Ooops, bad example that is. That one was finally not for a dynamically named histogram do it didn't require a function. As there is already a macro for those they'd only need a respective function.

Sparse histograms are supported via the UMA_HISTOGRAM_SPARSE_SLOWLY macro.  Unlike all of the other UMA_HISTOGRAM_* macros, it supports runtime variable/dynamic names.  Yes, it's a bit confusing – sorry about that.  We should perhaps globally replace the UMA_HISTOGRAM_SPARSE_SLOWLY macro with an UmaHistogramSparseSlowly function, to make that clearer/less confusing.

For reporting values > 1 to linear and enum histograms, we generally discourage doing so, as it's easy for outliers to drown out the primary signal.  This can be worked around using custom analysis, but our dashboards don't easily support it, and it's not necessarily obvious to someone implementing a new metric that they should be watching out for this.  So, it's currently working as intended (TM) that it's a bit clunkier to emit such data.

Actually, we could probably name the function UmaHistogramSparse, since the slowly isn't really all that necessary when it's not being compared to the other UMA_HISTOGRAM_* macros.

Thanks for the update.

As for the way sparse histograms macros work, it is indeed borderline impossible to know they accept variable names. The documentation on histogram_macros.h specifically states that names should be constants and there's no exception mentioned anywhere. So either the function approach you suggested or an update to that documentation seem to be in order. WDYT?

For the values > 1 I understand you are trying to avoid incorrect usage of that feature -- should it exist -- by making it harder to implement it. I can't say I completely agree with the approach but I can certainly understand the rationale. So I can accept this as WAI.

I'm retargeting this bug to be about changing the sparse histogram macro to be a function, for consistency with the other metric functions.  This is mostly a global search/replace operation, so might be a good first bug for anyone wanting to gain familiarity with the Chromium toolchain – including "git cl format" and the code review process.

Regarding values > 1, it might help if you post your use cases (possibly in a separate bug).  I think I'm aware of just three sets of histograms that currently have a reasonable use for this behavior: (1) measuring network bytes used by various Chrome components, (2) measuring queue times for various tasks, and (3) recording data that's cached in local prefs while Chrome is offline.  For (3), I think the best long-term fix is to make UMA more resilient to offline use-cases... and I think it's also reasonable to use sparse histograms in the meantime.  For (1) and (2), I'm honestly not super happy with the current implementation, as the data is really susceptible to being completely thrown off by outliers.  I think both of these would be better served by a set of histograms, one per current bucket... or some other, as-yet-undefined recording mechanism.  But, it's possible that there are use cases that I'm overlooking, that are better motivations for this functionality.

Continuing here just to see if it's worth creation a new issue for the "value > 1" case)

One example is LogStateCountMetrics in metrics_finalization_task.cc [1]. This method was written to work with a single entry per call and so uses the regular macro calls. But the *.ActionAttempts.* linear metrics could be reported with a single call by querying SQL with count-and-group-by. But I expect the linear histogram case to be less common.

And it's not enough to only search for the Get*Factory cases as in others the code was adapted to use the macros. This is the case in ReportMetricsFor in the same file [2] that reports a count value to a bucket of an enum histogram. My (not very trustworthy) memory tells me is the more common I've seen.


[1] https://cs.chromium.org/chromium/src/components/offline_pages/core/prefetch/metrics_finalization_task.cc?l=97

[2] https://cs.chromium.org/chromium/src/components/offline_pages/core/prefetch/metrics_finalization_task.cc?l=163

Sorry for the long radio silence here!  From my (somewhat superficial) grok of the code, it looks like LogStateCountMetrics is piping some data that was persisted to disk back into UMA.  Am I correct in understanding that the DB column is incremented by 1 at a time?  If so, IMO the best solution would allow simply using UMA_HISTOGRAM macros to record that data, rather than persisting it via the DB.

For the *.ActionAttempts.* metrics, it's a similar case; but also, we're already doing some amount of work on a per-URL basis.  Would it actually make a meaningful performance difference to use count-and-group-by just for those metrics?  (I assume you're asking about changing this for performance reasons – is that accurate?)

Anyhow, I'm going to go ahead an make the naming change that I've morphed this bug into tracking.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/16d5d5f44dfda79e8500a57acf475c032a13635e

commit 16d5d5f44dfda79e8500a57acf475c032a13635e
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 08 00:32:44 2017

[Cleanup] Replace UMA_HISTOGRAM_SPARSE_SLOWLY with UmaHistogramSparse.

The sparse histogram macro is the only one that allows for runtime-variable
names, which sometimes leads to confusion. Use a function syntax for it, for
consistency with other UMA-recording functions that support runtime-variable
names.

