David Kaltschmidt c93e54d240 Adds execution timer stats to the range query ... API consumers should be able to get insight into the query run times. The UI currently measures total roundtrip times. This PR allows for more fine grained metrics to be exposed. * adds new timer for total execution time (queue + eval) * expose new timer, queue timer, and eval timer in stats field of the range query response: ```json { "status": "success", "data": { "resultType": "matrix", "result": [], "stats": { "execQueueTimeNs": 4683, "execTotalTimeNs": 2086587, "totalEvalTimeNs": 2077851 } } } ``` * stats field is optional, only set when query parameter `stats` is not empty Try it via ```sh curl 'http://localhost:9090/api/v1/query_range?query=up&start=1486480279&end=1486483879&step=14000&stats=true' ``` Review feedback * moved query stats json generation to query_stats.go * use seconds for all query timers * expose all timers available * Changed ExecTotalTime string representation from Exec queue total time to Exec total time		2017-11-16 16:05:10 +01:00
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query_stats.go	Adds execution timer stats to the range query	2017-11-16 16:05:10 +01:00
timer.go	Adds execution timer stats to the range query	2017-11-16 16:05:10 +01:00