HBASE-27892 Report memstore on-heap and off-heap size as jmx metrics (#5308)

Signed-off-by: Viraj Jasani <vjasani@apache.org>

Author: jinggou

hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSource.java

@@ -233,6 +233,10 @@ public interface MetricsRegionServerSource extends BaseSource, JvmPauseMonitorSo
   String MAX_COMPACTED_STORE_FILE_REF_COUNT = "maxCompactedStoreFileRefCount";
   String MEMSTORE_SIZE = "memStoreSize";
   String MEMSTORE_SIZE_DESC = "Size of the memstore";
+  String MEMSTORE_HEAP_SIZE = "memStoreHeapSize";
+  String MEMSTORE_HEAP_SIZE_DESC = "On-heap Size of the memstore";
+  String MEMSTORE_OFFHEAP_SIZE = "memStoreOffHeapSize";
+  String MEMSTORE_OFFHEAP_SIZE_DESC = "Off-heap Size of the memstore";
   String STOREFILE_SIZE = "storeFileSize";
   String MAX_STORE_FILE_AGE = "maxStoreFileAge";
   String MIN_STORE_FILE_AGE = "minStoreFileAge";

hbase-hadoop2-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceImpl.java

@@ -479,6 +479,10 @@ private MetricsRecordBuilder addGaugesToMetricsRecordBuilder(MetricsRecordBuilde
       .addGauge(Interns.info(MAX_STOREFILE_COUNT, MAX_STOREFILE_COUNT_DESC),
         rsWrap.getMaxStoreFiles())
       .addGauge(Interns.info(MEMSTORE_SIZE, MEMSTORE_SIZE_DESC), rsWrap.getMemStoreSize())
+      .addGauge(Interns.info(MEMSTORE_HEAP_SIZE, MEMSTORE_HEAP_SIZE_DESC),
+        rsWrap.getOnHeapMemStoreSize())
+      .addGauge(Interns.info(MEMSTORE_OFFHEAP_SIZE, MEMSTORE_OFFHEAP_SIZE_DESC),
+        rsWrap.getOffHeapMemStoreSize())
       .addGauge(Interns.info(STOREFILE_SIZE, STOREFILE_SIZE_DESC), rsWrap.getStoreFileSize())
       .addGauge(Interns.info(MAX_STORE_FILE_AGE, MAX_STORE_FILE_AGE_DESC),
         rsWrap.getMaxStoreFileAge())

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsRegionServer.java

@@ -83,6 +83,8 @@ public void testWrapperSource() {
     HELPER.assertGauge("hlogFileSize", 1024000, serverSource);
     HELPER.assertGauge("storeFileCount", 300, serverSource);
     HELPER.assertGauge("memstoreSize", 1025, serverSource);
+    HELPER.assertGauge("memstoreHeapSize", 500, serverSource);
+    HELPER.assertGauge("memstoreOffHeapSize", 600, serverSource);
     HELPER.assertGauge("storeFileSize", 1900, serverSource);
     HELPER.assertCounter("totalRequestCount", 899, serverSource);
     HELPER.assertCounter("totalRowActionRequestCount",