tools/metrics/histograms/metadata/offline/histograms.xml

<!--
Copyright 2020 The Chromium Authors. All rights reserved.
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 comprehensive list of Offline histograms
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

Please follow the instructions in the OWNERS file in this directory to find a
reviewer. If no OWNERS file exists, please consider signing up at
go/reviewing-metrics (Googlers only), as all subdirectories are expected to
have an OWNERS file. As a last resort you can send the CL to
chromium-metrics-reviews@google.com.
-->

<histogram-configuration>

<histograms>

<histogram name="Offline.Measurements.HttpProbeResult"
    enum="OfflineMeasurementsHttpProbeResult" expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The result of the HTTP probe of the offline measurements experiment.

    Each time the Offline Measurements background task runs, one value is stored
    to prefs. At a later time, when Chrome is starting up, all stored results
    from past unreported HTTP probes are recorded to the histogram. The stored
    values are then cleared so they are only recorded once each.
  </summary>
</histogram>

<histogram name="Offline.Measurements.IsAirplaneModeEnabled"
    enum="BooleanEnabled" expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    Whether or not airplane mode was enabled when the Offline Measurements
    background task was run.

    Each time the Offline Measurements background task runs, the airplane mode
    status is queried, and then that value is stored to prefs. At a later time,
    when Chrome is starting up, all stored values are recorded to this
    histogram. The stored values are then cleared so they are only recorded once
    each.
  </summary>
</histogram>

<histogram name="Offline.Measurements.IsRoaming" enum="Boolean"
    expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    Whether or not the system was roaming when the Offline Measurements
    background task was run. If there are multiple networks, then if any network
    is not roaming, we record a value of &quot;not roaming&quot; (false).

    Each time the Offline Measurements background task runs, it queries all
    networks if they are marked roaming, and then that value is stored to prefs.
    At a later time, when Chrome is starting up, all stored values are recorded
    to this histogram. The stored values are then cleared so they are only
    recorded once each.
  </summary>
</histogram>

<histogram name="Offline.Measurements.MeasurementInterval" units="minutes"
    expires_after="2022-04-17">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The specified interval (in minutes) which the offline measurements
    experiment will periodically run. This value is logged when Chrome starts up
    for users where this feature is enabled.
  </summary>
</histogram>

<histogram name="Offline.Measurements.TimeBetweenChecks" units="minutes"
    expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The time (in minutes) between the last check and current check for the
    offline measurements experiment. This value is logged each time the offline
    measurements background task runs.
  </summary>
</histogram>

<histogram name="Offline.Measurements.UserState"
    enum="OfflineMeasurementsUserState" expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The state of the phone and how the user is interacting with it when the
    Offline Measurements background task runs.

    Each time the background task runs, it determines the user state, and then
    that value is stored to prefs. At a later time, when Chrome is starting up,
    all stored values are recorded to this histogram. The stored values are then
    cleared so they are only recorded once each.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ConnectivityChanged.DeviceState.Offline"
    enum="OfflineIndicatorSurfaceState" expires_after="2022-01-16">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <owner>sinansahin@google.com</owner>
  <owner>twellington@chromium.org</owner>
  <summary>
    For OfflineIndicatorV2, records whether the native browser controls can be
    animated and whether the omnibox is focused. Recorded when the device goes
    offline.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ConnectivityChanged.DeviceState.Online"
    enum="OfflineIndicatorSurfaceState" expires_after="2021-05-09">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <owner>sinansahin@google.com</owner>
  <owner>twellington@chromium.org</owner>
  <summary>
    For OfflineIndicatorV2, records whether the native browser controls can be
    animated and whether the omnibox is focused. Recorded when the device goes
    online.
  </summary>
</histogram>

