diff --git a/system_wrappers/include/metrics.h b/system_wrappers/include/metrics.h
index 13f2483b32..13ed2c936d 100644
--- a/system_wrappers/include/metrics.h
+++ b/system_wrappers/include/metrics.h
@@ -128,9 +128,9 @@
 // Histogram for enumerators (evenly spaced buckets).
 // |boundary| should be above the max enumerator sample.
 #define RTC_HISTOGRAM_ENUMERATION_SPARSE(name, sample, boundary) \
-  RTC_HISTOGRAM_COMMON_BLOCK_SLOW(                               \
+  RTC_HISTOGRAM_COMMON_BLOCK(                                    \
       name, sample,                                              \
-      webrtc::metrics::HistogramFactoryGetEnumeration(name, boundary))
+      webrtc::metrics::SparseHistogramFactoryGetEnumeration(name, boundary))
 
 // Histogram for percentage (evenly spaced buckets).
 #define RTC_HISTOGRAM_PERCENTAGE(name, sample) \
@@ -263,6 +263,11 @@ Histogram* HistogramFactoryGetCountsLinear(const std::string& name,
 Histogram* HistogramFactoryGetEnumeration(const std::string& name,
                                           int boundary);
 
+// Get sparse histogram for enumerators.
+// |boundary| should be above the max enumerator sample.
+Histogram* SparseHistogramFactoryGetEnumeration(const std::string& name,
+                                                int boundary);
+
 // Function for adding a |sample| to a histogram.
 void HistogramAdd(Histogram* histogram_pointer, int sample);
 
diff --git a/system_wrappers/source/metrics_default.cc b/system_wrappers/source/metrics_default.cc
index fbb2956301..7b62c8103f 100644
--- a/system_wrappers/source/metrics_default.cc
+++ b/system_wrappers/source/metrics_default.cc
@@ -247,6 +247,12 @@ Histogram* HistogramFactoryGetEnumeration(const std::string& name,
   return map->GetEnumerationHistogram(name, boundary);
 }
 
+// Our default implementation reuses the non-sparse histogram.
+Histogram* SparseHistogramFactoryGetEnumeration(const std::string& name,
+                                                int boundary) {
+  return HistogramFactoryGetEnumeration(name, boundary);
+}
+
 // Fast path. Adds |sample| to cached |histogram_pointer|.
 void HistogramAdd(Histogram* histogram_pointer, int sample) {
   RtcHistogram* ptr = reinterpret_cast<RtcHistogram*>(histogram_pointer);