tools/metrics/histograms/histograms_xml/service/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 Service 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 send CLs to chromium-metrics-reviews@google.com rather than to specific
individuals. These CLs will be automatically reassigned to a reviewer within
about 5 minutes. This approach helps the metrics team to load-balance incoming
reviews. Googlers can read more about this at go/gwsq-gerrit.
-->

<histogram-configuration>

<histograms>

<histogram name="ServiceWorker.AbortPaymentEvent.Time" units="ms"
    expires_after="2021-08-01">
  <owner>danyao@chromium.org</owner>
  <owner>web-payments-team@google.com</owner>
  <owner>jinho.bang@samsung.com</owner>
  <summary>
    The time taken between dispatching an AbortPaymentEvent to a Service Worker
    and receiving a message that it finished handling the event. Includes the
    time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.ActivateEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    Execution time of ServiceWorkerGlobalScope.onactivate. Includes the time for
    waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.ActivateEventStatus"
    enum="ServiceWorkerStatusCode" expires_after="2021-06-18">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of dispatching the activate event to the worker. This is recorded
    to both ServiceWorker.ActivateEventStatus and whichever of
    ServiceWorker.ActivateEventStatus_InShutdown
    ServiceWorker.ActivateEventStatus_NotInShutdown is appropriate. (InShutdown
    means the context was null or ServiceWorkerProcessManger::Shutdown was
    called.)
  </summary>
</histogram>

<histogram name="ServiceWorker.BackgroundFetchAbortEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nator@chromium.org</owner>
  <owner>peter@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <summary>
    The time taken between dispatching a BackgroundFetchAbortEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.BackgroundFetchClickEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nator@chromium.org</owner>
  <owner>peter@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <summary>
    The time taken between dispatching a BackgroundFetchClickEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.BackgroundFetchFailEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nator@chromium.org</owner>
  <owner>peter@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <summary>
    The time taken between dispatching a BackgroundFetchFailEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.BackgroundFetchSuccessEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nator@chromium.org</owner>
  <owner>peter@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <summary>
    The time taken between dispatching a BackgroundFetchSuccessEvent to a
    Service Worker and receiving a message that it finished handling the event.
    Includes the time for the waitUntil() promise to settle. This event is sent
    when the background fetch succeeds.
  </summary>
</histogram>

<histogram name="ServiceWorker.BackgroundSyncEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nator@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <summary>
    The time taken between dispatching a SyncEvent to a Service Worker and
    receiving a message that it finished handling the event. Includes the time
    for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.CacheStorageInstalledScript.CachedMetadataSize"
    units="bytes" expires_after="2021-06-08">
  <owner>horo@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <summary>
    The length of cached metadata of scripts which are stored to the
    CacheStorage by the installing service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.CacheStorageInstalledScript.CachedMetadataTotalSize"
    units="bytes" expires_after="2021-06-08">
  <owner>horo@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <summary>
    The total length of cached metadata of scripts which are stored to the
    CacheStorage by the installing service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.CacheStorageInstalledScript.Count" units="count"
    expires_after="2021-06-08">
  <owner>horo@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <summary>
    The counts of scripts which are stored to the CacheStorage by the installing
    service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.CacheStorageInstalledScript.ScriptSize"
    units="bytes" expires_after="2021-06-08">
  <owner>horo@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <summary>
    The length of scripts which are stored to the CacheStorage by the installing
    service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.CacheStorageInstalledScript.ScriptTotalSize"
    units="bytes" expires_after="2021-06-08">
  <owner>horo@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <summary>
    The total length of scripts which are stored to the CacheStorage by the
    installing service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.CanMakePaymentEvent.Time" units="ms"
    expires_after="2021-08-01">
  <owner>danyao@chromium.org</owner>
  <owner>web-payments-team@google.com</owner>
  <owner>jinho.bang@samsung.com</owner>
  <summary>
    The time taken between dispatching an CanMakePaymentEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.ContentDeleteEvent.Time" units="ms"
    expires_after="M92">
  <owner>rayankans@chromium.org</owner>
  <owner>platform-capabilities@chromium.org</owner>
  <summary>
    The time taken between dispatching a ContentDeleteEvent to a Service Worker
    and receiving a message that it finished handling the event. Includes the
    time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.CookieChangeEvent.Time" units="ms"
    expires_after="M85">
  <owner>pwnall@chromium.org</owner>
  <summary>
    The time taken between dispatching a CookieChangeEvent to a Service Worker
    and receiving a message that it finished handling the event. Includes the
    time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.Database.DestroyDatabaseResult"
    enum="ServiceWorkerDatabaseStatus" expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of destroy database operations in ServiceWorkerDatabase.
  </summary>
</histogram>