<histogram name="OfflineIndicator.CTR" enum="OfflineIndicatorCTREvent"
    expires_after="2021-01-25">
  <owner>dimich@chromium.org</owner>
  <owner>jianli@chromium.org</owner>
  <summary>
    Records events related to click through rate (CTR) calculation for Offline
    Indicator UI. The CTR can be calculated by computing Clicked/Displayed.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDuration" units="ms"
    expires_after="2021-07-11">
  <obsolete>
    Removed M90. Replaced by OfflineIndicator.ShownDurationV2.
  </obsolete>
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <owner>sinansahin@google.com</owner>
  <owner>twellington@chromium.org</owner>
  <summary>
    The duration the offline indicator was shown. Recorded when the offline
    indicator hides.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDurationV2" units="ms"
    expires_after="2022-04-17">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The duration the offline indicator was shown. Recorded when the offline
    indicator stops being shown. There are two differences between this
    histogram and OfflineIndicator.ShownDuration: 1) the maximum bucket size and
    total number of buckets are higher in this histogram, and 2) this histogram
    is persisted in perfs. The second point means that if the user backgrounds
    then kills Chrome when the Offline Indicator was shown, then we will still
    record a sample. Note that in this case, when the user opens Chrome again
    and if the Offline Indicator is shown, then it will be treated as a
    continuation from before Chrome was killed.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDurationV2.InBackground" units="ms"
    expires_after="2021-12-05">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The duration the offline indicator was shown and Chrome was in the
    background. Samples are only recorded to this histogram if Chrome was in the
    background at some point while the offline indicator was shown. This is
    recorded when the offline indicator stops being shown. The data for this
    histogram is persisted in perfs, so if Chrome is killed, then we will still
    record a sample. Note that in this case, when the user opens Chrome again
    and the offline indicator is shown, then it will be treated as a
    continuation from before Chrome was killed.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDurationV2.InForeground" units="ms"
    expires_after="2021-12-05">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The duration the offline indicator was shown and Chrome was in the
    foreground. This is recorded every time the offline indicator stops being
    shown. The data for this histogram is persisted in perfs, so if Chrome is
    killed, then we will still record a sample. Note that in this case, when the
    user opens Chrome again and the offline indicator is shown, then it will be
    treated as a continuation from before Chrome was killed.
  </summary>
</histogram>

<histogram
    name="OfflineIndicator.ShownDurationV2.InForegroundWithoutBeingBackgrounded"
    units="ms" expires_after="2022-05-01">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The duration the offline indicator was shown and Chrome was in the
    foreground. Samples are only recorded to this histogram if Chrome was never
    in the background while the offline indicator was shown. This is recoreded
    when the offline indicator stops being shown. The data for this histogram is
    persisted in perfs, so if Chrome is killed, then we will still record a
    sample. Note that in this case, when the user opens Chrome again and the
    offline indicator is shown, then it will be treated as a continuation from
    before Chrome was killed.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDurationV2.NumTimesBackgrounded"
    units="times backgrounded" expires_after="2022-05-01">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The number of times Chrome was backgrounded while the offline indicator was
    shown. This is recorded every time the offline indicator stops being shown.
    The data for this histogram is persisted in perfs, so if Chrome is killed,
    then we will still record a sample. Note that in this case, when the user
    opens Chrome again and the offline indicator is shown, then it will be
    treated as a continuation from before Chrome was killed.
  </summary>
</histogram>

<histogram name="OfflineIndicator.ShownDurationV2.UntilFirstTimeBackgrounded"
    units="ms" expires_after="2021-12-05">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    The duration the offline indicator was first shown and in the foreground
    until Chrome was backgrounded. Samples are only recorded to this histogram
    if Chrome was in the background at some point while the offline indicator
    was shown. This is recoreded when the offline indicator stops being shown.
    The data for this histogram is persisted in perfs, so if Chrome is killed,
    then we will still record a sample. Note that in this case, when the user
    opens Chrome again and the offline indicator is shown, then it will be
    treated as a continuation from before Chrome was killed.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.AccessCount" units="units"
    expires_after="M85">
  <owner>jianli@chromium.org</owner>
  <summary>
    Number of accesses to the offline page since its creation. This is reported
    when the offline page was deleted.
  </summary>
</histogram>

