Merge pull request #249 from tdfischer/decompression-refactoring

Decompression refactoring

table/block.cc

@@ -299,10 +299,7 @@ uint32_t Block::NumRestarts() const {
 
 Block::Block(const BlockContents& contents)
     : data_(contents.data.data()),
-      size_(contents.data.size()),
-      owned_(contents.heap_allocated),
-      cachable_(contents.cachable),
-      compression_type_(contents.compression_type) {
+      size_(contents.data.size()) {
   if (size_ < sizeof(uint32_t)) {
     size_ = 0;  // Error marker
   } else {
@@ -315,10 +312,8 @@ Block::Block(const BlockContents& contents)
   }
 }
 
-Block::~Block() {
-  if (owned_) {
-    delete[] data_;
-  }
+Block::Block(BlockContents&& contents) : Block(contents) {
+  contents_ = std::move(contents);
 }
 
 Iterator* Block::NewIterator(

table/block.h

@@ -14,6 +14,10 @@
 #include "rocksdb/iterator.h"
 #include "rocksdb/options.h"
 #include "db/dbformat.h"
+#include "table/block_prefix_index.h"
+#include "table/block_hash_index.h"
+
+#include "format.h"
 
 namespace rocksdb {
 
@@ -26,15 +30,16 @@ class BlockPrefixIndex;
 class Block {
  public:
   // Initialize the block with the specified contents.
+  explicit Block(BlockContents&& contents);
   explicit Block(const BlockContents& contents);
 
-  ~Block();
+  ~Block() = default;
 
   size_t size() const { return size_; }
   const char* data() const { return data_; }
-  bool cachable() const { return cachable_; }
+  bool cachable() const { return contents_.cachable; }
   uint32_t NumRestarts() const;
-  CompressionType compression_type() const { return compression_type_; }
+  CompressionType compression_type() const { return contents_.compression_type; }
 
   // If hash index lookup is enabled and `use_hash_index` is true. This block
   // will do hash lookup for the key prefix.
@@ -58,12 +63,10 @@ class Block {
   size_t ApproximateMemoryUsage() const;
 
  private:
+  BlockContents contents_;
   const char* data_;
   size_t size_;
   uint32_t restart_offset_;     // Offset in data_ of restart array
-  bool owned_;                  // Block owns data_[]
-  bool cachable_;
-  CompressionType compression_type_;
   std::unique_ptr<BlockHashIndex> hash_index_;
   std::unique_ptr<BlockPrefixIndex> prefix_index_;
 

table/block_based_filter_block.cc

@@ -138,7 +138,7 @@ void BlockBasedFilterBlockBuilder::GenerateFilter() {
 BlockBasedFilterBlockReader::BlockBasedFilterBlockReader(
     const SliceTransform* prefix_extractor,
     const BlockBasedTableOptions& table_opt,
-    const Slice& contents, bool delete_contents_after_use)
+    const Slice& contents)
     : policy_(table_opt.filter_policy.get()),
       prefix_extractor_(prefix_extractor),
       whole_key_filtering_(table_opt.whole_key_filtering),
@@ -155,9 +155,14 @@ BlockBasedFilterBlockReader::BlockBasedFilterBlockReader(
   data_ = contents.data();
   offset_ = data_ + last_word;
   num_ = (n - 5 - last_word) / 4;
-  if (delete_contents_after_use) {
-    filter_data.reset(contents.data());
-  }
+}
+
+BlockBasedFilterBlockReader::BlockBasedFilterBlockReader(
+    const SliceTransform* prefix_extractor,
+    const BlockBasedTableOptions& table_opt,
+    BlockContents &&contents)
+    : BlockBasedFilterBlockReader (prefix_extractor, table_opt, contents.data) {
+  contents_ = std::move(contents);
 }
 