<histogram name="ServiceWorker.Database.OpenResult"
    enum="ServiceWorkerDatabaseStatus" expires_after="never">
<!-- expires-never: core storage metric; consumed in separate dashboard (go/chrome-storage-dashboard) -->

  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of opening a database for ServiceWorkerDatabase.
  </summary>
</histogram>

<histogram name="ServiceWorker.Database.ReadResult"
    enum="ServiceWorkerDatabaseStatus" expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>Records result of read operations in ServiceWorkerDatabase.</summary>
</histogram>

<histogram name="ServiceWorker.Database.WriteResult"
    enum="ServiceWorkerDatabaseStatus" expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of write operations in ServiceWorkerDatabase.
  </summary>
</histogram>

<histogram name="ServiceWorker.DiskCache.InitResult" units="units"
    expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of opening a disk cache for ServiceWorkerDiskCache.
  </summary>
</histogram>

<histogram name="ServiceWorker.DiskCache.ReadResponseResult"
    enum="ServiceWorkerReadResponseResult" expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of reading response from ServiceWorkerDiskCache.
  </summary>
</histogram>

<histogram name="ServiceWorker.DiskCache.WriteResponseResult"
    enum="ServiceWorkerWriteResponseResult" expires_after="2021-05-18">
  <owner>bashi@chromium.org</owner>
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records result of writing response into ServiceWorkerDiskCache. This is not
    recorded when response has no body. Note that this is recorded on every
    write operation, and can there can be multiple write operations for the same
    response if it is large enough.
  </summary>
</histogram>

<histogram name="ServiceWorker.EmbeddedWorkerInstanceClient.StartWorker"
    enum="ServiceWorkerRendererStartWorker" expires_after="M81">
  <owner>panicker@chromium.org</owner>
  <summary>
    Records when StartWorker is received on the renderer. This is used to
    surface discrepancy between StartWorker being sent on the browser side and
    not getting received by renderer.
    EmbeddedWorkerInstance.Start.TimeToSendStartWorker should be used as a
    baseline. TODO(panicker): This should be removed after investigation of
    crbug/790903, potentially in M68.
  </summary>
</histogram>

<histogram name="ServiceWorker.ExtendableMessageEvent.Time" units="ms"
    expires_after="2021-06-30">
  <owner>nhiroki@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken between dispatching an ExtendableMessageEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.ExternalRequest.Time" units="ms"
    expires_after="M85">
  <owner>lazyboy@chromium.org</owner>
  <summary>
    The duration an external request spent to keep a service worker alive.
    Currently, extension service workers use external requests to keep the
    worker alive during the time the worker requests an extension API.
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.Fallback.Time" units="ms"
    expires_after="2021-05-23">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken between dispatching a FetchEvent to a Service Worker and
    receiving a fallback-to-network reply.
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.HasResponse.Time" units="ms"
    expires_after="2021-06-06">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken between dispatching a FetchEvent to a Service Worker and
    receiving a response. Includes the time for the respondWith() promise to
    settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.MainResource.Status"
    enum="ServiceWorkerStatusCode" expires_after="2021-06-20">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of dispatching a fetch event to a Service Worker for a main
    resource request (i.e., a request for a navigation or a shared worker).
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.QueuingTime" units="ms"
    expires_after="2021-06-01">
  <owner>asamidoi@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time that a fetch event was queued. The start time is when the event is
    created on the service worker thread and added to the
    ServiceWorkerEventQueue. The end time is when the event is dequeued and the
    event handler starts to execute.
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.Subresource.Status"
    enum="ServiceWorkerStatusCode" expires_after="2021-06-20">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of dispatching a fetch event to a Service Worker for a
    subresource request (i.e., not a navigation or a shared worker request).
  </summary>
</histogram>

