<!--
Copyright 2021 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<!--
This file is used to generate a list of histograms for the privacy
budget project along with a detailed description for each histogram.

For best practices on writing histogram descriptions, see
https://chromium.googlesource.com/chromium/src.git/+/HEAD/tools/metrics/histograms/README.md
-->

<histogram-configuration>

<histograms>

<histogram name="PrivacyBudget.ClockDrift.FetchLatencyVariance" units="ms^2"
    expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the variance of the latencies of clock skew samples used for the
    computation of the clock drift. Only recorded for background fetches, which
    are enabled only via a feature parameter (and disabled by default), and only
    recorded if clock drift is enabled via its feature parameter.
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockDrift.Magnitude.Negative"
    units="microseconds/s" expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the absolute value of the computed clock drift (time derivative of
    clock skew), when negative. Only recorded for background fetches, which are
    enabled only via a feature parameter (and disabled by default), and only
    recorded if clock drift is enabled via its feature parameter.
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockDrift.Magnitude.Positive"
    units="microseconds/s" expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the absolute value of the computed clock drift (time derivative of
    clock skew), when positive. Only recorded for background fetches, which are
    enabled only via a feature parameter (and disabled by default), and only
    recorded if clock drift is enabled via its feature parameter.
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockSkew.FetchLatency" units="ms"
    expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the duration of the network round-trip performed to fetch the time
    from the network server. Only recorded for background fetches, which are
    enabled only via a feature parameter (and disabled by default).
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockSkew.FetchLatencyJitter" units="ms"
    expires_after="2024-03-24">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the standard deviation of the last three fetch latencies (i.e. the
    durations of the last three network round-trip performed to fetch the time
    from the network server). Only recorded for background fetches, which are
    enabled only via a feature parameter (and disabled by default).
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockSkew.Magnitude.Negative" units="ms"
    expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the absolute value of the computed clock skew (local clock - remote
    clock), when negative. Only recorded for background fetches, which are
    enabled only via a feature parameter (and disabled by default).
  </summary>
</histogram>

<histogram name="PrivacyBudget.ClockSkew.Magnitude.Positive" units="ms"
    expires_after="2024-03-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>areimers@chromium.org</owner>
  <summary>
    Records the computed clock skew (local clock - remote clock), when positive.
    Only recorded for background fetches, which are enabled only via a feature
    parameter (and disabled by default).
  </summary>
</histogram>

<histogram name="PrivacyBudget.Identifiability.FinchConfigValidationResult"
    enum="BooleanSuccess" expires_after="2024-02-04">
  <owner>antoniosartori@chromium.org</owner>
  <owner>mkwst@chromium.org</owner>
  <summary>
    Indicates whether the Finch configuration for the privacy budget
    identifiability study was validated successfully.
  </summary>
</histogram>

<histogram name="PrivacyBudget.Identifiability.RecordedSample"
    enum="PrivacyBudgetRecordedSample" expires_after="2024-05-17">
  <owner>antoniosartori@chromium.org</owner>
  <owner>mkwst@chromium.org</owner>
  <summary>
    Indicates whether a sample collected in the renderer was accepted or dropped
    by the AggregatingSampleCollector.
  </summary>
</histogram>

</histograms>

</histogram-configuration>