 bool BlockBasedFilterBlockReader::KeyMayMatch(const Slice& key,

table/block_based_filter_block.h

@@ -74,8 +74,10 @@ class BlockBasedFilterBlockReader : public FilterBlockReader {
   // REQUIRES: "contents" and *policy must stay live while *this is live.
   BlockBasedFilterBlockReader(const SliceTransform* prefix_extractor,
                               const BlockBasedTableOptions& table_opt,
-                              const Slice& contents,
-                              bool delete_contents_after_use = false);
+                              const Slice& contents);
+  BlockBasedFilterBlockReader(const SliceTransform* prefix_extractor,
+                              const BlockBasedTableOptions& table_opt,
+                              BlockContents&& contents);
   virtual bool IsBlockBased() override { return true; }
   virtual bool KeyMayMatch(const Slice& key,
                            uint64_t block_offset = kNotValid) override;
@@ -91,7 +93,7 @@ class BlockBasedFilterBlockReader : public FilterBlockReader {
   const char* offset_;  // Pointer to beginning of offset array (at block-end)
   size_t num_;          // Number of entries in offset array
   size_t base_lg_;      // Encoding parameter (see kFilterBaseLg in .cc file)
-  std::unique_ptr<const char[]> filter_data;
+  BlockContents contents_;
 
   bool MayMatch(const Slice& entry, uint64_t block_offset);
 

table/block_based_table_builder.cc

@@ -17,6 +17,7 @@
 #include <memory>
 #include <string>
 #include <unordered_map>
+#include <utility>
 
 #include "db/dbformat.h"
 
@@ -634,18 +635,13 @@ Status BlockBasedTableBuilder::InsertBlockInCache(const Slice& block_contents,
     Cache::Handle* cache_handle = nullptr;
     size_t size = block_contents.size();
 
-    char* ubuf = new char[size + 1];  // make a new copy
-    memcpy(ubuf, block_contents.data(), size);
+    std::unique_ptr<char[]> ubuf(new char[size+1]);
+    memcpy(ubuf.get(), block_contents.data(), size);
     ubuf[size] = type;
 
-    BlockContents results;
-    Slice sl(ubuf, size);
-    results.data = sl;
-    results.cachable = true; // XXX
-    results.heap_allocated = true;
-    results.compression_type = type;
+    BlockContents results(std::move(ubuf), size, true, type);
 
-    Block* block = new Block(results);
+    Block* block = new Block(std::move(results));
 
     // make cache key by appending the file offset to the cache prefix id
     char* end = EncodeVarint64(

table/block_based_table_reader.cc

@@ -66,7 +66,7 @@ Status ReadBlockFromFile(RandomAccessFile* file, const Footer& footer,
   Status s = ReadBlockContents(file, footer, options, handle, &contents, env,
                                do_uncompress);
   if (s.ok()) {
-    *result = new Block(contents);
+    *result = new Block(std::move(contents));
   }
 
   return s;
@@ -252,9 +252,6 @@ class HashIndexReader : public IndexReader {
                           &prefixes_meta_contents, env,
                           true /* do decompression */);
     if (!s.ok()) {
-      if (prefixes_contents.heap_allocated) {
-        delete[] prefixes_contents.data.data();
-      }
       // TODO: log error
       return Status::OK();
     }
@@ -269,7 +266,7 @@ class HashIndexReader : public IndexReader {
       // TODO: log error
       if (s.ok()) {
         new_index_reader->index_block_->SetBlockHashIndex(hash_index);
-        new_index_reader->OwnPrefixesContents(prefixes_contents);
+        new_index_reader->OwnPrefixesContents(std::move(prefixes_contents));
       }
     } else {
       BlockPrefixIndex* prefix_index = nullptr;
@@ -283,18 +280,6 @@ class HashIndexReader : public IndexReader {
       }
     }
 
-    // Always release prefix meta block
-    if (prefixes_meta_contents.heap_allocated) {
-      delete[] prefixes_meta_contents.data.data();
-    }
-
-    // Release prefix content block if we don't own it.
-    if (!new_index_reader->own_prefixes_contents_) {
-      if (prefixes_contents.heap_allocated) {
-        delete[] prefixes_contents.data.data();
-      }
-    }
-
     return Status::OK();
   }
 
@@ -314,24 +299,18 @@ class HashIndexReader : public IndexReader {
  private:
   HashIndexReader(const Comparator* comparator, Block* index_block)
       : IndexReader(comparator),
-        index_block_(index_block),
-        own_prefixes_contents_(false) {
+        index_block_(index_block) {
     assert(index_block_ != nullptr);
   }
 
   ~HashIndexReader() {
-    if (own_prefixes_contents_ && prefixes_contents_.heap_allocated) {
-      delete[] prefixes_contents_.data.data();
-    }
   }
 