<histogram name="ServiceWorker.FetchEvent.WaitUntil.Time" units="ms"
    expires_after="2021-06-30">
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken between dispatching a FetchEvent to a Service Worker and
    finishing the FetchEvent. Includes the time for the waitUntil() promise to
    settle. If there is no waitUntil promise, this will be almost the same with
    HasResponse.Time or Fallback.Time.
  </summary>
</histogram>

<histogram name="ServiceWorker.GetAllOriginsInfoTime" units="ms"
    expires_after="2021-01-24">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    Execution time of ServiceWorkerContextWrapper::GetAllOriginsInfo().
  </summary>
</histogram>

<histogram name="ServiceWorker.InstallEvent.All.FetchCount" units="fetches"
    expires_after="2021-10-01">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The number of network fetches performed by the install event handler.
  </summary>
</histogram>

<histogram name="ServiceWorker.InstallEvent.{type}.Status"
    enum="ServiceWorkerStatusCode" expires_after="2021-04-06">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of dispatching the install event to the worker. This histogram
    includes data for ${type}.
  </summary>
  <token key="type">
    <variant name="All" summary="all install events"/>
    <variant name="WithFetch"
        summary="install events that made network fetches"/>
  </token>
</histogram>

<histogram name="ServiceWorker.InstallEvent.{type}.Time" units="ms"
    expires_after="2021-04-06">
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken between dispatching an InstallEvent to a Service Worker and
    receiving a message that it finished handling the event. Includes the time
    for the waitUntil() promise to settle. This histogram includes data for
    ${type}.
  </summary>
  <token key="type">
    <variant name="All" summary="all install events"/>
    <variant name="WithFetch"
        summary="install events that made network fetches"/>
  </token>
</histogram>

<histogram name="ServiceWorker.InternalsPageAccessed"
    enum="ServiceWorkerInternalsLinkQuery" expires_after="M90">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The method that the user takes to arrive at
    chrome://serviceworker-internals, based on the query string. Specifically,
    it logs if a user accessed it through the DevTools link in the Application
    Panel, or not.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.FetchHandlerEndToFallbackNetwork"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) renderer process sends an IPC message to notify that
    a resource loading request needs to be fall back to network, to (b) browser
    process received the IPC. Recorded when no fetch event handler provided a
    response to the request.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.FetchHandlerEndToResponseReceived"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) renderer process sends an IPC message to notify that
    a promise of respondWith() is settled, to (b) browser process received the
    IPC message. Recorded when a fetch event handler handled the request and
    provided a response to the request.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.FetchHandlerStartToFetchHandlerEnd"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) a fetch event is dispatched, to (b) respondWith() is
    settled for the fetch event, or fetch event dispatch is finished without
    respondWith() being called.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.ForwardServiceWorkerToWorkerReady2"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) a resource loading request is routed to service
    worker path, to (b) a service worker is ready to handle the request.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.ResponseReceivedToCompleted2"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) response headers from service worker are received,
    to (b) reading response body is completed. Recorded when a fetch event
    handler handled the request.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.StartToForwardServiceWorker"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) the start of a navigation request, to (b) the
    request is forwarded to a service worker code path. This includes looking up
    a service worker registration and throttling.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.MainFrame.MainResource.WorkerReadyToFetchHandlerStart"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) browser process sends an IPC message to dispatch a
    fetch event, to (b) a renderer process received the IPC message and is about
    to dispatch a fetch event.

    Recorded for each navigation request (including redirects) where there is a
    fetch event handler and the fetch event was successfully dispatched to the
    service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.Subresource.FetchHandlerEndToFallbackNetwork"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) service worker sends a mojo message to notify that a
    resource loading request needs to be fall back to network, to (b) the mojo
    message is received on the other side of mojo endpoint (a background thread
    executing subresource loading). Recorded when no fetch event handler
    provided a response to the request.

    Recorded for each subresource request where there is a fetch event handler
    and the fetch event was successfully dispatched to the service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.Subresource.FetchHandlerEndToResponseReceived"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) service worker sends a mojo message to notify that a
    promise of respondWith() is settled, to (b) the mojo message is received on
    the other side of mojo endpoint (a background thread executing subresource
    loading). Recorded when a fetch event handler handled the request and
    provided a response to the request.

    Recorded for each subresource request where there is a fetch event handler
    and the fetch event was successfully dispatched to the service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.Subresource.ForwardServiceWorkerToWorkerReady"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) a subresource request is routed to the URLLoader (on
    a background thread) for service worker controlled loads starts handling a
    subresource request, to (b) a service worker is ready to handle the request.

