Blog: why histograms?

[dyladan]

Guest post from https://dyladan.me/histograms/2023/05/02/why-histograms/

This is the first in a series of 3 posts. The second explains the differences and tradeoffs between histograms and summaries (https://dyladan.me/histograms/2023/05/03/histograms-vs-summaries/). The third explains exponential histograms in detail (https://dyladan.me/histograms/2023/05/04/exponential-histograms/).

Please feel free to share any editing or copy suggestions.

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Preview: https://deploy-preview-2658--opentelemetry.netlify.app/blog/2023/why-histograms/

[cartermp]

FYI - formatting check failed, but since we're probably going to do copy-edits, let's minimize your pain and only have you reformat stuff until after we're satisfied with the content 🙂

[dyladan]

FYI - formatting check failed, but since we're probably going to do copy-edits, let's minimize your pain and only have you reformat stuff until after we're satisfied with the content 🙂

It's just as easy to do it now. Reviews may be easier if things are in the expected format.

[cartermp]

Looks great overall, thank you! Mostly some small copy-edits, but I modified the last paragraph a a bit to caveat about backends and sampling strategies. Since accurate calculations of SLOs is a super deep topic we probably shouldn't elaborate too much, but I do think we should call out that the problems you can run into won't be the same from backend to backend.

[chalin]

See inline comments, thanks.

[dyladan]

updated the date to monday may 8th to reflect when this is likely to be merged

[dyladan]

If a maintainer merges this before that obviously they can change the date. I have enabled "allow edits from maintainers" on the PR

[dyladan]

@cartermp @chalin I rewrote the section "Other metric types" because on re-reading I noticed that the wording was technically incorrect. The last paragraph previously stated that collecting each percentile as a gauge is an ad-hoc implementation of histograms, when this is actually much closer to a summary metric type. I also added a caveat that summaries cannot be aggregated across hosts. PTAL

[cartermp]

Thanks! Great content. Unless there's no other objections, I'll merge this on Monday and it'll be live.

[chalin]

👍

[cartermp]

🎉