groupcache_datadog

README

groupcache_datadog

groupcache_datadog exports groupcache metrics to Datadog.

Usage

See example ./examples/groupcache-datadog-modernprogram/main.go.

Synopsis

import "github.com/udhos/dogstatsdclient/dogstatsdclient"
import "github.com/udhos/groupcache_datadog/exporter"
import "github.com/udhos/groupcache_exporter"
import "github.com/udhos/groupcache_exporter/groupcache/modernprogram"

cache := startGroupcache() // create the groupcache group (*groupcache.Group)

// create Dogstatsd client
client, errClient := dogstatsdclient.New(dogstatsdclient.Options{
    Namespace: "groupcache",
    Debug:     true,
})

// start the exporter
exporter := exporter.New(exporter.Options{
    Client:         client,
    Groups:         []groupcache_exporter.GroupStatistics{modernprogram.New(cache)},
    ExportInterval: 20 * time.Second,
})
defer exporter.Close()

Build example

git clone https://github.com/udhos/groupcache_datadog
cd groupcache_datadog
go install ./...

Running example

By default the example groupcache-datadog-modernprogram sends metrics to localhost:8125.

$ groupcache-datadog-modernprogram
2025/04/09 00:50:34 groupcache ttl: 30s
2025/04/09 00:50:34 groupcache my URL: http://127.0.0.1:5000
2025/04/09 00:50:34 INFO DD_AGENT_HOST=[] using DD_AGENT_HOST=localhost default=localhost
2025/04/09 00:50:34 groupcache server: listening on :5000
2025/04/09 00:50:34 INFO DD_AGENT_PORT=[] using DD_AGENT_PORT=8125 default=8125
2025/04/09 00:50:34 INFO DD_SERVICE=[] using DD_SERVICE=service-unknown default=service-unknown
2025/04/09 00:50:34 INFO DD_TAGS=[] using DD_TAGS= default=
2025/04/09 00:50:34 INFO NewDatadogClient host=localhost:8125 namespace=groupcache service=service-unknown tags=[service:service-unknown]
2025/04/09 00:50:34 getter: loading: key:/etc/passwd, ttl:30s
2025/04/09 00:50:34 INFO cache answer: bytes=2943 elapsed=50.548208ms, sleeping 5s

Datadog Count is a Delta

Definition

The COUNT metric submission type represents the total number of event occurrences in one time interval. A COUNT can be used to track the total number of connections made to a database or the total number of requests to an endpoint. This number of events can accumulate or decrease over time—it is not monotonically increasing.

Example

Suppose you are submitting a COUNT metric, notifications.sent, from a single host running the Datadog Agent. This host emits the following values in a flush time interval: [1,1,1,2,2,2,3,3].

The Agent adds all of the values received in one time interval. Then, it submits the total number, in this case 15, as the COUNT metric’s value.

Source: https://docs.datadoghq.com/metrics/types/?tab=count#definition