17. GeoMesa Metrics

GeoMesa provides integration with the DropWizard Metrics library for real-time reporting with the geomesa-metrics module.

17.1. Instrumentation of GeoServer

GeoMesa metrics provides a servlet filter that will instrument GeoServer requests.

17.2. Installation

Copy the following jars into geoserver’s WEB-INF/lib directory:

  • geomesa-metrics-.jar
  • metrics-core-3.1.2.jar
  • metrics-graphite-3.1.2.jar
  • metrics-ganglia-3.1.2.jar

Also copy the following jars if not already present:

  • scala-library-2.11.7.jar
  • scala-logging_2.11-3.1.0.jar
  • scala-reflect-2.11.7.jar
  • config-1.2.1.jar
  • joda-time-2.3.jar

17.2.1. Ganglia Reporting

To enable ganglia reporters, also copy the following jars:

  • gmetric4j-1.0.7.jar
  • oncrpc-1.0.7.jar

17.2.2. Delimited File Reporting

To enable TSV/CSV reporters, also copy the following jars:

  • commons-csv-1.0.jar

17.3. Configuration

To configure instrumentation, add the metrics filter to GeoServer’s WEB-INF/web.xml:

<filter>
  <filter-name>metricsFilter</filter-name>
  <filter-class>org.locationtech.geomesa.metrics.servlet.AggregatedMetricsFilter</filter-class>
  <!-- name used for registering metrics - can also be specified in the config, but this takes priority -->
  <init-param>
    <param-name>name-prefix</param-name>
    <param-value>geoserver</param-value>
  </init-param>
  <!-- can embed configuration directly, otherwise will load default
       configurations and look under 'geomesa.metrics.servlet' -->
  <init-param>
    <param-name>config</param-name>
    <param-value>
    {
      // name used for registering metrics - init-param takes precedence
      name-prefix = "geoserver"
      // will only instrument matching urls
      // example string matched against: '/geoserver/&lt;workspace&gt;/ows'
      url-patterns = [ "(?i).*/(ows|wfs|wms)" ]
      // match request mappings based on just the workspace:layer name, or the whole url
      // if you are instrumenting non-wfs/wms requests, layer names will never match
      map-by-layer = true
      // mappings of urls to metric groups, based on regexes
      // any urls not mapped will end up under 'other'
      request-mappings = [
        {
          name = "qs"
          regex = ".*:AccumuloQuickStart"
        }
      ]
      // metrics reporters - see configuration details below
      reporters = {
        console = {
          type = "console"
          rate-units = "MINUTES"
          duration-units = "MILLISECONDS"
          interval = 10
        }
      }
    }
    </param-value>
  </init-param>
</filter>

<filter-mapping>
  <filter-name>metricsFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

17.4. Session Tracking

The metrics servlet doesn’t track active user sessions by default. GeoServer mostly doesn’t create sessions for OWS requests, and blatantly warns you against doing so. However, if you are willing to incur the cost of session management, you may enable session tracking in the metrics servlet.

Update the configuration for the metrics servlet (either in application.conf or web.xml) with the following attribute:

// how often to update metrics for expired sessions, in seconds
// if set to &lt; 1, sessions will not be tracked
// use in conjunction with the session listener defined below
session-removal-interval = 60

Add the following listener to GeoServer’s WEB-INF/web.xml:

Warning

Failure to add this listener when session tracking is enabled will cause incorrect metrics reports and eventually lead to out-of-memory errors

<!-- listener for sessions events
     if you enable session tracking and this is not defined, sessions will never
     be expired from the metrics cache and you will eventually run out of memory -->
<listener>
  <listener-class>org.locationtech.geomesa.metrics.servlet.SessionMetricsListener</listener-class>
</listener>

In order to suppress GeoServer’s warnings about session creation, comment out the following filter in GeoServer’s WEB-INF/web.xml:

<!--
<filter>
  <filter-name>SessionDebugger</filter-name>
  <filter-class>org.geoserver.filters.SessionDebugFilter</filter-class>
</filter>
-->
...
<!--
<filter-mapping>
  <filter-name>SessionDebugger</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>
-->

