bug 1496789 - Document the limits for n_buckets and n_values r=Dexter
authorChris H-C <chutten@mozilla.com>
Wed, 17 Oct 2018 13:54:28 +0000
changeset 500135 02b768d81d9f727fa756d80a0ff0f7443f5dc143
parent 500134 1b32f9f0a5d33d4e6c1ef171b28bea4519100a2b
child 500136 55c7172f12a49ad69572ab2bad0d0ea76fa860ac
push id1864
push userffxbld-merge
push dateMon, 03 Dec 2018 15:51:40 +0000
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reviewersDexter
bugs1496789
milestone64.0a1
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bug 1496789 - Document the limits for n_buckets and n_values r=Dexter MozReview-Commit-ID: CxklgZ8VPyN Differential Revision: https://phabricator.services.mozilla.com/D8902
toolkit/components/telemetry/docs/collection/histograms.rst
--- a/toolkit/components/telemetry/docs/collection/histograms.rst
+++ b/toolkit/components/telemetry/docs/collection/histograms.rst
@@ -163,20 +163,28 @@ Optional, the default value is ``1``. Th
 ``high``
 --------
 Required for linear and exponential histograms. The maximum value to be stored in a linear or exponential histogram. Any recorded values greater than this maximum will be counted in the last bucket.
 
 ``n_buckets``
 -------------
 Required for linear and exponential histograms. The number of buckets in a linear or exponential histogram.
 
+.. note::
+
+    The maximum value for ``n_buckets`` is 100. The more buckets, the larger the storage and transfer costs borne by our users and our pipeline.
+
 ``n_values``
 ------------
 Required for enumerated histograms. Similar to n_buckets, it represent the number of elements in the enum.
 
+.. note::
+
+    The maximum value for ``n_values`` is 100. The more values, the larger the storage and transfer costs borne by our users and our pipeline.
+
 ``labels``
 ----------
 Required for categorical histograms. This is an array of strings which are the labels for different values in this histograms. The labels are restricted to a C++-friendly subset of characters (``^[a-z][a-z0-9_]+[a-z0-9]$``). This field is limited to 100 strings, each with a maximum length of 20 characters.
 
 ``bug_numbers``
 ---------------
 Required for all new histograms. This is an array of integers and should at least contain the bug number that added the probe and additionally other bug numbers that affected its behavior.