<histogram name="OfflinePages.AccessEntryPoint"
    enum="OfflinePagesAccessEntryPoint" expires_after="2021-08-29">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Logs the UI location from which an offline page was launched.
  </summary>
</histogram>

<histogram name="OfflinePages.AccessPageCount"
    enum="OfflinePagesNamespaceEnumeration" expires_after="2022-06-26">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts the number of times an offline page is accessed. Events are reported
    per offline pages namespace.
  </summary>
</histogram>

<histogram name="OfflinePages.AggregatedRequestResult2"
    enum="OfflinePagesAggregatedRequestResult" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Result of servicing requests that may contain offline page.</summary>
</histogram>

<histogram name="OfflinePages.ArchiveManager.ArchiveDirsCreationResult2"
    enum="PlatformFileError" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    This is recorded every time the archive directory is being created. It
    doesn't include the case which the archive directory exists. It has suffixes
    indicating results for temporary or persistent archives directories.
  </summary>
</histogram>

<histogram name="OfflinePages.AutoFetch.CompleteNotificationAction"
    enum="OfflinePagesAutoFetchNotificationAction" expires_after="2021-10-04">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    This is recorded every time the auto-fetch complete notification is shown or
    interacted with.
  </summary>
</histogram>

<histogram name="OfflinePages.AutoFetch.InProgressNotificationAction"
    enum="OfflinePagesAutoFetchNotificationAction" expires_after="2021-10-04">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    This is recorded every time the auto-fetch in-progress notification is shown
    or interacted with.
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.EffectiveConnectionType.OffliningStartType"
    enum="NQEEffectiveConnectionType" expires_after="2021-06-25">
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Effective connection type at the start of an offlining attempt for an
    attempt that eventually failed.

    This metric is recorded for RequestCoordinator::SavePageLater API calls.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.EffectiveConnectionType.PauseRequests"
    enum="NQEEffectiveConnectionType" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Effective connection type when pausing one or more background loads is
    requested.

    This metric is recorded for RequestCoordinator::PauseRequests API calls.
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.EffectiveConnectionType.RemoveRequests"
    enum="NQEEffectiveConnectionType" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Effective connection type when removing one or more background loads is
    requested.

    This metric is recorded for RequestCoordinator::RemoveRequests API calls.
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.EffectiveConnectionType.ResumeRequests"
    enum="NQEEffectiveConnectionType" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Effective connection type when resuming one or more background loads is
    requested.

    This metric is recorded for RequestCoordinator::ResumeRequests API calls.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.EffectiveConnectionType.SavePageLater"
    enum="NQEEffectiveConnectionType" expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Effective connection type when a background load is requested.

