HDR is great for the use-case when you can bound your range beforehand and merging is not a requirement, but those were also the reasons we needed to develop DDSketch.
(1) HDR-Histogram merges are 100% accurate and very fast (few microseconds)
(2) The range of HDR-Histogram is bounded in the same way that floating point numbers are bounded. Hence the name "High Definition Range":
> For example, a Histogram could be configured to track the counts of observed integer values between 0 and 3,600,000,000,000 while maintaining a value precision of 3 significant digits across that range.
(1) HDR-Histogram merges are 100% accurate and very fast (few microseconds)
(2) The range of HDR-Histogram is bounded in the same way that floating point numbers are bounded. Hence the name "High Definition Range":
> For example, a Histogram could be configured to track the counts of observed integer values between 0 and 3,600,000,000,000 while maintaining a value precision of 3 significant digits across that range.
http://hdrhistogram.github.io/HdrHistogram/
Circllhist offers a default range of 10^-128 .. 10^+127, which has been more than ample for all use-cases I have seen.
https://github.com/circonus-labs/libcircllhist/blob/master/s...