DNS histogram cleanup, part 3

This CL removes all the old DNS.Resolve* and AsyncDNS.Resolve*
histograms and replaces them with a new set. The new Net.DNS.Resolve*
histograms measure timing and success/failure at the Job layer, and each
type of Task gets its own set to measure Task layer timing and
success/failure.

Bug: 769320
Change-Id: I0b0df897310a474fd11022f932724c8d40789090
Reviewed-on: https://chromium-review.googlesource.com/687836
Commit-Queue: Miriam Gershenson <mgersh@chromium.org>
Reviewed-by: Julia Tuttle <juliatuttle@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#505215}

net/dns/host_resolver_impl.cc

@@ -693,7 +693,6 @@ class HostResolverImpl::ProcTask
         attempt_number_(0),
         completed_attempt_number_(0),
         completed_attempt_error_(ERR_UNEXPECTED),
-        had_non_speculative_request_(false),
         net_log_(job_net_log) {
     if (!params_.resolver_proc.get())
       params_.resolver_proc = HostResolverProc::GetDefault();
@@ -721,11 +720,6 @@ class HostResolverImpl::ProcTask
     net_log_.EndEvent(NetLogEventType::HOST_RESOLVER_IMPL_PROC_TASK);
   }
 
-  void set_had_non_speculative_request() {
-    DCHECK(network_task_runner_->BelongsToCurrentThread());
-    had_non_speculative_request_ = true;
-  }
-
   bool was_canceled() const {
     DCHECK(network_task_runner_->BelongsToCurrentThread());
     return callback_.is_null();
@@ -816,11 +810,6 @@ class HostResolverImpl::ProcTask
     if (error != OK && NetworkChangeNotifier::IsOffline())
       error = ERR_INTERNET_DISCONNECTED;
 
-    // If this is the first attempt that is finishing later, then record data
-    // for the first attempt. Won't contaminate with retry attempt's data.
-    if (!was_retry_attempt)
-      RecordPerformanceHistograms(start_time, error, os_error);
-
     RecordAttemptHistograms(start_time, attempt_number, error, os_error);
 
     if (was_canceled())
@@ -841,6 +830,8 @@ class HostResolverImpl::ProcTask
     if (was_completed())
       return;
 
+    RecordTaskHistograms(start_time, error, os_error);
+
     // Copy the results from the first worker thread that resolves the host.
     results_ = results;
     completed_attempt_number_ = attempt_number;
@@ -864,76 +855,20 @@ class HostResolverImpl::ProcTask
     callback_.Run(error, results_);
   }
 
-  void RecordPerformanceHistograms(const base::TimeTicks& start_time,
+  void RecordTaskHistograms(const base::TimeTicks& start_time,
                             const int error,
                             const int os_error) const {
     DCHECK(network_task_runner_->BelongsToCurrentThread());
-    enum Category {  // Used in UMA_HISTOGRAM_ENUMERATION.
-      RESOLVE_SUCCESS,
-      RESOLVE_FAIL,
-      RESOLVE_SPECULATIVE_SUCCESS,
-      RESOLVE_SPECULATIVE_FAIL,
-      RESOLVE_MAX,  // Bounding value.
-    };
-    Category category = RESOLVE_MAX;  // Illegal value for later DCHECK only.
-
     base::TimeDelta duration = base::TimeTicks::Now() - start_time;
-    if (error == OK) {
-      if (had_non_speculative_request_) {
-        category = RESOLVE_SUCCESS;
-        UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSuccess", duration);
-      } else {
-        category = RESOLVE_SPECULATIVE_SUCCESS;
-        UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSpeculativeSuccess", duration);
-      }
+    if (error == OK)
+      UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ProcTask.SuccessTime", duration);
+    else
+      UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ProcTask.FailureTime", duration);
 
