chrome/browser/metrics/drive_metrics_provider.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_METRICS_DRIVE_METRICS_PROVIDER_H_
   6 #define CHROME_BROWSER_METRICS_DRIVE_METRICS_PROVIDER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/macros.h"
  10 #include "base/memory/weak_ptr.h"
  11 #include "base/threading/thread_checker.h"
  12 #include "components/metrics/metrics_provider.h"
  13 #include "components/metrics/proto/system_profile.pb.h"
  14
  15 // Provides metrics about the local drives on a user's computer. Currently only
  16 // checks to see if they incur a seek-time penalty (e.g. if they're SSDs).
  17 //
  18 // Defers gathering metrics until after "rush hour" (startup) so as to not bog
  19 // down the FILE thread.
  20 class DriveMetricsProvider : public metrics::MetricsProvider {
  21  public:
  22   DriveMetricsProvider();
  23   ~DriveMetricsProvider() override;
  24
  25   // metrics::MetricsDataProvider:
  26   void ProvideSystemProfileMetrics(
  27       metrics::SystemProfileProto* system_profile_proto) override;
  28
  29   // Called by ChromeMetricsServiceClient to start gathering metrics.
  30   void GetDriveMetrics(const base::Closure& done);
  31
  32  private:
  33   // A response to querying a drive as to whether it incurs a seek penalty.
  34   // |has_seek_penalty| is set if |success| is true.
  35   struct SeekPenaltyResponse {
  36     SeekPenaltyResponse();
  37     bool success;
  38     bool has_seek_penalty;
  39   };
  40
  41   struct DriveMetrics {
  42     SeekPenaltyResponse app_drive;
  43     SeekPenaltyResponse user_data_drive;
  44   };
  45
  46   // Gather metrics about various drives on the FILE thread.
  47   static DriveMetrics GetDriveMetricsOnFileThread();
  48
  49   // Tries to determine whether there is a penalty for seeking on the drive that
  50   // hosts |path_service_key| (for example: the drive that holds "Local State").
  51   static void QuerySeekPenalty(int path_service_key,
  52                                SeekPenaltyResponse* response);
  53
  54   // Called when metrics are done being gathered from the FILE thread.
  55   void GotDriveMetrics(const DriveMetrics& metrics);
  56
  57   // Fills |drive| with information from successful |response|s.
  58   void FillDriveMetrics(
  59       const SeekPenaltyResponse& response,
  60       metrics::SystemProfileProto::Hardware::Drive* drive);
  61
  62   // Information gathered about various important drives.
  63   DriveMetrics metrics_;
  64
  65   // Called when metrics are done being collected.
  66   base::Closure got_metrics_callback_;
  67
  68   base::ThreadChecker thread_checker_;
  69   base::WeakPtrFactory<DriveMetricsProvider> weak_ptr_factory_;
  70
  71   DISALLOW_COPY_AND_ASSIGN(DriveMetricsProvider);
  72 };
  73
  74 #endif  // CHROME_BROWSER_METRICS_DRIVE_METRICS_PROVIDER_H_