HBASE-27159 Emit source metrics for BlockCacheExpressHitPercent (#4830)

Signed-off-by: Andrew Purtell <apurtell@apache.org>

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

@@ -329,12 +329,18 @@ public interface MetricsRegionServerSource extends BaseSource, JvmPauseMonitorSo
   String BLOCK_CACHE_HIT_COUNT_DESC = "Count of the hit on the block cache.";
   String BLOCK_CACHE_PRIMARY_HIT_COUNT = "blockCacheHitCountPrimary";
   String BLOCK_CACHE_PRIMARY_HIT_COUNT_DESC = "Count of hit on primary replica in the block cache.";
+  String BLOCK_CACHE_HIT_CACHING_COUNT = "blockCacheHitCachingCount";
+  String BLOCK_CACHE_HIT_CACHING_COUNT_DESC =
+    "Count of the hit on the block cache, for cacheable requests.";
   String BLOCK_CACHE_MISS_COUNT = "blockCacheMissCount";
   String BLOCK_COUNT_MISS_COUNT_DESC =
     "Number of requests for a block that missed the block cache.";
   String BLOCK_CACHE_PRIMARY_MISS_COUNT = "blockCacheMissCountPrimary";
   String BLOCK_COUNT_PRIMARY_MISS_COUNT_DESC =
     "Number of requests for a block of primary replica that missed the block cache.";
+  String BLOCK_CACHE_MISS_CACHING_COUNT = "blockCacheMissCachingCount";
+  String BLOCK_COUNT_MISS_CACHING_COUNT_DESC =
+    "Number of requests for a block that missed the block cache, for cacheable requests.";
   String BLOCK_CACHE_EVICTION_COUNT = "blockCacheEvictionCount";
   String BLOCK_CACHE_EVICTION_COUNT_DESC =
     "Count of the number of blocks evicted from the block cache."

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

@@ -289,6 +289,11 @@ public interface MetricsRegionServerWrapper {
    */
   long getBlockCachePrimaryHitCount();
 
+  /**
+   * Get the count of hits to the block cache, for cacheable requests only.
+   */
+  long getBlockCacheHitCachingCount();
+
   /**
    * Get the count of misses to the block cache.
    */
@@ -299,6 +304,11 @@ public interface MetricsRegionServerWrapper {
    */
   long getBlockCachePrimaryMissCount();
 
+  /**
+   * Get the count of misses to the block cache, for cacheable requests only.
+   */
+  long getBlockCacheMissCachingCount();
+
   /**
    * Get the number of items evicted from the block cache.
    */

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

@@ -370,11 +370,16 @@ public class MetricsRegionServerSourceImpl extends BaseSourceImpl
           rsWrap.getBlockCacheHitCount())
         .addCounter(Interns.info(BLOCK_CACHE_PRIMARY_HIT_COUNT, BLOCK_CACHE_PRIMARY_HIT_COUNT_DESC),
           rsWrap.getBlockCachePrimaryHitCount())
+        .addCounter(Interns.info(BLOCK_CACHE_HIT_CACHING_COUNT, BLOCK_CACHE_HIT_CACHING_COUNT_DESC),
+          rsWrap.getBlockCacheHitCachingCount())
         .addCounter(Interns.info(BLOCK_CACHE_MISS_COUNT, BLOCK_COUNT_MISS_COUNT_DESC),
           rsWrap.getBlockCacheMissCount())
         .addCounter(
           Interns.info(BLOCK_CACHE_PRIMARY_MISS_COUNT, BLOCK_COUNT_PRIMARY_MISS_COUNT_DESC),
           rsWrap.getBlockCachePrimaryMissCount())
+        .addCounter(
+          Interns.info(BLOCK_CACHE_MISS_CACHING_COUNT, BLOCK_COUNT_MISS_CACHING_COUNT_DESC),
+          rsWrap.getBlockCacheMissCachingCount())
         .addCounter(Interns.info(BLOCK_CACHE_EVICTION_COUNT, BLOCK_CACHE_EVICTION_COUNT_DESC),
           rsWrap.getBlockCacheEvictedCount())
         .addCounter(

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerWrapperImpl.java

@@ -328,6 +328,11 @@ class MetricsRegionServerWrapperImpl implements MetricsRegionServerWrapper {
     return this.cacheStats != null ? this.cacheStats.getPrimaryHitCount() : 0L;
   }
 
+  @Override
+  public long getBlockCacheHitCachingCount() {
+    return this.cacheStats != null ? this.cacheStats.getHitCachingCount() : 0L;
+  }
+
   @Override
   public long getBlockCacheMissCount() {
     return this.cacheStats != null ? this.cacheStats.getMissCount() : 0L;
@@ -338,6 +343,11 @@ class MetricsRegionServerWrapperImpl implements MetricsRegionServerWrapper {
     return this.cacheStats != null ? this.cacheStats.getPrimaryMissCount() : 0L;
   }
 
+  @Override
+  public long getBlockCacheMissCachingCount() {
+    return this.cacheStats != null ? this.cacheStats.getMissCachingCount() : 0L;
+  }
+
   @Override
   public long getBlockCacheEvictedCount() {
     return this.cacheStats != null ? this.cacheStats.getEvictedCount() : 0L;

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

@@ -322,6 +322,11 @@ public class MetricsRegionServerWrapperStub implements MetricsRegionServerWrappe
     return 422;
   }
 
+  @Override
+  public long getBlockCacheHitCachingCount() {
+    return 16;
+  }
+
   @Override
   public long getBlockCacheMissCount() {
     return 417;
@@ -332,6 +337,11 @@ public class MetricsRegionServerWrapperStub implements MetricsRegionServerWrappe
     return 421;
   }
 
+  @Override
+  public long getBlockCacheMissCachingCount() {
+    return 17;
+  }
+
   @Override
   public long getBlockCacheEvictedCount() {
     return 418;

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

@@ -111,7 +111,9 @@ public class TestMetricsRegionServer {
     HELPER.assertGauge("blockCacheDataBlockCount", 300, serverSource);
     HELPER.assertGauge("blockCacheSize", 415, serverSource);
     HELPER.assertCounter("blockCacheHitCount", 416, serverSource);
+    HELPER.assertCounter("blockCacheHitCachingCount", 16, serverSource);
     HELPER.assertCounter("blockCacheMissCount", 417, serverSource);
+    HELPER.assertCounter("blockCacheMissCachingCount", 17, serverSource);
     HELPER.assertCounter("blockCacheEvictionCount", 418, serverSource);
     HELPER.assertGauge("blockCacheCountHitPercent", 98, serverSource);
     HELPER.assertGauge("blockCacheExpressHitPercent", 97, serverSource);