    Recorded for each subresource request where there is a fetch event handler
    and the fetch event was successfully dispatched to the service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.Subresource.ResponseReceivedToCompleted2"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) response headers from service worker are received,
    to (b) reading response body is completed. Only recorded when a fetch event
    handler handled the request.

    Recorded for each subresource request where there is a fetch event handler
    and the fetch event was successfully dispatched to the service worker.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.LoadTiming.Subresource.WorkerReadyToFetchHandlerEnd"
    units="ms" expires_after="2021-10-31">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) a fetch event is dispatched, to (b) respondWith() is
    settled for the fetch event, or fetch event dispatch is finished without
    respondWith() being called.

    Recorded for each subresource request where there is a fetch event handler
    and the fetch event was successfully dispatched to the service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.LookupRegistration.MainResource.Time" units="ms"
    expires_after="2021-10-31">
  <owner>shimazu@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken from (a) a resource loading request is routed to service
    worker path, to (b) existance of a registered service worker is looked up.
    This metric only cares about looking up a registration for navigation. This
    doesn't include look-ups for updating a service worker.

    Please refer to the suffixed histograms for each of the cases where a
    registration is found, not found, and an error happens.
  </summary>
</histogram>

<histogram name="ServiceWorker.MainFramePageLoad" enum="ServiceWorkerSite"
    expires_after="2021-06-13">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    Counts main frame page loads controlled by a service worker.
  </summary>
</histogram>

<histogram name="ServiceWorker.NotificationClickEvent.Time" units="ms"
    expires_after="M90">
  <owner>peter@chromium.org</owner>
  <owner>knollr@chromium.org</owner>
  <summary>
    The time taken between dispatching a NotificationClickEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.NotificationCloseEvent.Time" units="ms"
    expires_after="M90">
  <owner>nsatragno@chromium.org</owner>
  <owner>peter@chromium.org</owner>
  <summary>
    The time taken between dispatching a NotificationCloseEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.PageLoad" enum="ServiceWorkerSite"
    expires_after="2021-06-20">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>Counts page loads controlled by a service worker.</summary>
</histogram>

<histogram name="ServiceWorker.PaymentRequestEvent.Time" units="ms"
    expires_after="2021-08-01">
  <owner>danyao@chromium.org</owner>
  <owner>web-payments-team@google.com</owner>
  <owner>jinho.bang@samsung.com</owner>
  <summary>
    The time taken between dispatching an PaymentRequestEvent to a Service
    Worker and receiving a message that it finished handling the event. Includes
    the time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.PeriodicBackgroundSyncEvent.Time" units="ms"
    expires_after="2021-07-31">
  <owner>nator@chromium.org</owner>
  <owner>platform-capabilities@chromium.org</owner>
  <summary>
    The time taken between dispatching a PeriodicSyncEvent to a Service Worker
    and receiving a message that it finished handling the event. Includes the
    time for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.PushEvent.Time" units="ms" expires_after="M87">
  <owner>peter@chromium.org</owner>
  <summary>
    The time taken between dispatching a PushEvent to a Service Worker and
    receiving a message that it finished handling the event. Includes the time
    for the waitUntil() promise to settle.
  </summary>
</histogram>

<histogram name="ServiceWorker.PushSubscriptionChangeEvent.Time" units="ms"
    expires_after="M92">
  <owner>peter@chromium.org</owner>
  <owner>rayankans@chromium.org</owner>
  <owner>knollr@chromium.org</owner>
  <owner>viviy@google.com</owner>
  <summary>
    The time taken between dispatching a PushSubscriptionChangeEvent to a
    Service Worker and receiving a message that it finished handling the event.
    Includes the time for the waitUntil() promise to settle. The event is
    dispatched and finishes in PushMessagingRouter::FireSubscriptionChangeEvent.
  </summary>
</histogram>

<histogram name="ServiceWorker.RegisteredOriginCount" units="origins"
    expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The number of origins that have a service worker registration. Recorded near
    browser startup, when the service worker storage system is initialized.
  </summary>
</histogram>

<histogram name="ServiceWorker.Runtime" units="ms" expires_after="2020-07-30">
  <owner>falken@chromium.org</owner>
  <summary>
    The amount of time a service worker ran for (wall time). Starts recording
    when the service worker finished starting, and stops when the service worker
    finished stopping. Not recorded if DevTools was attached to the service
    worker at some point while it was running.
  </summary>
</histogram>

