Set counter metric to a specific value

Question

Set counter metric to a specific value

dctc42 opened this issue 5 years ago · comments

My team came across an edge case where we need to set a counter metric to a specific value to compensate for changes made offline/operationally in a database.

I tried combining counter and gauge operations with the same metric name but this generates two time series in our metrics backend (we use Wavefront).

Is there a way to set a counter type metric to a specific value?

dctc42 commented 5 years ago

Thanks!

Elliot Blackburn · Answer 1 · Fri Dec 13 2019 04:28:45 GMT+0800 (China Standard Time)

Hi @dctc42, there's nothing to set a counter to a particular level at the moment. However you can increment by any desired amount (see https://github.com/statsd/statsd/blob/master/docs/metric_types.md#counting).

If you want to set a counter to a specific value then there would probably need to be something added to the statsd protocol to support it. Do gauges definetely not fit your use case? It sounds like you're more worried about an ending value, than incrementing by set amounts.

dctc42 · Answer 2 · Fri Dec 13 2019 23:00:18 GMT+0800 (China Standard Time)

Thanks for your reply, @BlueHatbRit . I think we'll need to use gauges. I think the issue we're facing is consistency. App developers want to track operations that mostly match to rows in DB tables. The problem is there too many ways the DB can change outside the application.

Elliot Blackburn · Answer 3 · Fri Dec 13 2019 23:19:19 GMT+0800 (China Standard Time)

@dctc42 that's an interesting use case! I'm not sure what database you're using, but you could consider using a database trigger to call out to a script/service that can handle the tracking for you. Then in that scenario, the database (as the authoratative source) will be able to trigger the incrementing event for you.

dctc42 · Answer 4 · Sat Dec 14 2019 00:01:19 GMT+0800 (China Standard Time)

@BlueHatbRit This is a legacy app with a lot of performance issues. The DB (MSSQL)is basically an app server so I would be concerned about adding triggers in this type of environment.

Maybe change data capture functionality could help with this

Elliot Blackburn · Answer 5 · Sat Dec 14 2019 00:22:46 GMT+0800 (China Standard Time)

😞 that's a shame, best of luck with the implementation. If this feature is something we can find a way to justify existing in the statsd protocol then I'm sure we'd be up for considering it, but we've not had the need to implement it so far so it doesn't currently exist.