Summary and Histogram Format

A Summary looks like:

go_gc_duration_seconds{quantile="0"} 0.000236554
go_gc_duration_seconds{quantile="0.25"} 0.000474629
go_gc_duration_seconds{quantile="0.5"} 0.0005691670000000001
go_gc_duration_seconds{quantile="0.75"} 0.000677597
go_gc_duration_seconds{quantile="1"} 0.002479919
go_gc_duration_seconds_sum 12.532527861
go_gc_duration_seconds_count 24279

In addition to the _sum and _count, there are time series for each quantile.

A Histogram looks like:

request_latency_seconds_bucket{le="0.025"} 4.0
request_latency_seconds_bucket{le="0.05"} 7.0
request_latency_seconds_bucket{le="0.075"} 10.0
request_latency_seconds_bucket{le="1.0"} 10.0
request_latency_seconds_bucket{le="+Inf"} 11.0
request_latency_seconds_count 11.0
request_latency_seconds_sum 3.3

In addition to the _sum and _count, there are time series for each bucket. le stands for less than or equal to, which means that the Histogram is cumulative. The +Inf bucket is always the same as the _count.

In PromQL rate() and histogram_quantile() can be used to calculate the quantile.