    This metric is recorded for RequestCoordinator::SavePageLater API calls.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.FinalSavePageResult"
    enum="OfflinePagesBackgroundSavePageResult" expires_after="2021-06-25">
  <owner>chili@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Status code of background offlining requests at the final step.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.ImmediateStart.AvailableRequestCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests available for processing when
    processing starts immediately (vs. scheduled). This is for non-svelte
    devices (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ImmediateStart.AvailableRequestCount.Svelte"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests available for processing when
    processing starts immediately (vs. scheduled). This is for svelte devices
    (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ImmediateStart.UnavailableRequestCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests unavailable for processing when
    processing starts immediately (vs. scheduled). This is for non-svelte
    devices (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ImmediateStart.UnavailableRequestCount.Svelte"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests unavailable for processing when
    processing starts immediately (vs. scheduled). This is for svelte devices
    (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram name="OfflinePages.Background.ImmediateStartStatus"
    enum="OfflinePagesBackgroundImmediateStartStatus"
    expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Status of attempt to immediately start offlining a page in the background
    while application is still concurrently using the foreground. This may be
    attempted when an web page download is initially requested or resumed.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.LoadingErrorStatusCode"
    enum="CombinedHttpResponseAndNetErrorCode" expires_after="2021-06-25">
  <owner>chili@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The combined http and net error codes that caused a page load failure.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.OfflinerRequestStatus"
    enum="OfflinePagesBackgroundOfflinerRequestStatus"
    expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Status code of background offlining (loading and saving) requests.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.OffliningPreviewStatus"
    enum="BooleanEnabled" expires_after="2021-01-25">
  <obsolete>
    Removed 22 Jan 2021.
  </obsolete>
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Whether any previews were selected for a page we were asked to make
    available offline.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.RequestFailure.StartedAttemptCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of started attempts by failed background load requests.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.RequestSuccess.StartedAttemptCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of started attempts by successful background load requests.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.SavePageFromCCT" units="units"
    expires_after="2021-06-25">
  <owner>chili@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Whether the save page result came from chrome custom tabs.</summary>
</histogram>

<histogram name="OfflinePages.Background.ScheduledStart.AvailableRequestCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests available for processing when
    background scheduled processing starts. This is for non-svelte devices
    (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ScheduledStart.AvailableRequestCount.Svelte"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests available for processing when
    background scheduled processing starts. This is for svelte devices (where
    svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ScheduledStart.UnavailableRequestCount"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests unavailable for processing when
    background scheduled processing starts. This is for non-svelte devices
    (where svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram
    name="OfflinePages.Background.ScheduledStart.UnavailableRequestCount.Svelte"
    units="units" expires_after="2021-06-25">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of queued background load requests unavailable for processing when
    background scheduled processing starts. This is for svelte devices (where
    svelte is determined by base::SysInfo::IsLowEnd()).
  </summary>
</histogram>

<histogram name="OfflinePages.Background.TimeToCanceled" units="seconds"
    expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Time from background request until it was canceled.</summary>
</histogram>

<histogram name="OfflinePages.Background.TimeToSaved" units="seconds"
    expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time from background request until it was successfully saved.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.TimeToStart" units="ms"
    expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time from background request until processing it was first started. This is
    for non-svelte devices.
  </summary>
</histogram>

<histogram name="OfflinePages.Background.TimeToStart.Svelte" units="ms"
    expires_after="2021-03-01">
  <owner>dougarnett@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time from background request until processing it was first started on svelte
    device. Svelte is determined by base::SysInfo::IsLowEnd().
  </summary>
</histogram>

<histogram name="OfflinePages.CleanupThumbnails.Count" units="thumbnails"
    expires_after="2021-06-25">
  <owner>harringtond@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Number of thumbnails removed by the thumbnail cleanup task.</summary>
</histogram>

<histogram name="OfflinePages.ClearStoragePreRunUsage2" units="KiB"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The total disk storage size used by all offline pages from a specific client
    namespace.
  </summary>
</histogram>

<histogram name="OfflinePages.ClearTemporaryPages.BatchSize" units="pages"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of pages deleted in a batch in one clear storage task.
  </summary>
</histogram>

<histogram name="OfflinePages.ClearTemporaryPages.Result"
    enum="OfflinePagesClearStorageResult" expires_after="2021-06-25">
  <owner>romax@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Result of clearing temporary pages to release storage space.
  </summary>
</histogram>

