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 e4c9971a06483a498240fd0aa61f753ed4615045..de94a5fa932e646f05020be2f1c911cf13881547 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -29869,24 +29869,6 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
-<histogram name="OfflinePages.DeletePage.TotalPageSizeAsPercentageOfFreeSpace"
-    units="%">
-  <owner>fgorski@chromium.org</owner>
-  <owner>jianli@chromium.org</owner>
-  <summary>
-    The percentage of space taken by offline pages from the free space that
-    could be available, if the feature was not present. I.e. considering
-    situation where the user has: Free Space, Offline content, other apps and
-    data. This is a percentage of: Offline content / (Offline content + Free
-    Space).
-
-    The value will be recorded after user deletes a single or multiple offline
-    pages. In case pages are removed in bulk, this value will be reported once.
-    This value is only reported with deleting, as we are trying to infer if lack
-    of free space might have caused the user to delete.
-  </summary>
-</histogram>
-
 <histogram name="OfflinePages.DeletePage.LastOpenToCreated" units="minutes">
   <owner>jianli@chromium.org</owner>
   <summary>
@@ -29907,6 +29889,24 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="OfflinePages.DeletePage.TotalPageSizeAsPercentageOfFreeSpace"

[Mark P, 2015/11/16 20:31:21]

This move change should go away after you sync and rebase.

[afakhry, 2015/11/16 22:33:49]

Done.

+    units="%">
+  <owner>fgorski@chromium.org</owner>
+  <owner>jianli@chromium.org</owner>
+  <summary>
+    The percentage of space taken by offline pages from the free space that
+    could be available, if the feature was not present. I.e. considering
+    situation where the user has: Free Space, Offline content, other apps and
+    data. This is a percentage of: Offline content / (Offline content + Free
+    Space).
+
+    The value will be recorded after user deletes a single or multiple offline
+    pages. In case pages are removed in bulk, this value will be reported once.
+    This value is only reported with deleting, as we are trying to infer if lack
+    of free space might have caused the user to delete.
+  </summary>
+</histogram>
+
 <histogram name="OfflinePages.DeletePageResult"
     enum="OfflinePagesDeletePageResult">
   <owner>jianli@chromium.org</owner>
@@ -38950,6 +38950,42 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ResourceReporter.BrowserProcess.CpuUsage"
+    enum="ResourceReporterCpuUsage">
+  <owner>afakhry@chromium.org</owner>
+  <summary>
+    The cpu usage rage reported for the browser process when the system is under

[Mark P, 2015/11/16 20:31:21]

rage?
rate?  range?

ditto below

[afakhry, 2015/11/16 22:33:49]

range. Done.

+    moderate memory pressure or higher.

[Mark P, 2015/11/16 20:31:21]

Please allude to how this is defined.  For instance, is this absolute memory
usage (depends just on chrome) or memory usage as a percent of all system memory
(again depends just on chrome) or percent or amount of free memory on the system
(which depends on what other apps are open)?

please put the same information in all the relevant histograms.
 

[Mark P, 2015/11/16 20:31:21]

please mention when this is emitted.  On every pageload?  Only on the transition
from not-under-pressure to under-pressure?  etc?

ditto all histograms below

[Mark P, 2015/11/16 20:31:21]

how is cpu usage measured on multi-core machines?  Is it amount as a percent of
the sum of processing power of all cores?

[afakhry, 2015/11/16 22:33:49]

It is a percent of the total CPU power. So if a process is using 100% of a core
in a dual-core CPU, then this process is actually using 50%.

[afakhry, 2015/11/16 22:33:49]

It's the total percentage of memory used by the system (chrome, apps,
extensions, and all processes). The thresholds defining moderate and critical
memory pressures are dependent on a flag.

Done.

[afakhry, 2015/11/16 22:33:49]

Done.

[Mark P, 2015/11/16 23:42:18]

Acknowledged.  The current explanation is fine then.

+  </summary>
+</histogram>
+
+<histogram name="ResourceReporter.BrowserProcess.MemoryUsage"
+    enum="ResourceReporterMemoryUsage">
+  <owner>afakhry@chromium.org</owner>
+  <summary>
+    The memory usage range reported for the browser process when the system is
+    under moderate memory pressure or higher.
+  </summary>
+</histogram>
+
+<histogram name="ResourceReporter.GpuProcess.CpuUsage"

[Mark P, 2015/11/16 20:31:21]

Doesn't it make more sense to call GpuUsage, not CpuUsage, as the description
implies that it's the processor in the GPU chip?

[afakhry, 2015/11/16 22:33:49]

The GPU process runs on the CPU not the GPU.

[Mark P, 2015/11/16 23:42:18]

Ah, silly me confusing GPU process and GPU chip/processor.

+    enum="ResourceReporterCpuUsage">
+  <owner>afakhry@chromium.org</owner>
+  <summary>
+    The cpu usage rage reported for the GPU process when the system is under
+    moderate memory pressure or higher.
+  </summary>
+</histogram>
+
+<histogram name="ResourceReporter.GpuProcess.MemoryUsage"
+    enum="ResourceReporterMemoryUsage">
+  <owner>afakhry@chromium.org</owner>
+  <summary>
+    The memory usage range reported for the GPU process when the system is under

[Mark P, 2015/11/16 20:31:21]

This is system ram, not memory on the GPU, right?  Be clear.

[afakhry, 2015/11/16 22:33:49]

Right. Done.

+    moderate memory pressure or higher.
+  </summary>
+</histogram>
+
 <histogram name="ResourceScheduler.ClientLoadedTime.Active">
   <owner>aiolos@chromium.org</owner>
   <summary>
@@ -72328,6 +72364,22 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="64" label="RESOURCE_STATUS_HEADERS_MISSING"/>
 </enum>
 
+<enum name="ResourceReporterCpuUsage" type="int">
+  <int value="0" label="RANGE_0_TO_10_PERCENT"/>

[Mark P, 2015/11/16 20:31:21]

you don't need ugly enum-like labels here.  Do something reasonable.

[afakhry, 2015/11/16 22:33:49]

I saw other enums in this file using enum-like naming, so I assumed this is the
convention.

+  <int value="1" label="RANGE_10_TO_30_PERCENT"/>
+  <int value="2" label="RANGE_30_TO_60_PERCENT"/>
+  <int value="3" label="RANGE_ABOVE_60_PERCENT"/>
+</enum>
+
+<enum name="ResourceReporterMemoryUsage" type="int">
+  <int value="0" label="RANGE_0_TO_200_MB"/>
+  <int value="1" label="RANGE_200_TO_400_MB"/>
+  <int value="2" label="RANGE_400_TO_600_MB"/>
+  <int value="3" label="RANGE_600_TO_800_MB"/>
+  <int value="4" label="RANGE_800_TO_1_GB"/>
+  <int value="5" label="RANGE_ABOVE_1_GB"/>
+</enum>
+
 <enum name="ResourceType" type="int">
   <int value="0" label="Main resource"/>
   <int value="1" label="Image"/>