diff --git a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs
index d60be1b83bdd8..aec84922437a3 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs
@@ -127,7 +127,7 @@ private void EnableTimer(float pollingIntervalInSeconds)
             Debug.Assert(Monitor.IsEntered(s_counterGroupLock));
             if (pollingIntervalInSeconds <= 0)
             {
-                _pollingIntervalInMilliseconds = 0;
+                DisableTimer();
             }
             else if (_pollingIntervalInMilliseconds == 0 || pollingIntervalInSeconds * 1000 < _pollingIntervalInMilliseconds)
             {
@@ -187,6 +187,7 @@ private void EnableTimer(float pollingIntervalInSeconds)
 
         private void DisableTimer()
         {
+            Debug.Assert(Monitor.IsEntered(s_counterGroupLock));
             _pollingIntervalInMilliseconds = 0;
             s_counterGroupEnabledList?.Remove(this);
         }
@@ -252,7 +253,8 @@ private void OnTimer()
                 {
                     _timeStampSinceCollectionStarted = now;
                     TimeSpan delta = now - _nextPollingTimeStamp;
-                    if (delta > TimeSpan.Zero && _pollingIntervalInMilliseconds > 0)
+                    delta = _pollingIntervalInMilliseconds > delta.TotalMilliseconds ? TimeSpan.FromMilliseconds(_pollingIntervalInMilliseconds) : delta;
+                    if (_pollingIntervalInMilliseconds > 0)
                         _nextPollingTimeStamp += TimeSpan.FromMilliseconds(_pollingIntervalInMilliseconds * Math.Ceiling(delta.TotalMilliseconds / _pollingIntervalInMilliseconds));
                 }
             }