<histogram name="OfflinePages.ClearTemporaryPages.TimeSinceCreation"
    units="minutes" expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    When a temporary page is deleted due to storage pressure, reports the time
    since its creation. This metric should be useful to track the occurrence of
    &quot;content thrashing&quot;, when automatically created temporary pages
    are forcing the deletion of recently saved temporary pages.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Legacy.DeletedHeadlessFileCount"
    units="files" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of files which are deleted during legacy dir clearing since they have
    no associated DB entry and live in private directory.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Persistent.ExpiredEntryCount"
    units="entries" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of DB entries (in persistent namespaces) that have been missing their
    files for longer than 365 days, and deleted during maintenance task.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Persistent.MissingFileCount"
    units="files" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of files that are found missing during maintenance task, which is
    also the number of DB entries that are updated with valid file missing time.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Persistent.ReappearedFileCount"
    units="files" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of files that were marked as missing reappeared in the file system,
    which is also the number of DB entries that removes file missing time.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Persistent.Result"
    enum="OfflinePagesSyncOperationResult" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Result of persistent page consistency check.</summary>
</histogram>

<histogram
    name="OfflinePages.ConsistencyCheck.Temporary.PagesMissingArchiveFileCount"
    units="pages" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of temporary offline pages without archive file when checking
    consistency. It will only be reported if the number is larger than 0.
  </summary>
</histogram>

<histogram
    name="OfflinePages.ConsistencyCheck.Temporary.PagesMissingDbEntryCount"
    units="pages" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of archives without database entry when checking temporary page
    consistency. It will only be reported if the number is larger than 0.
  </summary>
</histogram>

<histogram name="OfflinePages.ConsistencyCheck.Temporary.Result"
    enum="OfflinePagesSyncOperationResult" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Result of temporary page consistency check.</summary>
</histogram>

<histogram name="OfflinePages.DeletePageCount"
    enum="OfflinePagesNamespaceEnumeration" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts the number of times an offline page is deleted. Events are reported
    per offline pages namespace.
  </summary>
</histogram>

<histogram name="OfflinePages.DeletePageResult"
    enum="OfflinePagesDeletePageResult" expires_after="2021-06-25">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Result of removing an offline copy for a page.</summary>
</histogram>

<histogram name="OfflinePages.DidNavigationThrottleCancelNavigation"
    enum="Boolean" expires_after="2022-06-19">
  <owner>curranmax@chromium.org</owner>
  <owner>tbansal@chromium.org</owner>
  <summary>
    Whether or not the OfflinePageNavigationThrottle canceled a navigation
    request. Requests are only canceled if and only if the navigation request
    was initiated by the renderer and the request headers contain the
    &quot;X-Chrome-offline&quot; header.

    This histogram is recorded each time Chrome tries to create an
    OfflinePageNavigationThrottle, which only happens on Android (since Offline
    Pages is only enabled there).
  </summary>
</histogram>

<histogram name="OfflinePages.DownloadRequestTimeSinceDuplicateRequested"
    units="seconds" expires_after="2021-11-07">
  <owner>dewittj@chromium.org</owner>
  <owner>fgorski@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    If at request time there is another request with the same URL, this tracks
    this amount of time between creation of the most recent request and the
    current request.
  </summary>
</histogram>

<histogram name="OfflinePages.DownloadRequestTimeSinceDuplicateSaved"
    units="seconds" expires_after="2021-06-25">
  <owner>dewittj@chromium.org</owner>
  <owner>fgorski@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    If at request time there is another downloaded page with the same URL, this
    tracks this amount of time between creation of the most recent existing page
    and the current request.
  </summary>
</histogram>

<histogram name="OfflinePages.DownloadUI.PrefetchedItemHasThumbnail"
    enum="BooleanAvailable" expires_after="2021-06-25">
  <owner>harringtond@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Whether or not a thumbnail was provided for a prefetched offline article.
    Recorded when the item is shown in Downloads Home.
  </summary>
</histogram>

<histogram name="OfflinePages.LastN.IsSavingSamePage"
    enum="OfflinePagesLastNIsSavingSamePageEnum" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Upon starting saving a new last_n offline page snapshot, report if that is
    being done for a page that is new (a navigation happened) or for one that
    has been previously saved in the same session (no navigation happened). This
    metric will assist in determining if there is the need to better track
    actual content changes in pages saved more than once by last_n.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.MhtmlLoadResult"
    enum="MhtmlLoadResult" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Result of an attempt to load an MHTML archive to display a trusted offline
    page, recorded per offline namespace by OfflinePageTabHelper after renderer
    attempts to load the archive.
  </summary>
</histogram>

