[SPARK-39973][CORE] Suppress error logs when the number of timers is set to 0

core/src/main/scala/org/apache/spark/internal/config/package.scala

@@ -931,8 +931,12 @@ package object config {
   private[spark] val LISTENER_BUS_METRICS_MAX_LISTENER_CLASSES_TIMED =
     ConfigBuilder("spark.scheduler.listenerbus.metrics.maxListenerClassesTimed")
       .internal()
+      .doc("The number of listeners that have timers to track the elapsed time of" +
+        "processing events. If 0 is set, disables this feature. If -1 is set," +
+        "it sets no limit to the number.")
       .version("2.3.0")
       .intConf
+      .checkValue(_ >= -1, "The number of listeners should be larger than -1.")
       .createWithDefault(128)
 
   private[spark] val LISTENER_BUS_LOG_SLOW_EVENT_ENABLED =

core/src/main/scala/org/apache/spark/scheduler/LiveListenerBus.scala

@@ -292,10 +292,14 @@ private[spark] class LiveListenerBusMetrics(conf: SparkConf)
       val maxTimed = conf.get(LISTENER_BUS_METRICS_MAX_LISTENER_CLASSES_TIMED)
       perListenerClassTimers.get(className).orElse {
         if (perListenerClassTimers.size == maxTimed) {
-          logError(s"Not measuring processing time for listener class $className because a " +
-            s"maximum of $maxTimed listener classes are already timed.")
+          if (maxTimed != 0) {
+            // Explicitly disabled.
+            logError(s"Not measuring processing time for listener class $className because a " +
+              s"maximum of $maxTimed listener classes are already timed.")
+          }
           None
         } else {
+          // maxTimed is either -1 (no limit), or an explicit number.
           perListenerClassTimers(className) =
             metricRegistry.timer(MetricRegistry.name("listenerProcessingTime", className))
           perListenerClassTimers.get(className)

core/src/test/scala/org/apache/spark/scheduler/SparkListenerSuite.scala

@@ -599,6 +599,22 @@ class SparkListenerSuite extends SparkFunSuite with LocalSparkContext with Match
     assert(bus.getQueueCapacity(EVENT_LOG_QUEUE) == Some(2))
   }
 
+  test("SPARK-39973: Suppress error logs when the number of timers is set to 0") {
+    sc = new SparkContext(
+      "local",
+      "SparkListenerSuite",
+      new SparkConf().set(
+        LISTENER_BUS_METRICS_MAX_LISTENER_CLASSES_TIMED.key, 0.toString))
+    val testAppender = new LogAppender("Error logger for timers")
+    withLogAppender(testAppender) {
+      sc.addSparkListener(new SparkListener { })
+      sc.addSparkListener(new SparkListener { })
+    }
+    assert(!testAppender.loggingEvents
+      .exists(_.getMessage.getFormattedMessage.contains(
+        "Not measuring processing time for listener")))
+  }
+
   /**
    * Assert that the given list of numbers has an average that is greater than zero.
    */