Manage Chromium histograms and enums metadata. Use this skill when adding code that logs a histogram or when updating metadata in histograms.xml or enums.xml.
This skill provides guidance and workflows for logging histograms and managing their metadata in the Chromium codebase.
When adding code that logs a histogram, you must also add metadata about that histogram and any associated enums to ensure they are properly tracked and interpreted.
histograms.xml.enums.xml in the same directory as
the corresponding histograms.xml.Metadata files are located in subdirectories of
//tools/metrics/histograms/metadata/. The subdirectory name is based on the
first part of the histogram name (e.g., Platform.Foo would likely be in
metadata/platform/). If the correct subdirectory is unclear, ask the user.
Histograms must have at least two owners:
Set the expiry date to 3 months in the future from the date you add the histogram, unless a specific date is more appropriate.
//tools/metrics/histograms/metadata/.<histogram> entry.<enum> and its <int> values are defined in enums.xml.//tools/metrics/histograms/README.md for additional
policies.