From 5e64f501dbbb151ca8d92b9f35ffe0b7b8a9805f Mon Sep 17 00:00:00 2001
From: Andrew Choi <li_andchoi@microsoft.com>
Date: Fri, 3 Jul 2020 13:36:10 -0700
Subject: [PATCH] =?UTF-8?q?Avoid=20NaN=20in=20Commit=20Offset=20Failure=20?=
 =?UTF-8?q?Rate=20OffsetCommitServiceMetrics=20by=E2=80=A6=20(#292)?=
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* Avoid NaN in Commit Offset Failure Rate OffsetCommitServiceMetrics by initializing with a zero only when instantiating.
Signed-off-by: Andrew Choi <li_andchoi@microsoft.com>
❄️
---
 .../monitor/services/metrics/OffsetCommitServiceMetrics.java    | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/main/java/com/linkedin/xinfra/monitor/services/metrics/OffsetCommitServiceMetrics.java b/src/main/java/com/linkedin/xinfra/monitor/services/metrics/OffsetCommitServiceMetrics.java
index 3e4ca58d..1fad2177 100644
--- a/src/main/java/com/linkedin/xinfra/monitor/services/metrics/OffsetCommitServiceMetrics.java
+++ b/src/main/java/com/linkedin/xinfra/monitor/services/metrics/OffsetCommitServiceMetrics.java
@@ -51,6 +51,8 @@ public OffsetCommitServiceMetrics(final Metrics metrics, final Map<String, Strin
         new Total());
 
     _offsetCommitFailSensor = metrics.sensor(FAILURE_SENSOR_NAME);
+    /* NaN will persist as long as no record is submitted to the failure sensor.
+       we'll continue with NaN for now since we'd rather that the Sensor itself is a true and unaltered record of what values it recorded. */
     _offsetCommitFailSensor.add(new MetricName(FAILURE_RATE_METRIC, METRIC_GROUP_NAME,
         "The failure rate of group coordinator accepting consumer offset commit requests.", tags), new Avg());
     _offsetCommitFailSensor.add(new MetricName(FAILURE_METRIC_TOTAL, METRIC_GROUP_NAME,