HBASE-29667 Correct block priority to SINGLE on the first write to the bucket cache (#7399)

Reviewed by: Kota-SH <[email protected]>
Signed-off-by: Wellington Chevreuil <[email protected]>

Author: Huginn-kio

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/bucket/BucketEntry.java

@@ -117,7 +117,7 @@ public class BucketEntry implements HBaseReferenceCounted {
     this.onDiskSizeWithHeader = onDiskSizeWithHeader;
     this.accessCounter = accessCounter;
     this.cachedTime = cachedTime;
-    this.priority = inMemory ? BlockPriority.MEMORY : BlockPriority.MULTI;
+    this.priority = inMemory ? BlockPriority.MEMORY : BlockPriority.SINGLE;
     this.refCnt = RefCnt.create(createRecycler.apply(this));
     this.markedAsEvicted = new AtomicBoolean(false);
     this.allocator = allocator;

hbase-server/src/test/java/org/apache/hadoop/hbase/io/hfile/bucket/TestBucketCache.java

@@ -60,6 +60,7 @@
 import org.apache.hadoop.hbase.Waiter;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
 import org.apache.hadoop.hbase.io.hfile.BlockCacheKey;
+import org.apache.hadoop.hbase.io.hfile.BlockPriority;
 import org.apache.hadoop.hbase.io.hfile.BlockType;
 import org.apache.hadoop.hbase.io.hfile.CacheTestUtils;
 import org.apache.hadoop.hbase.io.hfile.CacheTestUtils.HFileBlockPair;
@@ -1115,4 +1116,13 @@ private BucketCache testEvictOrphans(long orphanEvictionGracePeriod) throws Exce
     bucketCache.freeSpace("test");
     return bucketCache;
   }
+
+  @Test
+  public void testBlockPriority() throws Exception {
+    HFileBlockPair block = CacheTestUtils.generateHFileBlocks(BLOCK_SIZE, 1)[0];
+    cacheAndWaitUntilFlushedToBucket(cache, block.getBlockName(), block.getBlock(), true);
+    assertEquals(cache.backingMap.get(block.getBlockName()).getPriority(), BlockPriority.SINGLE);
+    cache.getBlock(block.getBlockName(), true, false, true);
+    assertEquals(cache.backingMap.get(block.getBlockName()).getPriority(), BlockPriority.MULTI);
+  }
 }