SimpleCache: histogram queuing delays and I/O portion of more ops.

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 f5f47285828c66553d647aae2c867d072cdf2777..47cf35192117ed1a191150a0bf3bd7a669c950c1 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -67416,11 +67416,35 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
-<histogram name="SimpleCache.DiskOpenLatency" units="ms">
+<histogram base="true" name="SimpleCache.DiskCloseLatency" units="ms">
+  <owner>morlovich@chromium.org</owner>
+  <summary>
+    The time to close (write out footers and close the file) the cache entry on
+    disk. Includes only successful operations.
+  </summary>
+</histogram>
+
+<histogram base="true" name="SimpleCache.DiskCreateLatency" units="ms">
+  <owner>morlovich@chromium.org</owner>
+  <summary>
+    The time to access (open for creation and write initial headers) the cache
+    entry on disk. Includes only successful operations.
+  </summary>
+</histogram>
+
+<histogram base="true" name="SimpleCache.DiskOpenLatency" units="ms">
   <owner>rdsmith@chromium.org</owner>
   <summary>
     The time to access (open and read headers from all files) the cache entry on
-    disk.
+    disk. Includes only successful operations.
+  </summary>
+</histogram>
+
+<histogram base="true" name="SimpleCache.DiskWriteLatency" units="ms">
+  <owner>morlovich@chromium.org</owner>
+  <summary>
+    The time to write a chunk to the cache entry on disk. Includes only
+    successful operations.
   </summary>
 </histogram>
 
@@ -67837,6 +67861,22 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram base="true" name="SimpleCache.QueueLatency.CreateEntry" units="ms">
+  <owner>morlovich@chromium.org</owner>
+  <summary>
+    Delay between when the I/O portion of CreateEntry is enqueued and when its
+    execution begins.
+  </summary>
+</histogram>
+
+<histogram base="true" name="SimpleCache.QueueLatency.OpenEntry" units="ms">
+  <owner>morlovich@chromium.org</owner>
+  <summary>
+    Delay between when the I/O portion of OpenEntry is enqueued and when its
+    execution begins.
+  </summary>
+</histogram>
+
 <histogram base="true" name="SimpleCache.ReadIsParallelizable"
     enum="SimpleCacheReadParallelizable">
   <owner>gavinp@chromium.org</owner>
@@ -119799,6 +119839,10 @@ from previous Chrome versions.
   <affected-histogram name="SimpleCache.CheckCRCResult"/>
   <affected-histogram name="SimpleCache.CreationToIndex"/>
   <affected-histogram name="SimpleCache.CreationToIndexFail"/>
+  <affected-histogram name="SimpleCache.DiskCloseLatency"/>
+  <affected-histogram name="SimpleCache.DiskCreateLatency"/>
+  <affected-histogram name="SimpleCache.DiskOpenLatency"/>
+  <affected-histogram name="SimpleCache.DiskWriteLatency"/>
   <affected-histogram name="SimpleCache.EntryCreatedAndStream2Omitted"/>
   <affected-histogram name="SimpleCache.EntryCreationResult"/>
   <affected-histogram name="SimpleCache.EntryCreationTime"/>
@@ -119849,6 +119893,8 @@ from previous Chrome versions.
   <affected-histogram name="SimpleCache.MaxCacheSizeOnInit"/>
   <affected-histogram name="SimpleCache.OpenEntryIndexState"/>
   <affected-histogram name="SimpleCache.PercentFullOnInit"/>
+  <affected-histogram name="SimpleCache.QueueLatency.CreateEntry"/>
+  <affected-histogram name="SimpleCache.QueueLatency.OpenEntry"/>
   <affected-histogram name="SimpleCache.ReadIsParallelizable"/>
   <affected-histogram name="SimpleCache.ReadResult"/>
   <affected-histogram name="SimpleCache.StaleIndexExtraEntryCount"/>