tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index afbb320f6169c03e5ba62096ab69e9026ba728cb..eae09e75ed01ea8b8ec0063ac5304dc47911a146 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -13683,6 +13683,61 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Download.ParallelDownloadCounts"
+    enum="ParallelDownloadCountType">
+  <owner>qinmin@chromium.org</owner>
+  <summary>
+    Various counts for download that uses parallel requests, including started,
+    completed, cancelled and interrupted.
+  </summary>
+</histogram>

[Ilya Sherman, 2017/03/24 00:52:59]

Could you use a histogram_suffixes element to reduce repeated text in this file?

[qinmin, 2017/03/24 19:54:40]

Done.

+
+<histogram name="Download.ParallelDownloadInterruptedAtEndReason"
+    enum="InterruptReason">
+  <owner>qinmin@chromium.org</owner>
+  <summary>
+    The reason that a download was interrupted at the *end* of a download (when
+    the number of bytes is known). This is only triggered when the total content
+    size is known before any bytes are transferred, such as when a
+    Content-Length header is supplied.
+  </summary>
+</histogram>
+
+<histogram name="Download.ParallelDownloadInterruptedReason"
+    enum="InterruptReason">
+  <owner>qinmin@chromium.org</owner>
+  <summary>The reason that a download was interrupted.</summary>
+</histogram>
+
+<histogram name="Download.ParallelDownloadInterruptedReceivedSizeK" units="KB">
+  <owner>qinmin@chromium.org</owner>
+  <summary>
+    The number of kilobytes received for a download at the time it is
+    interrupted.
+  </summary>
+</histogram>
+
+<histogram name="Download.ParallelDownloadInterruptedTotalSizeK" units="KB">
+  <owner>qinmin@chromium.org</owner>
+  <summary>
+    The reported total size in kilobytes for a download at the time it is
+    interrupted. This is essentially the size reported by the Content-Length
+    header. If no size is specified up-front, it is not recorded in the
+    histogram. For example, a download transferred with chunked encoding will
+    not be recorded.
+  </summary>
+</histogram>
+
+<histogram name="Download.ParallelDownloadInterruptedUnderrunBytes">
+  <owner>qinmin@chromium.org</owner>
+  <summary>
+    The excessive number of bytes which have been received at the time that a
+    download is interrupted. This is only triggered when the total content size
+    is known before any bytes are transferred, such as when a Content-Length
+    header is supplied.
+  </summary>
+</histogram>
+
 <histogram name="Download.PotentialBandwidth" units="Bytes/second">
   <obsolete>
     Deprecated January 2017.
@@ -87919,7 +87974,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="15" label="Supports ranges and strong ETag (Obsolete 11/2013)"/>
   <int value="16" label="No WebContents at interruption"/>
   <int value="17" label="Supports ranges and strong validation"/>
-  <int value="18" label="Uses parallel requests"/>
+  <int value="18" label="Uses parallel requests (Obsolete 3/2017)"/>
 </enum>
 
 <enum name="DownloadDatabaseRecordDroppedType" type="int">
@@ -104668,6 +104723,14 @@ from previous Chrome versions.
   <int value="1" label="HRTF"/>
 </enum>
 
+<enum name="ParallelDownloadCountType" type="int">
+  <int value="0" label="Completed"/>
+  <int value="1" label="Cancelled"/>
+  <int value="2" label="Started"/>
+  <int value="3" label="Interrupted"/>
+  <int value="4" label="Interrupted at End of Download"/>
+</enum>
+
 <enum name="ParsedCookieStatus" type="int">
   <obsolete>
     Deprecated as of 9/2013. Experiment to measure control characters in cookies