Str. 1, 85737 Ismaning
    Germany
    www.msg.group
    

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