Metrics

Gollum provide various metrics which can be used for monitoring or controlling.

Collecting metrics

To collect metrics you need to start the gollum process with the “-m <address:port>” option. If gollum is running with the “-m” option you are able to get all collected metrics by a tcp request in json format.

Example request:

# start gollum on host
gollum -m 8080 -c /my/config/file.conf

# get metrics by curl and prettify response by python
curl 127.0.0.1:8080 | python -m json.tool

# alternative by netcat
nc -d 127.0.0.1 8080 | python -m json.tool

Example response

{
    "Consumers": 3,
    "GoMemoryAllocated": 21850200,
    "GoMemoryGCEnabled": 1,
    "GoMemoryNumObjects": 37238,
    "GoRoutines": 20,
    "GoVersion": 10803,
    "Messages:Discarded": 0,
    "Messages:Discarded:AvgPerSec": 0,
    "Messages:Enqueued": 13972236,
    "Messages:Enqueued:AvgPerSec": 1764931,
    "Messages:Routed": 13972233,
    "Messages:Routed:AvgPerSec": 1764930,
    "Plugins:ActiveWorkers": 3,
    "Plugins:State:Active": 4,
    "Plugins:State:Dead": 0,
    "Plugins:State:Initializing": 0,
    "Plugins:State:PrepareStop": 0,
    "Plugins:State:Stopping": 0,
    "Plugins:State:Waiting": 0,
    "ProcessStart": 1501855102,
    "Producers": 1,
    "Routers": 2,
    "Routers:Fallback": 2,
    "Stream:profile:Messages:Discarded": 0,
    "Stream:profile:Messages:Discarded:AvgPerSec": 0,
    "Stream:profile:Messages:Routed": 13972239,
    "Stream:profile:Messages:Routed:AvgPerSec": 1768878,
    "Version": 500
}

Metrics overview

Global metrics

Consumers

Number of current active consumers.

GoMemoryAllocated

Current allocated memory in bytes.

GoMemoryGCEnabled

Indicates that GC is enabled.

GoMemoryNumObjects

The number of allocated heap objects.

GoRoutines

The number of active go routines.

GoVersion

The golang version in number format.

Messages:Discarded

The count of discarded messages over all.

Messages:Discarded:AvgPerSec

The average of discarded messages from the last seconds.

Messages:Enqueued

The count of enqueued messages over all.

Messages:Enqueued:AvgPerSec

The average of enqueued messages from the last seconds.

Messages:Routed

The count of routed messages over all.

Messages:Routed:AvgPerSec

The average of routed messages from the last seconds.

Plugins:ActiveWorkers

Number of active worker (plugin) processes.

Plugins:State:<STATE>

Number of plugins in specific states. The following states can possible for plugins:

• Active
• Dead
• Initializing
• PrepareStop
• Stopping
• Waiting

ProcessStart

Timestamp of the process start time.

Producers

Number of current active producers.

Routers

Number of current active routers.

Routers:Fallback

Number of current active “fallback” (auto created) routers.

Version

Gollum version as numeric value.

Stream based metrics

Stream:<STREAM_NAME>:Messages:Discarded

The count of discarded messages for a specific stream.

Stream:<STREAM_NAME>:Messages:Discarded:AvgPerSec

The average of discarded messages from the last seconds for a specific stream.

Stream:<STREAM_NAME>:Messages:Routed

The count of routed messages for a specific stream.

Stream:<STREAM_NAME>:Messages:Routed:AvgPerSec

The average of routed messages from the last seconds for a specific stream.