-      // Log DNS lookups based on |address_family|. This will help us determine
-      // if IPv4 or IPv4/6 lookups are faster or slower.
-      switch (key_.address_family) {
-        case ADDRESS_FAMILY_IPV4:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSuccess_FAMILY_IPV4",
-                                       duration);
-          break;
-        case ADDRESS_FAMILY_IPV6:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSuccess_FAMILY_IPV6",
-                                       duration);
-          break;
-        case ADDRESS_FAMILY_UNSPECIFIED:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSuccess_FAMILY_UNSPEC",
-                                       duration);
-          break;
-      }
-    } else {
-      if (had_non_speculative_request_) {
-        category = RESOLVE_FAIL;
-        UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveFail", duration);
-      } else {
-        category = RESOLVE_SPECULATIVE_FAIL;
-        UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveSpeculativeFail", duration);
-      }
-      // Log DNS lookups based on |address_family|. This will help us determine
-      // if IPv4 or IPv4/6 lookups are faster or slower.
-      switch (key_.address_family) {
-        case ADDRESS_FAMILY_IPV4:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveFail_FAMILY_IPV4", duration);
-          break;
-        case ADDRESS_FAMILY_IPV6:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveFail_FAMILY_IPV6", duration);
-          break;
-        case ADDRESS_FAMILY_UNSPECIFIED:
-          UMA_HISTOGRAM_LONG_TIMES_100("DNS.ResolveFail_FAMILY_UNSPEC",
-                                       duration);
-          break;
-      }
     UMA_HISTOGRAM_CUSTOM_ENUMERATION(kOSErrorsForGetAddrinfoHistogramName,
                                      std::abs(os_error),
                                      GetAllGetAddrinfoOSErrors());
   }
-    DCHECK_LT(static_cast<int>(category),
-              static_cast<int>(RESOLVE_MAX));  // Be sure it was set.
-
-    UMA_HISTOGRAM_ENUMERATION("DNS.ResolveCategory", category, RESOLVE_MAX);
-  }
 
   void RecordAttemptHistograms(const base::TimeTicks& start_time,
                                const uint32_t attempt_number,
@@ -1017,12 +952,6 @@ class HostResolverImpl::ProcTask
   // The time when retry attempt was finished.
   base::TimeTicks retry_attempt_finished_time_;
 
-  // True if a non-speculative request was ever attached to this job
-  // (regardless of whether or not it was later canceled.
-  // This boolean is used for histogramming the duration of jobs used to
-  // service non-speculative requests.
-  bool had_non_speculative_request_;
-
   AddressList results_;
 
   NetLogWithSource net_log_;
@@ -1351,12 +1280,8 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
         base::Bind(&NetLogJobAttachCallback, request->source_net_log().source(),
                    priority()));
 
-    // TODO(szym): Check if this is still needed.
-    if (!request->info().is_speculative()) {
+    if (!request->info().is_speculative())
       had_non_speculative_request_ = true;
-      if (proc_task_.get())
-        proc_task_->set_had_non_speculative_request();
-    }
 
     requests_.push_back(request);
 
@@ -1533,9 +1458,10 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
 
     had_dns_config_ = resolver_->HaveDnsConfig();
 
-    base::TimeTicks now = base::TimeTicks::Now();
-    base::TimeDelta queue_time = now - creation_time_;
-    base::TimeDelta queue_time_after_change = now - priority_change_time_;
+    start_time_ = base::TimeTicks::Now();
+    base::TimeDelta queue_time = start_time_ - creation_time_;
+    base::TimeDelta queue_time_after_change =
+        start_time_ - priority_change_time_;
 
     DNS_HISTOGRAM_BY_PRIORITY("Net.DNS.JobQueueTime", priority(), queue_time);
     DNS_HISTOGRAM_BY_PRIORITY("Net.DNS.JobQueueTimeAfterChange", priority(),
@@ -1565,8 +1491,6 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
                                 base::Unretained(this), base::TimeTicks::Now()),
                      net_log_);
 
