Graphing functions

[opentsdb]

Graphing functions

[tsuna]

You can plot a time series against another. What you're describing I guess is doing arithmetic operations between time series (e.g. divide number of requests by number of errors to get the error rate).

This is a feature I really wanna have but is probably kinda tricky to implement, so is going to be deferred for now.

[fastolfe]

It seems like you could implement this by creating an expression language, with expressions exposed as a DataPoints object. Support regular binary arithmetic operations between timeseries and timeseries, or timeseries and constants. It would be useful also to be able to compute derivatives of a timeseries (is query latency trending upward right now?) in a similar fashion. It should be flexible enough to allow me to take historical averages of a timeseries, and compute the deviation from that average as its own timeseries.

Take a look at http://r-project.org/, which is a statistical analysis language and implementation. It seems to have a decent support for performing operations on timeseries data. It would be nice to re-use an existing language/platform for this.

It might also be nice to be able to compute the results of an expression like this and write data points back to the TSD, or evaluate these expressions from the command line so we can generate alerting based on ratios and the like.

[acirillo]

Just dividing one metric by another is 85% of what I would need.

[chuyskywalker]

I'd like to resurrect this issue. Our statsd/graphite/carbon graphing system is coming to a vertical scaling ceiling and OpenTSDB looks like it blows right past such issues -- but I'm desperately missing the expressiveness of creating composite on-the-fly graphs like I can in graphite. Their function list is quite extensive and really lets you massage the data into making sense.

[vitorboschi]

Was there any progress on this issue? Operations on metrics are a really useful thing to have

[jongwook]

+1

[johann8384]

These are now added to OpenTSDB in the 2.3 branch. http://opentsdb.net/docs/build/html/api_http/query/gexp.html