HBASE-22463 Some paths in HFileScannerImpl did not consider block#rel…

…ease which will exhaust the ByteBuffAllocator (#257)

hbase-external-blockcache/src/main/java/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.java

@@ -37,7 +37,6 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
-import org.apache.hadoop.hbase.io.hfile.Cacheable.MemoryType;
 import org.apache.hadoop.hbase.nio.ByteBuff;
 import org.apache.hadoop.hbase.nio.SingleByteBuff;
 import org.apache.hadoop.hbase.trace.TraceUtil;
@@ -272,8 +271,7 @@ public CachedData encode(HFileBlock block) {
     public HFileBlock decode(CachedData d) {
       try {
         ByteBuff buf = new SingleByteBuff(ByteBuffer.wrap(d.getData()));
-        return (HFileBlock) HFileBlock.BLOCK_DESERIALIZER.deserialize(buf, ByteBuffAllocator.HEAP,
-          MemoryType.EXCLUSIVE);
+        return (HFileBlock) HFileBlock.BLOCK_DESERIALIZER.deserialize(buf, ByteBuffAllocator.HEAP);
       } catch (IOException e) {
         LOG.warn("Failed to deserialize data from memcached", e);
       }

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

@@ -63,20 +63,6 @@ public interface Cacheable extends HeapSize, HBaseReferenceCounted {
    */
   BlockType getBlockType();
 
-  /**
-   * @return the {@code MemoryType} of this Cacheable
-   */
-  MemoryType getMemoryType();
-
-  /**
-   * SHARED means when this Cacheable is read back from cache it refers to the same memory area as
-   * used by the cache for caching it. EXCLUSIVE means when this Cacheable is read back from cache,
-   * the data was copied to an exclusive memory area of this Cacheable.
-   */
-  enum MemoryType {
-    SHARED, EXCLUSIVE
-  }
-
   /******************************* ReferenceCounted Interfaces ***********************************/
 
   /**

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

@@ -20,9 +20,8 @@
 import java.io.IOException;
 
 import org.apache.hadoop.hbase.io.ByteBuffAllocator;
-import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hadoop.hbase.io.hfile.Cacheable.MemoryType;
 import org.apache.hadoop.hbase.nio.ByteBuff;
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * Interface for a deserializer. Throws an IOException if the serialized data is incomplete or
@@ -33,11 +32,10 @@ public interface CacheableDeserializer<T extends Cacheable> {
   /**
    * @param b ByteBuff to deserialize the Cacheable.
    * @param allocator to manage NIO ByteBuffers for future allocation or de-allocation.
-   * @param memType the {@link MemoryType} of the buffer
    * @return T the deserialized object.
    * @throws IOException
    */
-  T deserialize(ByteBuff b, ByteBuffAllocator allocator, MemoryType memType) throws IOException;
+  T deserialize(ByteBuff b, ByteBuffAllocator allocator) throws IOException;
 
   /**
    * Get the identifier of this deserializer. Identifier is unique for each deserializer and

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

@@ -201,8 +201,6 @@ static class Header {
    */
   private long offset = UNSET;
 
-  private MemoryType memType = MemoryType.EXCLUSIVE;
-
   /**
    * The on-disk size of the next block, including the header and checksums if present.
    * UNSET if unknown.
@@ -274,7 +272,7 @@ private BlockDeserializer() {
     }
 
     @Override
-    public HFileBlock deserialize(ByteBuff buf, ByteBuffAllocator alloc, MemoryType memType)
+    public HFileBlock deserialize(ByteBuff buf, ByteBuffAllocator alloc)
         throws IOException {
       // The buf has the file block followed by block metadata.
       // Set limit to just before the BLOCK_METADATA_SPACE then rewind.
@@ -287,8 +285,7 @@ public HFileBlock deserialize(ByteBuff buf, ByteBuffAllocator alloc, MemoryType
       boolean usesChecksum = buf.get() == (byte) 1;
       long offset = buf.getLong();
       int nextBlockOnDiskSize = buf.getInt();
-      return new HFileBlock(newByteBuff, usesChecksum, memType, offset, nextBlockOnDiskSize, null,
-          alloc);
+      return new HFileBlock(newByteBuff, usesChecksum, offset, nextBlockOnDiskSize, null, alloc);
     }
 
     @Override
@@ -366,7 +363,7 @@ public HFileBlock(BlockType blockType, int onDiskSizeWithoutHeader,
    * to that point.
    * @param buf Has header, content, and trailing checksums if present.
    */
-  HFileBlock(ByteBuff buf, boolean usesHBaseChecksum, MemoryType memType, final long offset,
+  HFileBlock(ByteBuff buf, boolean usesHBaseChecksum, final long offset,
       final int nextBlockOnDiskSize, HFileContext fileContext, ByteBuffAllocator allocator)
       throws IOException {
     buf.rewind();
@@ -398,7 +395,6 @@ public HFileBlock(BlockType blockType, int onDiskSizeWithoutHeader,
     assert usesHBaseChecksum == fileContext.isUseHBaseChecksum();
     init(blockType, onDiskSizeWithoutHeader, uncompressedSizeWithoutHeader, prevBlockOffset, offset,
       onDiskDataSizeWithHeader, nextBlockOnDiskSize, fileContext, allocator);
-    this.memType = memType;
     this.offset = offset;
     this.buf = buf;
     this.buf.rewind();
@@ -1785,8 +1781,8 @@ protected HFileBlock readBlockDataInternal(FSDataInputStream is, long offset,
         // The onDiskBlock will become the headerAndDataBuffer for this block.
         // If nextBlockOnDiskSizeWithHeader is not zero, the onDiskBlock already
         // contains the header of next block, so no need to set next block's header in it.
-        HFileBlock hFileBlock = new HFileBlock(curBlock, checksumSupport, MemoryType.EXCLUSIVE,
-            offset, nextBlockOnDiskSize, fileContext, intoHeap ? HEAP: allocator);
+        HFileBlock hFileBlock = new HFileBlock(curBlock, checksumSupport, offset,
+            nextBlockOnDiskSize, fileContext, intoHeap ? HEAP : allocator);
         // Run check on uncompressed sizings.
         if (!fileContext.isCompressedOrEncrypted()) {
           hFileBlock.sanityCheckUncompressed();
@@ -2060,18 +2056,6 @@ HFileContext getHFileContext() {
     return this.fileContext;
   }
 
-  @Override
-  public MemoryType getMemoryType() {
-    return this.memType;
-  }
-
-  /**
-   * @return true if this block is backed by a shared memory area(such as that of a BucketCache).
-   */
-  boolean usesSharedMemory() {
-    return this.memType == MemoryType.SHARED;
-  }
-
   /**
    * Convert the contents of the block header into a human readable string.
    * This is mostly helpful for debugging. This assumes that the block