<histogram name="OfflinePages.MhtmlLoadResultUntrusted" enum="MhtmlLoadResult"
    expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Result of an attempt to load an MHTML archive to display an untrusted
    offline page, recorded by OfflinePageTabHelper after the renderer attempts
    to load the archive.
  </summary>
</histogram>

<histogram name="OfflinePages.OfflineUsage" enum="OfflinePagesOfflineUsage"
    expires_after="2022-07-11">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts user-days when Chrome was used in specific ways regarding navigation
    to online and offline content. Buckets are mutually exclusive so that only
    one bucket is incremented per reported day. This metric is not recorded to
    UMA immediately due to potential data loss while offline. So day counters
    are persisted to prefs and reported to the histogram only when the next UMA
    data upload is likely to succeed. For more details see:
    https://goo.gl/GJXwFe.
  </summary>
</histogram>

<histogram name="OfflinePages.OfflineUsage.NotOfflineResilient"
    enum="OfflinePagesOfflineUsage" expires_after="2022-04-17">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts user-days when Chrome was used in specific ways regarding navigation
    to online and offline content. Buckets are mutually exclusive so that only
    one bucket is incremented per reported day.

    This metric is a mirror of OfflinePages.OfflineUsage but it doesn't use any
    of the offline resilient mechanisms that one has. Ideally both should report
    exactly the same values but it is expected this one will lose more samples.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.PageAccessInterval" units="minutes"
    expires_after="2021-08-29">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Length of time between accesses to an offline page. This is the same time
    period used for expiring temporary pages. This metric is recorded when an
    offline page is accessed.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.PageLifetime" units="minutes"
    expires_after="2021-06-25">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Length of time between when an offline page was created and was removed.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.PageSize" units="KB"
    expires_after="2021-06-25">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Size of the saved copy of an offline page.</summary>
</histogram>

<histogram name="OfflinePages.PageSizeOnAccess.Offline" units="KiB"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Records the archive size of an offline page loaded during a navigation that
    took place while the device was considered to be offline or with poor
    connectivity.
  </summary>
</histogram>

<histogram name="OfflinePages.PageSizeOnAccess.Online" units="KiB"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Records the archive size of an offline page loaded during a navigation that
    took place while the device was considered to be online.
  </summary>
</histogram>