-    if (had_non_speculative_request_)
-      proc_task_->set_had_non_speculative_request();
     // Start() could be called from within Resolve(), hence it must NOT directly
     // call OnProcTaskComplete, for example, on synchronous failure.
     proc_task_->Start();
@@ -1588,7 +1512,7 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
         } else {
           UmaAsyncDnsResolveStatus(RESOLVE_STATUS_PROC_SUCCESS);
         }
-        UMA_HISTOGRAM_SPARSE_SLOWLY("AsyncDNS.ResolveError",
+        UMA_HISTOGRAM_SPARSE_SLOWLY("Net.DNS.DnsTask.Errors",
                                     std::abs(dns_task_error_));
         resolver_->OnDnsTaskResolve(dns_task_error_);
       } else {
@@ -1631,7 +1555,7 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
   void OnDnsTaskFailure(const base::WeakPtr<DnsTask>& dns_task,
                         base::TimeDelta duration,
                         int net_error) {
-    UMA_HISTOGRAM_LONG_TIMES_100("AsyncDNS.ResolveFail", duration);
+    UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.DnsTask.FailureTime", duration);
 
     if (!dns_task)
       return;
@@ -1666,22 +1590,8 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
       OnDnsTaskFailure(dns_task_->AsWeakPtr(), duration, net_error);
       return;
     }
-    UMA_HISTOGRAM_LONG_TIMES_100("AsyncDNS.ResolveSuccess", duration);
-    // Log DNS lookups based on |address_family|.
-    switch (key_.address_family) {
-      case ADDRESS_FAMILY_IPV4:
-        UMA_HISTOGRAM_LONG_TIMES_100("AsyncDNS.ResolveSuccess_FAMILY_IPV4",
-                                     duration);
-        break;
-      case ADDRESS_FAMILY_IPV6:
-        UMA_HISTOGRAM_LONG_TIMES_100("AsyncDNS.ResolveSuccess_FAMILY_IPV6",
-                                     duration);
-        break;
-      case ADDRESS_FAMILY_UNSPECIFIED:
-        UMA_HISTOGRAM_LONG_TIMES_100("AsyncDNS.ResolveSuccess_FAMILY_UNSPEC",
-                                     duration);
-        break;
-    }
+
+    UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.DnsTask.SuccessTime", duration);
 
     UmaAsyncDnsResolveStatus(RESOLVE_STATUS_DNS_SUCCESS);
     RecordTTL(ttl);
@@ -1712,6 +1622,69 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
       dns_task_->StartSecondTransaction();
   }
 
+  void RecordJobHistograms(int error) {
+    enum Category {  // Used in UMA_HISTOGRAM_ENUMERATION.
+      RESOLVE_SUCCESS,
+      RESOLVE_FAIL,
+      RESOLVE_SPECULATIVE_SUCCESS,
+      RESOLVE_SPECULATIVE_FAIL,
+      RESOLVE_MAX,  // Bounding value.
+    };
+    Category category = RESOLVE_MAX;  // Illegal value for later DCHECK only.
+
+    base::TimeDelta duration = base::TimeTicks::Now() - start_time_;
+    if (error == OK) {
+      if (had_non_speculative_request_) {
+        category = RESOLVE_SUCCESS;
+        UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime", duration);
+        switch (key_.address_family) {
+          case ADDRESS_FAMILY_IPV4:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.IPV4",
+                                         duration);
+            break;
+          case ADDRESS_FAMILY_IPV6:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.IPV6",
+                                         duration);
+            break;
+          case ADDRESS_FAMILY_UNSPECIFIED:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.UNSPEC",
+                                         duration);
+            break;
+        }
+      } else {
+        category = RESOLVE_SPECULATIVE_SUCCESS;
+        UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.Speculative",
+                                     duration);
+      }
+    } else {
+      if (had_non_speculative_request_) {
+        category = RESOLVE_FAIL;
+        UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveFailureTime", duration);
+        switch (key_.address_family) {
+          case ADDRESS_FAMILY_IPV4:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.IPV4",
+                                         duration);
+            break;
+          case ADDRESS_FAMILY_IPV6:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.IPV6",
+                                         duration);
+            break;
+          case ADDRESS_FAMILY_UNSPECIFIED:
+            UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveSuccessTime.UNSPEC",
+                                         duration);
+            break;
+        }
+      } else {
+        category = RESOLVE_SPECULATIVE_FAIL;
+        UMA_HISTOGRAM_LONG_TIMES_100("Net.DNS.ResolveFailureTime.Speculative",
+                                     duration);
+      }
+    }
+    DCHECK_LT(static_cast<int>(category),
+              static_cast<int>(RESOLVE_MAX));  // Be sure it was set.
+    UMA_HISTOGRAM_ENUMERATION("Net.DNS.ResolveCategory", category, RESOLVE_MAX);
+  }
+
   // Performs Job's last rites. Completes all Requests. Deletes this.
   void CompleteRequests(const HostCache::Entry& entry,
                         base::TimeDelta ttl) {
@@ -1763,8 +1736,10 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
 