While updating the API, let's go ahead and drop "slowly" from the name. It was
(arguably) useful to distinguish this from the other macros, which are designed
to be blazing fast. However, it's not particularly slow -- only truly
performance-sensitive code should avoid it. Hence, there's no need to use a
longer and scarier name.

This CL only covers //base.  Will migrate the other uses in follow-up CLs.

R=asvitkine@chromium.org
TBR=estark@chromium.org,thestig@chromium.org

Bug:  773850 
Change-Id: Ibf5c854c47fddc9b584aa401a0f48999031a29f4
Reviewed-on: https://chromium-review.googlesource.com/812450
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522642}
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/android/java/src/org/chromium/base/metrics/RecordHistogram.java
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/android/library_loader/library_loader_hooks.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/files/file_posix.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/files/file_win.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/memory/shared_memory_win.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/histogram.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/histogram_functions.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/histogram_functions.h
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/histogram_functions_unittest.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/histogram_samples.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/persistent_memory_allocator.cc
[modify] https://crrev.com/16d5d5f44dfda79e8500a57acf475c032a13635e/base/metrics/sparse_histogram_unittest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014

commit 0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 08 20:58:18 2017

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

This CL only covers //net.  Will migrate the other uses in sibling CLs.

R=asvitkine@chromium.org
TBR=rsleevi@chromium.org

Bug:  773850 
Change-Id: Ie0cca241d415335177cb02aa1c1271cf864562c0
Reviewed-on: https://chromium-review.googlesource.com/815902
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ryan Sleevi <rsleevi@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522871}
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/base/network_change_notifier.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/cert/cert_verify_proc.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/cert/cert_verify_proc_android.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/dns/host_resolver_impl.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/http/http_cache_transaction.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/http/http_stream_factory_impl_job_controller.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/http/transport_security_state.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/nqe/network_quality_estimator.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/quic/chromium/crypto/proof_verifier_chromium.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/quic/chromium/quic_chromium_client_session.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/quic/chromium/quic_connection_logger.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/quic/chromium/quic_stream_factory.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/quic/core/quic_crypto_client_handshaker.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/socket/ssl_client_socket_impl.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/socket/ssl_client_socket_pool.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/socket/udp_socket_posix.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/socket/udp_socket_win.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/spdy/chromium/spdy_session.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/tools/quic/quic_simple_server_packet_writer.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/url_request/url_request_context.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/url_request/url_request_http_job.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/websockets/websocket_basic_handshake_stream.cc
[modify] https://crrev.com/0eb398011d5c29c64e8b2a15e3c0ca7bdb65e014/net/websockets/websocket_stream.cc

Re #7 (sorry for the delay):


IRT LogStateCountMetrics:

Our main DB table has a "state" column that reflects in what stage in the Prefetching pipeline each row is currently at. What LogStateCountMetrics does is reporting a snapshot of the current row count for each state. This allows us to detect changes in the distribution of states and it already helped us to fix a bug when a state supposed to be very brief started showing an unexpected population growth. Reporting these values one-by-one upon each state transition wouldn't be helpful for this.


IRT *.ActionAttempts.* metrics: 

This series of histograms reports the number of attempts to execute a few actions for each row when it reached the end of the pipeline. So if we tried to download the article for that row twice, it would report 1 sample in bucket "2" of OfflinePages.Prefetching.ActionAttempts.DownloadInitiation.

We finally chose reporting them row-by-row as there were other metrics -- all reported in ReportMetricsFor -- that had to be done that way anyway. But a more optimal approach to report this series of metrics would be to count rows grouping by attempt values so that we could report "all rows for which 2 download attempts were made" in one fell swoop. Hence the suggestion to allow specifying the sample count for the bucket being reported to.

@Carlos: Got it, thanks for the further details!  My overall takeaway is that there would be some value to adding the increment-by-n functionality, though it doesn't sound too mission-critical.  And, I would definitely want to add documentation stating that it's rarely recommended to use the API, as it's easy to introduce significant noise – but that's not any different than if a client currently uses a for-loop to simulate the API.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1edb6f189054b147aa83842171f9b37a885d6f34

commit 1edb6f189054b147aa83842171f9b37a885d6f34
Author: Ilya Sherman <isherman@chromium.org>
Date: Tue Dec 12 04:00:42 2017

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

This CL only covers //components.  Will migrate the other uses in sibling CLs.

