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 5e08392296ed9f521091dc10aeef2b70480646db..89a5ff4322c62bf1116768a6b423d01130a4f7ae 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -11326,6 +11326,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="NCN.CM.FastestRTTOnBluetooth" units="milliseconds">
+  <owner>pauljensen@chromium.org</owner>
+  <summary>
+    Rough estimate of the fastest round-trip-time seen on a Bluetooth
+    connection, before the NetworkChangeNotifier detected a connectivity change.

[Ilya Sherman, 2014/06/03 19:19:16]

Please document when this metric is recorded.  Is it only when the network
changes?  Once per session, for some definition of session?  When a new fastest
RTT is observed?  Something else?

[pauljensen, 2014/06/09 16:17:54]

I thought the "...fastest...seen on a XYZ connection, before the
NetworkChangeNotifier detected a connectivity change." implied that it was
recorded when the NetworkChangeNotifier detected a connectivity change.  If it
were not recorded at the end of the specified time period there would be no way
to know it's the fastest during that period.  Would you like me to make it more
explicit like:
"...seen on a XYZ connection, before the NetworkChangeNotifier detected a
connectivity change at which point the metric is recorded."
Or maybe make it a separate sentence:
"This metric is recorded when the NetworkChangeNotifier detects a connectivity
change.  This will miss data from users whose connection type never changes and
will be biased to users whose connection type changes frequently."

[Ilya Sherman, 2014/06/09 22:14:48]

I'd prefer that you add it as an extra sentence.  It's nice to specifically call
out potential sources of bias in histogram descriptions, so that anyone viewing
the histogram will have a better chance of remembering to watch out for this
bias.

[jkarlin, 2014/06/10 14:25:44]

Done.

+  </summary>
+</histogram>
+
 <histogram name="NCN.CM.FastestRTTOnEthernet" units="milliseconds">
   <owner>pauljensen@chromium.org</owner>
   <summary>
@@ -11383,6 +11391,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="NCN.CM.FirstReadOnBluetooth" units="milliseconds">
+  <owner>pauljensen@chromium.org</owner>
+  <summary>
+    Time between switching to a Bluetooth connection and receiving the first
+    network data.
+  </summary>
+</histogram>
+
 <histogram name="NCN.CM.FirstReadOnEthernet" units="milliseconds">
   <owner>pauljensen@chromium.org</owner>
   <summary>
@@ -11438,6 +11454,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="NCN.CM.KBTransferedOnBluetooth" units="KB">
+  <owner>pauljensen@chromium.org</owner>
+  <summary>
+    How much data was transfered while connected via a Bluetooth connection,
+    before the NetworkChangeNotifier detected a connectivity change.

[Ilya Sherman, 2014/06/03 19:19:16]

Ditto.

[jkarlin, 2014/06/10 14:25:44]

Done.

+  </summary>
+</histogram>
+
 <histogram name="NCN.CM.KBTransferedOnEthernet" units="KB">
   <owner>pauljensen@chromium.org</owner>
   <summary>
@@ -11495,6 +11519,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="NCN.CM.PeakKbpsOnBluetooth" units="Kbps">
+  <owner>pauljensen@chromium.org</owner>
+  <summary>
+    Rough estimate of peak throughput seen on a Bluetooth connection, before the
+    NetworkChangeNotifier detected a connectivity change.

[Ilya Sherman, 2014/06/03 19:19:16]

Ditto.

[jkarlin, 2014/06/10 14:25:44]

Done.

+  </summary>
+</histogram>
+
 <histogram name="NCN.CM.PeakKbpsOnEthernet" units="Kbps">
   <owner>pauljensen@chromium.org</owner>
   <summary>
@@ -11552,6 +11584,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="NCN.CM.TimeOnBluetooth" units="milliseconds">
+  <owner>pauljensen@chromium.org</owner>
+  <summary>
+    How long was spent connected via a Bluetooth connection, before the
+    NetworkChangeNotifier detected a connectivity change.

[Ilya Sherman, 2014/06/03 19:19:16]

Ditto.

[jkarlin, 2014/06/10 14:25:44]

Done.

+  </summary>
+</histogram>
+
 <histogram name="NCN.CM.TimeOnEthernet" units="milliseconds">
   <owner>pauljensen@chromium.org</owner>
   <summary>