<histogram name="OfflinePages.PrefetchEnabled" enum="BooleanEnabled"
    expires_after="2021-10-31">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts user-days when candidate articles were suggested to the Offline
    Prefetch pipeline while it was enabled. This metric is not recorded to UMA
    immediately due to potential data loss while offline. So day counters are
    persisted to prefs and reported to the histogram only when the next UMA data
    upload is likely to succeed. For more details see: https://goo.gl/GJXwFe.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.ActionAttempts" units="attempts"
    expires_after="2021-06-25">
  <owner>dewittj@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Number of attempts to perform a specific retriable pipeline action for each
    finished prefetch item.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.DownloadedFileSize" units="KiB"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Actual size of archive file successfully downloaded by offline page
    prefetching.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.DownloadExpectedFileSize" units="KiB"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Expected download size of archive file, after gzip content encoding, that
    started being downloaded by offline page prefetching. Sizes reported in this
    metric are less than the sizes reported in DownloadedFileSize due to content
    gzip encoding.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.DownloadFinishedUpdate"
    enum="OfflinePrefetchDownloadFinishedOutcome" expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Reports the possible outcomes of an archive download finishing and its
    respective prefetch item being updated in the store. Downloads are expected
    to succeed or fail but a respective item should always exist and be updated.
    The &quot;item not found&quot; cases are exceptions.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.FinishedItemErrorCode"
    enum="OfflinePrefetchItemErrorCode" expires_after="2022-05-08">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Error code representing the reason why each offline prefetch item was
    finalized.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.ItemLifetime" units="seconds"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The lifetime of an offline prefetch item, from creation until
    &quot;zombie-fication&quot; (after metrics collection).
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.NotificationAction"
    enum="OfflinePagePrefetchNotificationAction" expires_after="2021-08-29">
  <owner>dewittj@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Actions taken with respect to the offline prefetch notification, includes
    show attempts to calculate CTR.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.OfflinePageImportResult"
    enum="OfflinePrefetchPageImportResult" expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Final result of an attempt to import a prefetched article into the Offline
    Pages system.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.ServiceGetOperationStatus"
    enum="OfflinePrefetchRequestStatus" expires_after="2021-06-25">
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Status returned by a request to the Offline Page Service's GetOperation
    method.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.ServiceGetPageBundleStatus"
    enum="OfflinePrefetchRequestStatus" expires_after="2021-06-25">
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Status returned by a request to the Offline Page Service's GetPageBundle
    method.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.StateCounts"
    enum="OfflinePrefetchItemState" expires_after="2021-06-25">
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    A prefetch item was seen in this state when starting the background task.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.StuckItemState"
    enum="OfflinePrefetchItemState" expires_after="2021-06-25">
  <owner>petewil@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    A prefetch item was found in this state after more than 7 days since its
    creation, time enough for it to have been finalized by the pipeline.
  </summary>
</histogram>

<histogram name="OfflinePages.Prefetching.UniqueUrlsAddedCount" units="urls"
    expires_after="2021-08-29">
  <owner>dewittj@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    When receiving suggestions in the prefetch pipeline, emits the number of new
    suggestions added to the database. If there is an error, nothing is emitted.
  </summary>
</histogram>

<histogram name="OfflinePages.PrefetchStore.StoreEvent"
    enum="OfflinePagesStoreEvent" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts when the offline pages prefetch store is opened or closed.
  </summary>
</histogram>

<histogram name="OfflinePages.PrefetchUsage" enum="OfflinePagesPrefetchUsage"
    expires_after="2022-07-03">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Counts user-days categorized by how Offline Prefetch performed and had its
    content accessed by the user. Buckets are mutually exclusive so that only
    one bucket is incremented per reported day. This metric is not recorded to
    UMA immediately due to potential data loss while offline. So day counters
    are persisted to prefs and reported to the histogram only when the next UMA
    data upload is likely to succeed. For more details see:
    https://goo.gl/GJXwFe.
  </summary>
</histogram>

<histogram name="OfflinePages.PublishArchive.PublishSource"
    enum="OfflinePagesPublishSource" expires_after="M85">
  <owner>petewil@chromium.org</owner>
  <summary>
    When publishing an offline page, a page might not be found. This returns the
    publishing path that was used (ex: by Guid or by OfflineId).
  </summary>
</histogram>

<histogram name="OfflinePages.SavedPageCountUponQuery" units="pages"
    expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Total number of saved offline pages recorded when they are all queried from
    the store. This value is more meaningful when filtered by unique users as
    that eliminates multiple reports from the same Chrome instance.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePage.AddPageTime" units="ms"
    expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time taken to successfully create the store metadata entry for an offline
    page archive during the process of saving an offline page.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePage.ComputeDigestTime"
    units="ms" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time taken to successfully compute the digest of an offline page archive
    during the process of saving an offline page.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePage.CreateArchiveTime"
    units="ms" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time taken to successfully create an offline page archive during the process
    of saving an offline page.
  </summary>
</histogram>

