Clarify slow cluster-state log messages (#38302)

The message `... took [31s] above the warn threshold of 30s` suggests
incorrectly that the task took 61 seconds. This commit adds the clarifying
words `which is`.

Author: DaveCTurner

server/src/main/java/org/elasticsearch/cluster/service/ClusterApplierService.java

@@ -517,7 +517,7 @@ public void onSuccess(String source) {
 
     protected void warnAboutSlowTaskIfNeeded(TimeValue executionTime, String source) {
         if (executionTime.getMillis() > slowTaskLoggingThreshold.getMillis()) {
-            logger.warn("cluster state applier task [{}] took [{}] above the warn threshold of {}", source, executionTime,
+            logger.warn("cluster state applier task [{}] took [{}] which is above the warn threshold of {}", source, executionTime,
                 slowTaskLoggingThreshold);
         }
     }

server/src/main/java/org/elasticsearch/cluster/service/ClusterService.java

@@ -19,8 +19,6 @@
 
 package org.elasticsearch.cluster.service;
 
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.ClusterStateApplier;
@@ -45,8 +43,6 @@
 import java.util.Map;
 
 public class ClusterService extends AbstractLifecycleComponent {
-    private static final Logger logger = LogManager.getLogger(ClusterService.class);
-
     private final MasterService masterService;
 
     private final ClusterApplierService clusterApplierService;

server/src/main/java/org/elasticsearch/cluster/service/MasterService.java

@@ -569,7 +569,7 @@ public TimeValue ackTimeout() {
 
     protected void warnAboutSlowTaskIfNeeded(TimeValue executionTime, String source) {
         if (executionTime.getMillis() > slowTaskLoggingThreshold.getMillis()) {
-            logger.warn("cluster state update task [{}] took [{}] above the warn threshold of {}", source, executionTime,
+            logger.warn("cluster state update task [{}] took [{}] which is above the warn threshold of {}", source, executionTime,
                 slowTaskLoggingThreshold);
         }
     }

server/src/test/java/org/elasticsearch/cluster/service/ClusterApplierServiceTests.java

@@ -195,19 +195,19 @@ public void testLongClusterStateUpdateLogging() throws Exception {
                         "test1 shouldn't see because setting is too low",
                         ClusterApplierService.class.getCanonicalName(),
                         Level.WARN,
-                        "*cluster state applier task [test1] took [*] above the warn threshold of *"));
+                        "*cluster state applier task [test1] took [*] which is above the warn threshold of *"));
         mockAppender.addExpectation(
                 new MockLogAppender.SeenEventExpectation(
                         "test2",
                         ClusterApplierService.class.getCanonicalName(),
                         Level.WARN,
-                        "*cluster state applier task [test2] took [32s] above the warn threshold of *"));
+                        "*cluster state applier task [test2] took [32s] which is above the warn threshold of *"));
         mockAppender.addExpectation(
                 new MockLogAppender.SeenEventExpectation(
                         "test4",
                         ClusterApplierService.class.getCanonicalName(),
                         Level.WARN,
-                        "*cluster state applier task [test3] took [34s] above the warn threshold of *"));
+                        "*cluster state applier task [test3] took [34s] which is above the warn threshold of *"));
 
         Logger clusterLogger = LogManager.getLogger(ClusterApplierService.class);
         Loggers.addAppender(clusterLogger, mockAppender);

server/src/test/java/org/elasticsearch/cluster/service/MasterServiceTests.java

@@ -652,25 +652,25 @@ public void testLongClusterStateUpdateLogging() throws Exception {
                 "test1 shouldn't see because setting is too low",
                 MasterService.class.getCanonicalName(),
                 Level.WARN,
-                "*cluster state update task [test1] took [*] above the warn threshold of *"));
+                "*cluster state update task [test1] took [*] which is above the warn threshold of *"));
         mockAppender.addExpectation(
             new MockLogAppender.SeenEventExpectation(
                 "test2",
                 MasterService.class.getCanonicalName(),
                 Level.WARN,
-                "*cluster state update task [test2] took [32s] above the warn threshold of *"));
+                "*cluster state update task [test2] took [32s] which is above the warn threshold of *"));
         mockAppender.addExpectation(
             new MockLogAppender.SeenEventExpectation(
                 "test3",
                 MasterService.class.getCanonicalName(),
                 Level.WARN,
-                "*cluster state update task [test3] took [33s] above the warn threshold of *"));
+                "*cluster state update task [test3] took [33s] which is above the warn threshold of *"));
         mockAppender.addExpectation(
             new MockLogAppender.SeenEventExpectation(
                 "test4",
                 MasterService.class.getCanonicalName(),
                 Level.WARN,
-                "*cluster state update task [test4] took [34s] above the warn threshold of *"));
+                "*cluster state update task [test4] took [34s] which is above the warn threshold of *"));
 
         Logger clusterLogger = LogManager.getLogger(MasterService.class);
         Loggers.addAppender(clusterLogger, mockAppender);