R=blundell@chromium.org

Bug:  773850 
Change-Id: Ia57dc5c75b5d2ab57436be3264b20c9d2b9b4342
Reviewed-on: https://chromium-review.googlesource.com/818726
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523321}
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/autofill/core/browser/autofill_metrics.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_protocol.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_stats.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/data_reduction_proxy/core/browser/warmup_url_fetcher.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/domain_reliability/uploader.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/download/content/internal/download_driver_impl.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/download/internal/stats.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/drive/resource_metadata_storage.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/favicon/core/favicon_handler.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/favicon/core/large_icon_service.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/guest_view/browser/bad_message.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/history/core/browser/history_database.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/infobars/core/infobar_container.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/language_usage_metrics/language_usage_metrics.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/metrics/metrics_reporting_service.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/metrics/metrics_service.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/metrics/metrics_state_manager.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/metrics/stability_metrics_helper.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/nacl/browser/bad_message.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/network_time/network_time_tracker.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/ntp_snippets/remote/json_request.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/ntp_snippets/remote/remote_suggestions_fetcher_impl.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/ntp_snippets/remote/remote_suggestions_provider_impl.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/ntp_tiles/metrics.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/offline_pages/core/prefetch/metrics_finalization_task.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/offline_pages/core/prefetch/stale_entry_finalizer_task.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/omnibox/browser/clipboard_url_provider.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/omnibox/browser/search_suggestion_parser.cc
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[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/password_manager/core/browser/android_affiliation/affiliation_fetcher.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/password_manager/core/browser/login_database.cc
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[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/safe_browsing/db/prefix_set.cc
[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/safe_browsing/db/v4_protocol_manager_util.cc
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[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/safe_browsing/password_protection/password_protection_request.cc
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[modify] https://crrev.com/1edb6f189054b147aa83842171f9b37a885d6f34/components/variations/service/variations_service.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/982457e6b3c60f57237def506bbb4dd445471f11

commit 982457e6b3c60f57237def506bbb4dd445471f11
Author: Ilya Sherman <isherman@chromium.org>
Date: Wed Dec 13 02:19:36 2017

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

This CL only covers //chrome.  Will migrate the other uses in sibling CLs.

R=sky@chromium.org

Bug:  773850 
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I38a114dab508fb0a0d1212bd64457be0c4619727
Reviewed-on: https://chromium-review.googlesource.com/822033
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523656}
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/chromeos/input_method/input_method_manager_impl.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/chromeos/login/enrollment/enrollment_uma.cc
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/install_verification/win/install_verification.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/mac/keychain_reauthorize.mm
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/mod_pagespeed/mod_pagespeed_metrics.cc
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/certificate_reporting_service.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/chrome_cleaner/chrome_cleaner_fetcher_win.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/chrome_cleaner/chrome_cleaner_runner_win.cc
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/download_protection/ppapi_download_request.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/incident_reporting/module_integrity_verifier_win.cc
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/safe_browsing/safe_browsing_store_file.cc
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[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ssl/chrome_expect_ct_reporter.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/supervised_user/supervised_user_navigation_throttle.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/android/infobars/infobar_container_android.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/chrome_bubble_manager.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/startup/startup_browser_creator_impl.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/webui/log_web_ui_url.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/webui/media_router/media_router_webui_message_handler.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/vr/metrics_helper.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/web_applications/web_app_mac.mm
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/browser/win/chrome_elf_init.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/common/safe_browsing/file_type_policies.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/installer/util/shell_util.cc
[modify] https://crrev.com/982457e6b3c60f57237def506bbb4dd445471f11/chrome/renderer/net/net_error_helper_core.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1c811db2dcd39a8e353ce4aae7336ff82548a9a4

commit 1c811db2dcd39a8e353ce4aae7336ff82548a9a4
Author: Ilya Sherman <isherman@chromium.org>
Date: Thu Dec 14 10:36:18 2017

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

This CL covers all of the remaining uses other than //third_party (and the
macro itself).