<histogram name="ServiceWorker.ScriptCachedMetadataSize" units="bytes"
    expires_after="2021-05-18">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The length of cached metadata of Service Worker scripts. Logged on each load
    of Service Worker script only when the cached metadata is available. It
    doesn't include the size of imported scripts. This histogram is only
    recorded for classic workers, not module workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.ScriptCachedMetadataTotalSize" units="bytes"
    expires_after="2021-05-18">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The total length of cached metadata of Service Worker scripts. Logged on
    each start of Service Worker only when the cached metadata is available. It
    includes the main script and imported scripts. This histogram is only
    recorded for classic workers, not module workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.ScriptCount" units="count"
    expires_after="2021-05-18">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The counts of scripts per Service Worker. Logged on each start of Service
    Worker. It includes the main script and imported scripts. This histogram is
    only recorded for classic workers, not module workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.ScriptSize" units="bytes"
    expires_after="2021-05-18">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The length of Service Worker scripts. Logged on each load of Service Worker
    script. It doesn't include the size of imported scripts. This histogram is
    only recorded for classic workers, not module workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.ScriptTotalSize" units="bytes"
    expires_after="2021-05-18">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The total length of Service Worker scripts. Logged on each start of Service
    Worker. It includes the main script and imported scripts. This histogram is
    only recorded for classic workers, not module workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.SendStopWorker.Status"
    enum="ServiceWorkerStatusCode" expires_after="M85">
  <owner>falken@chromium.org</owner>
  <summary>
    The result of trying to send the IPC message to a renderer process telling
    it to stop an embedded worker. Recorded in EmbeddedWorkerInstance::Stop.
    This was previously recorded for both the IPC and Mojo service worker
    implementations, but as of Jan 2017, this is only recorded for the IPC
    implementation. This histogram will be removed after the IPC implementation
    is removed.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartForNavigationHint.Result"
    enum="ServiceWorkerStartForNavigationHintResult" expires_after="2021-02-16">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of starting a service worker for a navigation hint.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartNewWorker.Time" units="ms"
    expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken to start a Service Worker that has not yet installed, from
    process allocation to ACK of started from the renderer (which occurs after
    script execution). This may include script download time. The metric is not
    recorded if DevTools was ever attached to the Service Worker during startup.
    See also ServiceWorker.StartWorker.Time for installed workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.BrowserThreadHopTime"
    units="microseconds" expires_after="M80">
  <owner>kinuko@chromium.org</owner>
  <summary>
    The sum of all the times spent posting tasks between the UI and IO threads
    during ServiceWorker startup. Recorded on a successful startup and when
    DevTools was not attached.

    Note: This metric drops reports on clients with low-resolution clocks, which
    means these reports will be biased against a portion of the population on
    Windows. See Windows.HasHighResolutionTimeTicks for the affected sample.

    Also note that this one's recorded slightly different from others as it's
    recorded even if the inter-process timings were inconsistent (see
    ServiceWorker.StartTiming.ClockConsistency).
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.ClockConsistency"
    enum="CrossProcessTimeDelta" expires_after="2020-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    Recorded on each successful service worker startup.
    ServiceWorker.StartTiming.* uses timing data from both the renderer process
    and browser process. This histogram describes whether the clocks are known
    to be accurate and consistent accross processes, and whether the actual
    timing data for this worker startup was consistent, i.e., TimeTicks did not
    go backwards.

