The chromoting client logs connection statistics to the server.

remoting/webapp/me2mom/server_log_entry.js

Index: remoting/webapp/me2mom/server_log_entry.js
diff --git a/remoting/webapp/me2mom/server_log_entry.js b/remoting/webapp/me2mom/server_log_entry.js
index 892a91a871f8dd9935c035bd970170e3b09e8d4e..c60f4e90b811ff08da6d07899cb4ef06ecf58e16 100644
--- a/remoting/webapp/me2mom/server_log_entry.js
+++ b/remoting/webapp/me2mom/server_log_entry.js
@@ -94,6 +94,22 @@ remoting.ServerLogEntry.prototype.getValueForConnectionError =
 }
 
 /** @private */
+remoting.ServerLogEntry.prototype.VALUE_EVENT_NAME_CONNECTION_STATISTICS_ =
+    "connection-statistics";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_VIDEO_BANDWIDTH_ = "video-bandwidth";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_CAPTURE_LATENCY_ = "capture-latency";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_ENCODE_LATENCY_ = "encode-latency";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_DECODE_LATENCY_ = "decode-latency";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_RENDER_LATENCY_ = "render-latency";
+/** @private */
+remoting.ServerLogEntry.prototype.KEY_ROUNDTRIP_LATENCY_ = "roundtrip-latency";

[Jamie, 2011/12/09 19:47:56]

Why not reuse the keys from ClientSession?

[simonmorris, 2011/12/09 21:12:12]

Because I want to be able to look down the list of keys
and verify that they match the keys that the server handles.

Also, I don't want a change in the ClientSession keys
to inadvertently change the keys sent to the server,
which would then be ignored.

+
+/** @private */
 remoting.ServerLogEntry.prototype.KEY_OS_NAME_ = 'os-name';
 /** @private */
 remoting.ServerLogEntry.prototype.VALUE_OS_NAME_WINDOWS_ = 'Windows';
@@ -142,6 +158,17 @@ remoting.ServerLogEntry.prototype.toStanza = function() {
 };
 
 /**
+ * Prints this object on the debug log.
+ *
+ * @param {number} indentLevel the indentation level of each field
+ */
+remoting.ServerLogEntry.prototype.toDebugLog = function(indentLevel) {
+  for (var key in this.dict) {
+    remoting.debug.logIndent(indentLevel, key + ': ' + this.dict[key]);
+  }

[Jamie, 2011/12/09 19:47:56]

It might be better to log these on a single line, since they're all closely
related.

[simonmorris, 2011/12/09 21:12:12]

Done.

+};
+
+/**
  * Makes a log entry for a change of client session state.
  *
  * @param {remoting.ClientSession.State} state
@@ -162,6 +189,58 @@ remoting.ServerLogEntry.prototype.makeClientSessionStateChange =
 };
 
 /**
+ * Makes a log entry for a set of connection statistics.
+ * Returns null if all the statistics were zero.
+ *
+ * @param {remoting.StatsAccumulator} statsAccumulator
+ * @return {?remoting.ServerLogEntry}
+ */
+remoting.ServerLogEntry.prototype.makeStats = function(statsAccumulator) {

[Jamie, 2011/12/09 19:47:56]

I don't think this (or the previous method) belongs in the prototype; they're
basically 'static' factory methods.

[simonmorris, 2011/12/09 21:12:12]

Done.

+  var entry = new remoting.ServerLogEntry();
+  entry.set(this.KEY_ROLE_, this.VALUE_ROLE_CLIENT_);
+  entry.set(this.KEY_EVENT_NAME_, this.VALUE_EVENT_NAME_CONNECTION_STATISTICS_);
+  var nonZero = false;
+  nonZero |= entry.addStatsField(
+      this.KEY_VIDEO_BANDWIDTH_,
+      remoting.ClientSession.STATS_KEY_VIDEO_BANDWIDTH, statsAccumulator);
+  nonZero |= entry.addStatsField(
+      this.KEY_CAPTURE_LATENCY_,
+      remoting.ClientSession.STATS_KEY_CAPTURE_LATENCY, statsAccumulator);
+  nonZero |= entry.addStatsField(
+      this.KEY_ENCODE_LATENCY_,
+      remoting.ClientSession.STATS_KEY_ENCODE_LATENCY, statsAccumulator);
+  nonZero |= entry.addStatsField(
+      this.KEY_DECODE_LATENCY_,
+      remoting.ClientSession.STATS_KEY_DECODE_LATENCY, statsAccumulator);
+  nonZero |= entry.addStatsField(
+      this.KEY_RENDER_LATENCY_,
+      remoting.ClientSession.STATS_KEY_RENDER_LATENCY, statsAccumulator);
+  nonZero |= entry.addStatsField(
+      this.KEY_ROUNDTRIP_LATENCY_,
+      remoting.ClientSession.STATS_KEY_ROUNDTRIP_LATENCY, statsAccumulator);
+  if (nonZero) {
+    return entry;
+  }
+  return null;
+};
+
+/**
+ * Adds one connection statistic to a log entry.
+ *
+ * @private
+ * @param {string} entryKey
+ * @param {string} statsKey
+ * @param {remoting.StatsAccumulator} statsAccumulator
+ * @return {boolean} whether the statistic is non-zero
+ */
+remoting.ServerLogEntry.prototype.addStatsField = function(
+    entryKey, statsKey, statsAccumulator) {
+  var val = statsAccumulator.calcMean(statsKey);
+  this.set(entryKey, val.toString());
+  return (val != 0);
+};
+
+/**
  * Adds an ID field to this log entry.
  *
  * @param {string} id