     bool did_complete = (entry.error() != ERR_NETWORK_CHANGED) &&
                         (entry.error() != ERR_HOST_RESOLVER_QUEUE_TOO_LARGE);
-    if (did_complete)
+    if (did_complete) {
       resolver_->CacheResult(key_, entry, ttl);
+      RecordJobHistograms(entry.error());
+    }
 
     // Complete all of the requests that were attached to the job and
     // detach them.
@@ -1827,6 +1802,7 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
 
   const base::TimeTicks creation_time_;
   base::TimeTicks priority_change_time_;
+  base::TimeTicks start_time_;
 
   NetLogWithSource net_log_;
 

tools/metrics/histograms/histograms.xml

@@ -3731,6 +3731,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveError" enum="NetErrorCodes">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskError.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Counts of specific error codes returned by DnsTask if a subsequent ProcTask
@@ -3739,6 +3742,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveFail" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken by DnsTask in resolutions that failed. Excludes time
@@ -3747,6 +3753,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveStatus" enum="AsyncDNSResolveStatus">
+  <obsolete>
+    Deprecated as of 9/2017.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Counts of the overall results of using asynchronous DNS in HostResolverImpl.
@@ -3756,6 +3765,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveSuccess" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken by DnsTask in resolutions that succeeded.
@@ -3763,6 +3775,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveSuccess_FAMILY_IPV4" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as AsyncDNS.ResolveSuccess, but limited to pure IPv4 lookups.
@@ -3770,6 +3785,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveSuccess_FAMILY_IPV6" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as AsyncDNS.ResolveSuccess, but limited to pure IPv6 lookups.
@@ -3777,6 +3795,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="AsyncDNS.ResolveSuccess_FAMILY_UNSPEC" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.DnsTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as AsyncDNS.ResolveSuccess, but limited to IPv4/IPv6 lookups.
@@ -14693,6 +14714,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveCategory" enum="ResolutionCategory">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ResolveCategory.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Counts of successes and failures of OS resolutions in various categories.
@@ -14700,6 +14724,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveFail" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken in OS resolutions for actual navigations.  Note that
@@ -14708,21 +14735,33 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveFail_FAMILY_IPV4" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>Same as DNS.ResolveFail, but limited to pure IPv4 lookups.</summary>
 </histogram>
 
 <histogram name="DNS.ResolveFail_FAMILY_IPV6" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>Same as DNS.ResolveFail, but limited to pure IPv6 lookups.</summary>
 </histogram>
 
 <histogram name="DNS.ResolveFail_FAMILY_UNSPEC" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>Same as DNS.ResolveFail, but limited to IPv4/IPv6 lookups.</summary>
 </histogram>
 
