Due to a quirk (?) in linear histograms, if you want a histogram with a single bucket for each value in 1..N, you need to declare it: HISTOGRAM(NAME, 1, N, N+1, LINEAR, EXPLANATION) and not: HISTOGRAM(NAME, 1, N, N, LINEAR, EXPLANATION) because you need to account for the implicit zero bucket at the bottom. This has come up a couple times for new histograms, and at least GC_REASON seems to suffer from a wrong declaration. SSL telemetry was/is going to use histograms like this, too.
Created attachment 604111 [details] [diff] [review] patch The dead simple patch. Bikeshedding about the name welcome.
Histograms that could benefit from this macro: GC_REASON HTTP_*_DISPOSITION CACHE_*_SEARCH (odd to have a linear histogram for ms histogram, especially one so finely bucketed) CACHE_SERVICE_LOCK_WAIT* (same) PLACES_EXPIRATION_STEPS_TO_CLEAN DNS_LOOKUP_METHOD UPDATE_STATUS but most of those would involve a small tweak to the histogram (either in # of buckets or upper bound); doesn't seem worth the effort
Comment on attachment 604111 [details] [diff] [review] patch HISTOGRAM_SINGLE_VALUE_BUCKET is the best you can come up with? How about HISTOGRAM_CONTINUOUS?
HISTOGRAM_CONTINUOUS doesn't sound right. HISTOGRAM_ENUMERATED_VALUES (since most people seem to be sticking enums in these anyway)?
(In reply to Nathan Froyd (:froydnj) from comment #4) > HISTOGRAM_CONTINUOUS doesn't sound right. HISTOGRAM_ENUMERATED_VALUES > (since most people seem to be sticking enums in these anyway)? r+
Created attachment 606203 [details] [diff] [review] patch Use HISTOGRAM_ENUMERATED_VALUES. Adding r+ per Taras's earlier comment.
Autoland Patchset: Patches: 606203 Branch: mozilla-central => try Destination: http://hg.mozilla.org/try/pushloghtml?changeset=a9acecdb826d Try run started, revision a9acecdb826d. To cancel or monitor the job, see: https://tbpl.mozilla.org/?tree=Try&rev=a9acecdb826d
Try run for a9acecdb826d is complete. Detailed breakdown of the results available here: https://tbpl.mozilla.org/?tree=Try&rev=a9acecdb826d Results (out of 14 total builds): success: 14 Builds (or logs if builds failed) available at: http://firstname.lastname@example.org