From d48133fbaa1e78a87ecb01199ed22108ec52e851 Mon Sep 17 00:00:00 2001
From: Lalit <labhas@microsoft.com>
Date: Wed, 23 Oct 2024 20:56:59 -0700
Subject: [PATCH 1/3] metrics-sdk-error

---
 .../metrics/internal/exponential_histogram.rs | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
index c23b441663..4907f91c25 100644
--- a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
+++ b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
@@ -1,7 +1,7 @@
 use std::{collections::HashMap, f64::consts::LOG2_E, sync::Mutex, time::SystemTime};
 
 use once_cell::sync::Lazy;
-use opentelemetry::{metrics::MetricsError, KeyValue};
+use opentelemetry::{otel_debug, KeyValue};
 
 use crate::{
     metrics::data::{self, Aggregation, Temporality},
@@ -100,9 +100,20 @@ impl<T: Number> ExpoHistogramDataPoint<T> {
             if (self.scale - scale_delta as i8) < EXPO_MIN_SCALE {
                 // With a scale of -10 there is only two buckets for the whole range of f64 values.
                 // This can only happen if there is a max size of 1.
-                opentelemetry::global::handle_error(MetricsError::Other(
-                    "exponential histogram scale underflow".into(),
-                ));
+
+                // TODO - to check if this should be logged as an error if this is auto-recoverable.
+                otel_debug!(
+                    name: "ExponentialHistogramDataPoint.Scale.Underflow",
+                    current_scale = self.scale,
+                    scale_delta = scale_delta,
+                    max_size = self.max_size,
+                    min_scale = EXPO_MIN_SCALE,
+                    record_min_max = self.record_min_max,
+                    record_sum = self.record_sum,
+                    value = format!("{:?}", v),
+                    error = "The measurement will be dropped due to scale underflow. Check the histogram configuration"
+                );
+
                 return;
             }
             // Downscale

From bde6dd194b0adaf940191e9325a19da1847d4341 Mon Sep 17 00:00:00 2001
From: Lalit Kumar Bhasin <lalit_fin@yahoo.com>
Date: Thu, 24 Oct 2024 09:38:09 -0700
Subject: [PATCH 2/3] Update
 opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs

Co-authored-by: Cijo Thomas <cithomas@microsoft.com>
---
 opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
index 4907f91c25..18160fbf17 100644
--- a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
+++ b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
@@ -111,7 +111,7 @@ impl<T: Number> ExpoHistogramDataPoint<T> {
                     record_min_max = self.record_min_max,
                     record_sum = self.record_sum,
                     value = format!("{:?}", v),
-                    error = "The measurement will be dropped due to scale underflow. Check the histogram configuration"
+                    message = "The measurement will be dropped due to scale underflow. Check the histogram configuration"
                 );
 
                 return;

From 4bab7f5d122edd83b6646021ee2cedb6ec604a5c Mon Sep 17 00:00:00 2001
From: Lalit Kumar Bhasin <lalit_fin@yahoo.com>
Date: Thu, 24 Oct 2024 09:50:48 -0700
Subject: [PATCH 3/3] review comment

---
 opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
index 18160fbf17..e85e0ece55 100644
--- a/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
+++ b/opentelemetry-sdk/src/metrics/internal/exponential_histogram.rs
@@ -108,8 +108,6 @@ impl<T: Number> ExpoHistogramDataPoint<T> {
                     scale_delta = scale_delta,
                     max_size = self.max_size,
                     min_scale = EXPO_MIN_SCALE,
-                    record_min_max = self.record_min_max,
-                    record_sum = self.record_sum,
                     value = format!("{:?}", v),
                     message = "The measurement will be dropped due to scale underflow. Check the histogram configuration"
                 );