 <histogram name="DNS.ResolveSpeculativeFail" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskFail.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken in speculative OS resolutions.  Note that cached OS
@@ -14731,6 +14770,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveSpeculativeSuccess" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken in speculative OS resolution that succeeded.  Note
@@ -14739,6 +14781,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveSuccess" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Duration of time taken in OS resolutions that succeeded and were requested
@@ -14748,6 +14793,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveSuccess_FAMILY_IPV4" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as DNS.ResolveSuccess, but limited to pure IPv4 lookups.
@@ -14755,6 +14803,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveSuccess_FAMILY_IPV6" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as DNS.ResolveSuccess, but limited to pure IPv6 lookups.
@@ -14762,6 +14813,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="DNS.ResolveSuccess_FAMILY_UNSPEC" units="ms">
+  <obsolete>
+    Deprecated as of 9/2017. Replaced by Net.DNS.ProcTaskSuccess.
+  </obsolete>
   <owner>mgersh@chromium.org</owner>
   <summary>
     Same as DNS.ResolveSuccess, but limited to IPv4/IPv6 lookups.
@@ -39593,6 +39647,29 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Net.DNS.DnsTask.Errors" enum="NetErrorCodes">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Counts of specific error codes returned by DnsTask if a subsequent ProcTask
+    succeeded.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.DnsTask.FailureTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by DnsTask in resolutions that failed. Excludes time
+    spent in the subsequent fallback.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.DnsTask.SuccessTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by DnsTask in resolutions that succeeded.
+  </summary>
+</histogram>
+
 <histogram name="Net.DNS.JobQueueTime" units="ms">
   <owner>mgersh@chromium.org</owner>
   <summary>
@@ -39610,6 +39687,48 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Net.DNS.ProcTask.FailureTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by ProcTask in resolutions that failed.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.ProcTask.SuccessTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by ProcTask in resolutions that succeeded.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.ResolveCategory" enum="ResolutionCategory">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Whether a DNS resolution (single HostResolverImpl::Job) succeeded or failed,
+    and whether it was speculative.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.ResolveFailureTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by HostResolverImpl::Job in resolutions that failed.
+    This is the time to resolve a hostname from start to finish. The main
+    histogram and by-priority versions exclude speculative requests, which are
+    recorded in the _speculative version.
+  </summary>
+</histogram>
+
+<histogram name="Net.DNS.ResolveSuccessTime" units="ms">
+  <owner>mgersh@chromium.org</owner>
+  <summary>
+    Duration of time taken by HostResolverImpl::Job in resolutions that
+    succeeded. This is the time to resolve a hostname from start to finish. The
+    main histogram and by-priority versions exclude speculative requests, which
+    are recorded in the _speculative version.
+  </summary>
+</histogram>
+
 <histogram name="Net.DNS.TotalTime" units="ms">
   <owner>mgersh@chromium.org</owner>
   <summary>
@@ -98052,6 +98171,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <affected-histogram name="Net.BidirectionalStream.TimeToSendStart"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="Net.DNS.AddressFamily" separator=".">
+  <suffix name="IPV4" label="Requests for ADDRESS_FAMILY_IPV4."/>
+  <suffix name="IPV6" label="Requests for ADDRESS_FAMILY_IPV6."/>
+  <suffix name="UNSPEC" label="Requests for ADDRESS_FAMILY_UNSPEC."/>
+  <affected-histogram name="Net.DNS.ResolveFailureTime"/>
+  <affected-histogram name="Net.DNS.ResolveSuccessTime"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="Net.DNS.Priorities" separator=".">
   <suffix name="THROTTLED" label="Jobs with priority THROTTLED."/>
   <suffix name="IDLE" label="Jobs with priority IDLE."/>
@@ -98065,6 +98192,8 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram_suffixes name="Net.DNS.Speculative" separator=".">
   <suffix name="Speculative" label="Speculative resolutions only."/>
+  <affected-histogram name="Net.DNS.ResolveFailureTime"/>
+  <affected-histogram name="Net.DNS.ResolveSuccessTime"/>
   <affected-histogram name="Net.DNS.TotalTime"/>
   <affected-histogram name="Net.DNS.TotalTimeNotCached"/>
 </histogram_suffixes>