    If the clocks and timing were inconsistent, ServiceWorker.StartTiming.*
    metrics (other than this one) are not recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.Duration" units="ms"
    expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken to start a service worker that is already installed, from
    start of the start sequence (finding a renderer) to ACK of started from the
    renderer (which occurs after script execution). The metric is not recorded
    if DevTools was ever attached to the Service Worker during startup. It does
    not include time, if any, waiting for the service worker to finish stopping
    before asking it to start, if that occurred.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.StartTiming.ReceivedStartWorkerToScriptEvaluationStart"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the renderer receiving the start worker IPC message,
    to (b) initial JavaScript evaluation starting on the worker thread. Recorded
    when ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.ScriptEvaluationEndToEnd" units="ms"
    expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) initial JavaScript evaluation finishing on the
    worker thread, to (b) the browser receiving the worker started IPC message
    (the final step of worker startup). Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.StartTiming.ScriptEvaluationStartToScriptEvaluationEnd"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) initial JavaScript evaluation starting on the worker
    thread, to (b) initial JavaScript evaluation finishing on the worker thread.
    Recorded when ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram
    name="ServiceWorker.StartTiming.SentStartWorkerToReceivedStartWorker"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the browser sending the start worker IPC message, to
    (b) the renderer receiving the start worker IPC message. Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.StartToReceivedStartWorker"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the start of service worker startup, to (b) the
    renderer receiving the start worker IPC message. Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.StartToScriptEvaluationEnd"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the start of service worker startup, to (b) initial
    JavaScript evaluation finishing on the worker thread. Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.StartToScriptEvaluationStart"
    units="ms" expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the start of service worker startup, to (b) initial
    JavaScript evaluation starting on the worker thread. Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartTiming.StartToSentStartWorker" units="ms"
    expires_after="2021-07-30">
  <owner>falken@chromium.org</owner>
  <owner>shimazu@chromium.org</owner>
  <summary>
    The time taken from (a) the start of service worker startup, to (b) the
    browser sending the start worker IPC message. Recorded when
    ServiceWorker.StartTiming.Duration is recorded.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.AfterFailureStreak"
    enum="ServiceWorkerStatusCode" expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of trying to start a service worker after it has failed
    consecutively. Recorded only for installed workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.FailureStreak" units="count"
    expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The number of consecutive startup failures of a service worker. Recorded
    each time the service worker failed (so there is double counting: failing
    twice results in 1 and 2 being logged). Only for installed workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.FailureStreakEnded" units="count"
    expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    When a worker startup succeeded after failing, the number of times the
    worker had consecutively failed. Recorded only for installed workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.Purpose"
    enum="ServiceWorkerMetrics.EventType" expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The purpose for starting up a service worker. Recorded only for installed
    workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.Status"
    enum="ServiceWorkerStatusCode" expires_after="2021-06-06">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of trying to start a Service Worker that is already installed.
    See also ServiceWorker.StartNewWorker.Status for new workers. See also
    ServiceWorker.StartWorker.StatusByPurpose_* for the breakdown by event type.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.StatusByPurpose"
    enum="ServiceWorkerStatusCode" expires_after="2021-06-20">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The result of trying to start a service worker for a particular event type
    (see ServiceWorker.StartWorker.Status for the total). Only recorded for
    installed workers. For event type:
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.Time" units="ms"
    expires_after="2021-06-06">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The time taken to start a Service Worker that is already installed, from
    process allocation to ACK of started from the renderer (which occurs after
    script execution). The metric is not recorded if DevTools was ever attached
    to the Service Worker during startup. See also
    ServiceWorker.StartNewWorker.Time for new workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.Timeout.StartPurpose"
    enum="ServiceWorkerMetrics.EventType" expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    Records the start purpose for a service worker that timed out while starting
    up. Recorded only for installed workers.
  </summary>
</histogram>

<histogram name="ServiceWorker.StartWorker.TimeoutPhase"
    enum="EmbeddedWorkerStartingPhase" expires_after="2021-01-31">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The phase the EmbeddedWorker was in when ServiceWorker startup timed out.
  </summary>
</histogram>

<histogram name="ServiceWorker.StopWorker.Time" units="ms"
    expires_after="2020-07-30">
  <owner>falken@chromium.org</owner>
  <summary>The time taken to stop a Service Worker.</summary>
</histogram>

<histogram name="ServiceWorker.Storage.DeleteAndStartOverResult"
    enum="ServiceWorkerDeleteAndStartOverResult" expires_after="M90">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    Records result of storage recovery operations in ServiceWorkerStorage.
  </summary>
</histogram>

<histogram name="ServiceWorker.Storage.PurgeResourceResult"
    enum="NetErrorCodes" expires_after="2020-06-30">
  <owner>nhiroki@chromium.org</owner>
  <summary>
    Records successes and failures of purging a stale resource in
    ServiceWorkerStorage.
  </summary>
</histogram>

<histogram name="ServiceWorker.Storage.RetryCountForRecovery" units="retries"
    expires_after="2021-06-30">
  <owner>bashi@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The counts of retries to recover after a Storage Service crash. Logged after
    a recovery, or the maximum number of retries is exceeded. See
    ServiceWorkerRegistry::OnRemoteStorageDisconnected() for the maximum number
    of retries.
  </summary>
</histogram>