R=sky@chromium.org
TBR=wfh@chromium.org

Bug:  773850 
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: Icf1931aee5a5ccba6205a1c711423c596ca39d45
Reviewed-on: https://chromium-review.googlesource.com/823602
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524037}
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/bad_message.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/bluetooth/bluetooth_metrics.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/browser_child_process_host_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/download/download_request_core.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/download/download_stats.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/gpu/gpu_data_manager_impl_private.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/gpu/gpu_process_host.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/loader/resource_dispatcher_host_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/renderer_host/dwrite_font_proxy_message_filter_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/renderer_host/media/video_capture_controller.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/renderer_host/pepper/browser_ppapi_host_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/service_worker/service_worker_metrics.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/browser/zygote_host/zygote_communication_linux.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/common/quarantine/quarantine_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/ppapi_plugin/ppapi_thread.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/renderer/media/audio_renderer_mixer_manager.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/renderer/media/rtc_peer_connection_handler.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/renderer/pepper/content_decryptor_delegate.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/content/renderer/pepper/pepper_plugin_instance_metrics.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/device/bluetooth/bluetooth_device_android.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/device/geolocation/network_location_request.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/device/serial/serial_device_enumerator_mac.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/device/serial/serial_device_enumerator_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/device/vr/openvr/openvr_device.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/extensions/browser/api/metrics_private/metrics_private_api.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/extensions/browser/bad_message.cc
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[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/extensions/browser/extension_protocols.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/extensions/browser/updater/extension_downloader.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/google_apis/drive/drive_api_requests.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/google_apis/drive/files_list_request_runner.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/google_apis/gaia/oauth2_access_token_fetcher_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/google_apis/gcm/engine/connection_factory_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/gpu/config/gpu_info_collector.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/gpu/ipc/service/direct_composition_surface_win.cc
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[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/ios/chrome/browser/ui/download/legacy_download_manager_controller.mm
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[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/media/audio/mac/audio_low_latency_input_mac.cc
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[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/media/audio/win/core_audio_util_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/media/base/win/mf_helpers.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/media/blink/webcontentdecryptionmodulesession_impl.cc
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[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/services/service_manager/sandbox/win/sandbox_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/sql/connection.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/sql/recovery.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/ui/display/win/screen_win.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/ui/gl/angle_platform_impl.cc
[modify] https://crrev.com/1c811db2dcd39a8e353ce4aae7336ff82548a9a4/ui/keyboard/keyboard_controller.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/mini_chromium/+/d1943e187f4787e769f92b367313c7aec4bc596d

commit d1943e187f4787e769f92b367313c7aec4bc596d
Author: Ilya Sherman <isherman@chromium.org>
Date: Thu Dec 14 20:25:46 2017

Add a stub for Chromium's base::UmaHistogramSparse().

Bug:  chromium:773850 
Change-Id: I6d2416e5dbb36215355eaaf0c7dc7bdbc627df99
Reviewed-on: https://chromium-review.googlesource.com/827552
Reviewed-by: Mark Mentovai <mark@chromium.org>

[add] https://crrev.com/d1943e187f4787e769f92b367313c7aec4bc596d/base/metrics/histogram_functions.h
[modify] https://crrev.com/d1943e187f4787e769f92b367313c7aec4bc596d/base/base.gyp
[modify] https://crrev.com/d1943e187f4787e769f92b367313c7aec4bc596d/base/BUILD.gn

The following revision refers to this bug:
  https://chromium.googlesource.com/crashpad/crashpad.git/+/7662fb087f6c9d172a31e277a2dff465311f2d74

commit 7662fb087f6c9d172a31e277a2dff465311f2d74
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 15 04:19:44 2017

Roll mini_chromium a12ed4a6..20182dd2

$ git log --oneline a12ed4a6..20182dd2
20182dd Add missing newline at EOF after d1943e187f47
d1943e1 Add a stub for Chromium's base::UmaHistogramSparse().
9920849 gn, mac: Various GN build fixes
0b16698 gn, mac: Tell libtool not to warn about empty .o files

R=mark@chromium.org

Bug:  chromium:773850 
Change-Id: I2fb4b7ed8a8efa8b3d37f1b8f131396e9a2bbfdc
Reviewed-on: https://chromium-review.googlesource.com/827648
Reviewed-by: Mark Mentovai <mark@chromium.org>

[modify] https://crrev.com/7662fb087f6c9d172a31e277a2dff465311f2d74/DEPS

The following revision refers to this bug:
  https://chromium.googlesource.com/crashpad/crashpad.git/+/344acadfdd3670a499f118005a5f3a8a056f431a

commit 344acadfdd3670a499f118005a5f3a8a056f431a
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 15 19:17:46 2017

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

R=mark@chromium.org

Bug:  chromium:773850 
Change-Id: Idef7b4c821dcac03e095d1400534ddf503a22423
Reviewed-on: https://chromium-review.googlesource.com/828530
Reviewed-by: Mark Mentovai <mark@chromium.org>

[modify] https://crrev.com/344acadfdd3670a499f118005a5f3a8a056f431a/util/misc/metrics.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/mini_chromium/+/7701901ec90eb1be1f3966cdceb7536bab3834a9

commit 7701901ec90eb1be1f3966cdceb7536bab3834a9
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 15 20:58:24 2017

Remove the deprecated sparse_histogram.h header.

