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by otterley 5066 days ago
I looked at Datadog, but they still suffer from the same malady everyone else does: inspired by Cacti and Graphite, they use a flat namespace for metric names (e.g. interfaces.eth0.pkts) and host is the only supported dimension you can query against. Unfortunately, none of the monitoring and analytics startups I'm aware of have support for arbitrary dimensions you can query or aggregate against (host, interface, disk, datacenter, etc.).

Without some understanding of the dimensions of the data, it is very difficult to compose dashboards or aggregation rules that have arbitrary filters or can update automatically when new components are added.

I really ought to elaborate in a blog post someday :)
1 comments
olidb2 5066 days ago
otterley - Don't walk away yet... we do support arbitrary dimensions!

You can attach any arbitrary set of tags to metrics or events - on a per-datapoint basis, and slice / dice / alert based on those tags. Datadog will automatically tag your points by chef role or AWS availability-zone, for example, and you can add any other tag you want. Tags also don't have to be tied to a host and can also relate to a specific volume, mysql index, etc...

(Note to HN, this is a feature of datadoghq - pup will gladly collect and filter on tags, but won't aggregate them, yet)

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otterley 5066 days ago
But tags aren't dimensions. Tags are merely a list of dimensionless values and completely lack context that are essential for dashboard construction and value aggregation.

Suppose I apply the tags "ord", "foo.example.com" and "bar.example.org" to a metric. How does the dashboard builder or the aggregator know what they are? They're values without the fields.

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olidb2 5065 days ago
Got it. Tags can be of the name:value kind. for ex: role:db or availability-zone:us-east-a1 or foo:bar

And you can then ask for "my.metric" summed over "availability-zone:us-east-1a" grouped by "role".

Here's a screenshot to show what it looks like https://skitch.com/oliveur/emywc/sobotka-datadog

You obviously have a lot of experience with monitoring tools - I'd love to connect. I'm @oliveur on the twitters.

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