17.5. Configuration of Reporters

Use org.locationtech.geomesa.metrics.config.MetricsConfig.reporters to configure reporters via TypeSafe Config. Reporters should be defined as objects under the path geomesa.metrics.reporters:

geomesa = {
  metrics = {
    reporters = {
      console = {
        type     = "console"
        units    = "MILLISECONDS"
        interval = 60
      }
      slf4j = {
        type     = "slf4j"
        units    = "MILLISECONDS"
        interval = 60
        logger   = "org.locationtech.geomesa"
        level    = "debug"
      }
      delimited-text = {
        type      = "delimited-text"
        units     = "MILLISECONDS"
        interval  = 60
        tabs      = true
        aggregate = true
        output    = ${java.io.tmpdir}/"geoserver-metrics"
      }
      graphite = {
        type     = "graphite"
        units    = "MILLISECONDS"
        interval = 60
        url      = "graphite.example.com:80"
        prefix   = "org.locationtech.geomesa"
      }
      ganglia = {
        type            = "ganglia"
        units           = "MILLISECONDS"
        interval        = 60
        group           = "ganglia.example.com"
        port            = 8649
        addressing-mode = "MULTICAST"
        ttl             = 1
        ganglia311      = true
      }
      accumulo = {
        type       = "accumulo"
        units      = "MILLISECONDS"
        interval   = -1
        instanceId = "mycloud"
        zookeepers = "zoo1,zoo2,zoo3"
        user       = "myuser"
        password   = "mypassword"
        tableName  = "geomesa_metrics"
      }
    }
  }
}

17.6. Standard Configuration

The following fields are common among all reporters:

Field Type Description
rate-units String The type of units used to report the rate of a metric. Corresponds to java.util.concurrent.TimeUnit
duration-units String The type of units used to report the duration of a metric. Corresponds to java.util.concurrent.TimeUnit
units String If rate or duration units are not specified, this will be used instead.
interval Integer How often the reporter will run, in seconds. If less than 1, reporter will not run automatically.
type String The type of reporter. Types are documented below.

17.6.1. Console Reporter

Writes metrics to the console.

Field Type Description
type String Must be console

17.6.2. Slf4j Reporter

Writes metrics using an slf4j logger.

Field Type Description
type String Must be slf4j
logger String The name of the logger that will be used for logging.
level String (optional) Level to use for logger messages. One of trace, debug, info, warn, error. Default is debug

17.6.3. Delimited Text Reporter

Writes metrics to tab or comma-delimited files.

Field Type Description
type String Must be delimited-text
output String The path to output metrics to. Will be passed into new java.io.File(output)
aggregate Boolean (optional) Aggregate output files by type. If true, there will be one file per metric type; if false there will be one file per metric. Default is true
tabs Boolean (optional) If true, delimit entries with tabs, else delimit entries with commas. Default is true

17.6.4. Graphite Reporter

Writes metrics to Graphite.

Field Type Description
type String Must be graphite
url String The URL to the graphite server, in the form of <host>:<port>
prefix String (optional) The graphite prefix to use

17.6.5. Ganglia Reporter

Writes metrics to Ganglia.

Field Type Description
type String Must be ganglia
group String The group (url) used for connecting to the ganglia server
port Int The port used for connecting to the ganglia server
ttl Int Time-to-live for broadcast packets, in the range of 0-255
addressing-mode String (optional) Addressing mode to use. Must be one of unicast or multicast
ganglia311 Boolean (optional) To use protocol version 3.1 (true) or 3.0 (false). Default is 3.1

17.6.6. Accumulo Reporter

Writes metrics to Accumulo.

Field Type Description
type String Must be accumulo
instanceId String The instance ID for the accumulo cluster
zookeepers String The zookeeper connection string for the accumulo cluster
user String The accumulo user to connect with
password String The password for the accumulo user
tableName String The table metrics will be written to
visibilities String (optional) Visibilities applied to written data