The functionality provided by this header has been replaced by
equivalent functionality in histogram_functions.h.

R=mark@chromium.org

Bug:  chromium:773850 
Change-Id: I543d5c4d4ab874aaddcf3d9dddf6e486c310cdb0
Reviewed-on: https://chromium-review.googlesource.com/830135
Reviewed-by: Mark Mentovai <mark@chromium.org>

[delete] https://crrev.com/e2f01606854d4f3d83818f78019f6b7d7deffbf0/base/metrics/sparse_histogram.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a361f9f615e641501c37f747ce32afd2069a97af

commit a361f9f615e641501c37f747ce32afd2069a97af
Author: Ilya Sherman <isherman@chromium.org>
Date: Fri Dec 15 22:22:53 2017

Update Crashpad to 10ff56eee5da29d14b86818b88a93d3e96b4bacd

05dee13e844d fuchsia: Add QEMU and helper script to start/stop instance
169731495268 fuchsia: Make Filesystem.RemoveFile, .RemoveDirectory pass
7662fb087f6c Roll mini_chromium a12ed4a6..20182dd2
344acadfdd36 [Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to
             base::UmaHistogramSparse()
10ff56eee5da Include the appropriate header for BUILD_FUSCHIA

R=mark@chromium.org

Bug:  773850 
Change-Id: I649547ba3809ab836ea5d9da9fd77c9daaeff669
Reviewed-on: https://chromium-review.googlesource.com/830811
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524486}
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/README.chromium
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/.gitignore
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/DEPS
[add] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/build/run_fuchsia_qemu.py
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/util/file/file_io_posix.cc
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/util/file/filesystem_test.cc
[modify] https://crrev.com/a361f9f615e641501c37f747ce32afd2069a97af/third_party/crashpad/crashpad/util/misc/metrics.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0762f515d8fcb8fbbef34448aa4d5dd6614286d3

commit 0762f515d8fcb8fbbef34448aa4d5dd6614286d3
Author: Ilya Sherman <isherman@chromium.org>
Date: Mon Jan 08 18:38:32 2018

[Simple Cache] Don't split the file descriptor histograms by cache type.

The data recorded to these histograms does not depend on the cache type, so
there's no need to split them along this axis.

This is also helpful toward removing the UMA_HISTOGRAM_SPARSE_SLOWLY macro, in
favor of the base::UmaHistogramSparse() function. See
https://chromium-review.googlesource.com/c/chromium/src/+/830660 for more
context.

R=morlovich@chromium.org, pasko@chromium.org

Bug:  773850 
Change-Id: Icf3da29552903e4afd2af21bd8817550f1ab2851
Reviewed-on: https://chromium-review.googlesource.com/853128
Reviewed-by: Maks Orlovich <morlovich@chromium.org>
Reviewed-by: Egor Pasko <pasko@chromium.org>
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527682}
[modify] https://crrev.com/0762f515d8fcb8fbbef34448aa4d5dd6614286d3/net/disk_cache/simple/simple_backend_impl.cc
[modify] https://crrev.com/0762f515d8fcb8fbbef34448aa4d5dd6614286d3/net/disk_cache/simple/simple_histogram_macros.h
[modify] https://crrev.com/0762f515d8fcb8fbbef34448aa4d5dd6614286d3/tools/metrics/histograms/histograms.xml

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5ed1d19244d15c71c3079c9105b2c291dc91f1da

commit 5ed1d19244d15c71c3079c9105b2c291dc91f1da
Author: Ilya Sherman <isherman@chromium.org>
Date: Mon Jan 08 22:47:33 2018

[Cleanup] Rename UMA_HISTOGRAM_SPARSE_SLOWLY to base::UmaHistogramSparse().

This CL covers the final remaining uses, and removes the
UMA_HISTOGRAM_SPARSE_SLOWLY macro.

R=sky@chromium.org

Bug:  773850 
Change-Id: I63ab5c9f2f17d554738099603d4c91332fc76aed
Reviewed-on: https://chromium-review.googlesource.com/830660
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Egor Pasko <pasko@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527791}
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/base/metrics/histogram_macros.h
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/base/metrics/histogram_macros_internal.h
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/chromecast/browser/metrics/cast_stability_metrics_provider.cc
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/chromeos/geolocation/simple_geolocation_request.cc
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/chromeos/timezone/timezone_request.cc
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/extensions/browser/extension_protocols.cc
[modify] https://crrev.com/5ed1d19244d15c71c3079c9105b2c291dc91f1da/tools/metrics/histograms/find_unmapped_histograms.py