<histogram name="ServiceWorker.WorkerForMessageFound" enum="Boolean"
    expires_after="M85">
  <owner>falken@chromium.org</owner>
  <summary>
    True if a message from the renderer intended for a browser-side embedded
    worker instance found its recipient. False if the instance did not exist
    when the message was received (e.g., it was a detached worker). Recorded in
    EmbeddedWorkerRegistry::GetWorkerForMessage.
  </summary>
</histogram>

<histogram name="ServiceWorker.WorkerStopped" enum="ServiceWorkerStoppedStatus"
    expires_after="2021-04-04">
  <owner>falken@chromium.org</owner>
  <owner>chrome-worker@google.com</owner>
  <summary>
    The mechanism by which a service worker entered running status STOPPED.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Cache" units="ms" expires_after="M95">
  <owner>wanderview@chromium.org</owner>
  <owner>dmurph@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time to perform operations on the Cache object in the ServiceWorker
    Cache API.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Cache.AllWritesResponseType"
    enum="FetchResponseType" expires_after="M77">
  <owner>jkarlin@chromium.org</owner>
  <summary>
    Records the response type to be added in the Cache by all operations that
    write to the cache.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Cache.Browser.Match.Initialized" units="ms"
    expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time to perform a 'match' operation on a given Cache when that cache is
    known to be fully initialized. This includes measurements for hits, misses,
    and errors.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Cache.Browser.Match.RelatedFetchEvent"
    units="ms" expires_after="2021-05-30">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time to perform a 'match' operation on a given Cache when the operation
    was initiated from a service worker currently processing a FetchEvent with a
    matching request URL. This includes measurements for hits, misses, and
    errors.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.CacheStorage" units="ms"
    expires_after="2021-05-23">
  <owner>dmurph@chromium.org</owner>
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time to perform operations on the CacheStorage object in the
    ServiceWorker Cache API.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.CreateCacheStorageResult"
    enum="BooleanCreated" expires_after="M77">
  <owner>jkarlin@chromium.org</owner>
  <summary>
    Whether a new ServiceWorkerCacheStorage and its directory were successfully
    created on disk.
  </summary>
</histogram>

<histogram
    name="ServiceWorkerCache.DidGenerateCacheableMetadataMessageInCacheStorage.OriginAllowed"
    enum="Boolean" expires_after="2020-12-31">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    Whether the origin provided in the
    DidGenerateCacheableMetadataInCacheStorage message is allowed for the given
    renderer process. This message is sent when the renderer has generated code
    cache for a script and wants to store it in cache_storage.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.ErrorStorageType"
    enum="CacheStorageErrorStorageType" expires_after="2021-06-20">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    Records where the generic kErrorStorage value is triggered within the
    cache_storage code.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.InitBackendResult"
    enum="CacheStorageErrorType" expires_after="M81">
  <owner>jkarlin@chromium.org</owner>
  <summary>
    The result of opening the backend in the ServiceWorker Cache API.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.ListOriginsIndexValidity"
    enum="CacheStorageIndexResult" expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The result from parsing and validating the index protobuf while calculating
    the list of cache_storage origins.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Scheduler.OperationDuration2" units="ms"
    expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time in ms from when an operation is started until it completes. This
    histogram differs from the old OperationDuration in that it uses a different
    bucket size to measure longer values.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Scheduler.QueueDuration2" units="ms"
    expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The time in ms from when an operation was queued until its task is posted.
    This histogram differs from the old QueueDuration in that it uses a
    different bucket size to measure longer values.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.Scheduler.QueueLength" units="operations"
    expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    The number of operations in the scheduling queue just before enqueuing a new
    operation.
  </summary>
</histogram>

<histogram name="ServiceWorkerCache.UsedIndexFileSize" enum="Boolean"
    expires_after="2021-06-08">
  <owner>wanderview@chromium.org</owner>
  <owner>chrome-owp-storage@google.com</owner>
  <summary>
    Whether the size was calculated using the values stored in the origin's
    index file. If this is false, then the size was recalculated by loading all
    of the individual cache backends.
  </summary>
</histogram>

</histograms>

</histogram-configuration>