<histogram name="OfflinePages.SavePage.PercentLoaded" units="%"
    expires_after="M77">
  <owner>twellington@chromium.org</owner>
  <owner>ianwen@chromium.org</owner>
  <summary>
    The percentage of the page load completed when the button to save an offline
    page is pressed.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePage.PublishArchiveTime"
    units="ms" expires_after="2021-05-31">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Time taken to successfully move an offline page archive to the public
    downloads folder during the process of saving an offline page.
  </summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePageResult2"
    enum="OfflinePagesSavePageResult" expires_after="M85">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Result of saving an offline copy for a page.</summary>
</histogram>

<histogram base="true" name="OfflinePages.SavePageTime" units="ms"
    expires_after="2021-06-25">
  <owner>jianli@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The amount of time taken to save an offline copy for a page.
  </summary>
</histogram>

<histogram name="OfflinePages.SharedPageWasOffline"
    enum="OfflinePagesSharedPageWasOffline" expires_after="2021-06-25">
  <owner>dewittj@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>Whether a shared page was an offline page or not.</summary>
</histogram>

<histogram name="OfflinePages.Sharing.PublishInternalPageResult"
    enum="OfflinePagesSavePageResult" expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Result of publishing internal page while sharing. CANCELLED means the page
    to publish isn't found. ALREADY_EXISTS means the page have already been
    published before.
  </summary>
</histogram>

<histogram name="OfflinePages.SQLStorage.StoreEvent"
    enum="OfflinePagesStoreEvent" expires_after="2021-06-25">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Used as a counter to track different events related to offline page store
    inner working.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.ExternalArchiveSizeMiB" units="MiB"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The storage space used by the archive files of offline pages, including all
    files in public directory with mhtml/mht extensions. Collected after every
    time an offline page is saved successfully.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.ExternalFreeSpaceMiB" units="MiB"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The amount of free space on the external drive (which contains the public
    download directory). Collected after every time an offline page is saved
    successfully.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.ExternalUsagePercentage" units="%"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The percentage of storage space on the external volume (that contains public
    download directory) used by offline pages archives.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.InternalArchiveSizeMiB" units="MiB"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The storage space used by the archive files of offline pages, including the
    files in temporary and private directory. Collected after every time an
    offline page is saved successfully.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.InternalFreeSpaceMiB" units="MiB"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The amount of free space on the internal drive (which contains the app
    directory). Collected after every time an offline page is saved
    successfully.
  </summary>
</histogram>

<histogram name="OfflinePages.StorageInfo.InternalUsagePercentage" units="%"
    expires_after="2021-06-25">
  <owner>dimich@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The percentage of storage space on internal volume (that contains the app
    directory) used by offline pages archives.
  </summary>
</histogram>

<histogram name="OfflinePages.TabRestore" enum="OfflinePagesTabRestoreType"
    expires_after="2021-06-25">
  <owner>carlosk@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    Tracks the reload of contents of an existing tab that is being restored
    either because that tab is being presented for the first time after Chrome
    was restarted or because its contents were discarded. All buckets are
    mutually exclusive (adding up all reported values amounts to the total
    number of tracked tab restores). This metric is focused on last_n offline
    pages and is exclusive to Chrome on Android.
  </summary>
</histogram>

<histogram name="OfflinePages.TrustStateOnOpen" enum="OfflinePageTrustedState"
    expires_after="2021-06-25">
  <owner>sclittle@chromium.org</owner>
  <owner>offline-dev@chromium.org</owner>
  <summary>
    The trust state of the offline page. This is recorded when an offline page
    is being opened.
  </summary>
</histogram>

<histogram name="OfflinePages.WebsiteSettings.OpenOnlineButtonVisible"
    enum="BooleanVisible" expires_after="M77">
  <owner>fgorski@chromium.org</owner>
  <summary>
    Indicates whether Open online was visible in Page Info popup, when it was
    shown for an offline page. (The button is visible only when Chrome is
    connected when the Page Info popup is opened for offline page.)
  </summary>
</histogram>

</histograms>

</histogram-configuration>