-  void OwnPrefixesContents(const BlockContents& prefixes_contents) {
-    prefixes_contents_ = prefixes_contents;
-    own_prefixes_contents_ = true;
+  void OwnPrefixesContents(BlockContents&& prefixes_contents) {
+    prefixes_contents_ = std::move(prefixes_contents);
   }
 
   std::unique_ptr<Block> index_block_;
-  bool own_prefixes_contents_;
   BlockContents prefixes_contents_;
 };
 
@@ -677,7 +656,7 @@ Status BlockBasedTable::GetDataBlockFromCache(
 
   // Insert uncompressed block into block cache
   if (s.ok()) {
-    block->value = new Block(contents);  // uncompressed block
+    block->value = new Block(std::move(contents));  // uncompressed block
     assert(block->value->compression_type() == kNoCompression);
     if (block_cache != nullptr && block->value->cachable() &&
         read_options.fill_cache) {
@@ -715,7 +694,7 @@ Status BlockBasedTable::PutDataBlockToCache(
   }
 
   if (raw_block->compression_type() != kNoCompression) {
-    block->value = new Block(contents);  // uncompressed block
+    block->value = new Block(std::move(contents));  // uncompressed block
   } else {
     block->value = raw_block;
     raw_block = nullptr;
@@ -768,15 +747,14 @@ FilterBlockReader* BlockBasedTable::ReadFilter(
   assert(rep->filter_policy);
   if (kFilterBlockPrefix == filter_block_prefix) {
     return new BlockBasedFilterBlockReader(rep->ioptions.prefix_extractor,
-        rep->table_options, block.data, block.heap_allocated);
+        rep->table_options, std::move(block));
   } else if (kFullFilterBlockPrefix == filter_block_prefix) {
     auto filter_bits_reader = rep->filter_policy->
         GetFilterBitsReader(block.data);
 
     if (filter_bits_reader != nullptr) {
       return new FullFilterBlockReader(rep->ioptions.prefix_extractor,
-          rep->table_options, block.data, filter_bits_reader,
-          block.heap_allocated);
+          rep->table_options, std::move(block), filter_bits_reader);
     }
   }
   return nullptr;

table/block_test.cc

@@ -92,8 +92,7 @@ TEST(BlockTest, SimpleTest) {
   BlockContents contents;
   contents.data = rawblock;
   contents.cachable = false;
-  contents.heap_allocated = false;
-  Block reader(contents);
+  Block reader(std::move(contents));
 
   // read contents of block sequentially
   int count = 0;
@@ -143,12 +142,11 @@ BlockContents GetBlockContents(std::unique_ptr<BlockBuilder> *builder,
   BlockContents contents;
   contents.data = rawblock;
   contents.cachable = false;
-  contents.heap_allocated = false;
 
   return contents;
 }
 
-void CheckBlockContents(BlockContents contents, const int max_key,
+void CheckBlockContents(const BlockContents &contents, const int max_key,
                         const std::vector<std::string> &keys,
                         const std::vector<std::string> &values) {
   const size_t prefix_size = 6;

table/filter_block.h

@@ -18,17 +18,22 @@
 
 #pragma once
 
+#include <memory>
 #include <stddef.h>
 #include <stdint.h>
 #include <string>
 #include <vector>
 #include "rocksdb/options.h"
 #include "rocksdb/slice.h"
+#include "rocksdb/slice_transform.h"
 #include "rocksdb/table.h"
+#include "util/hash.h"
+#include "format.h"
 
 namespace rocksdb {
 
 const uint64_t kNotValid = ULLONG_MAX;
+class FilterPolicy;
 
 // A FilterBlockBuilder is used to construct all of the filters for a
 // particular Table.  It generates a single string which is stored as

table/format.cc

@@ -255,112 +255,53 @@ Status ReadBlock(RandomAccessFile* file, const Footer& footer,
   return s;
 }
 
-// Decompress a block according to params
-// May need to malloc a space for cache usage
-Status DecompressBlock(BlockContents* result, size_t block_size,
-                          bool do_uncompress, const char* buf,
-                          const Slice& contents, bool use_stack_buf) {
-  Status s;
-  size_t n = block_size;
-  const char* data = contents.data();
-
-  result->data = Slice();
-  result->cachable = false;
-  result->heap_allocated = false;
-
-  PERF_TIMER_GUARD(block_decompress_time);
-  rocksdb::CompressionType compression_type =
-      static_cast<rocksdb::CompressionType>(data[n]);
-  // If the caller has requested that the block not be uncompressed
-  if (!do_uncompress || compression_type == kNoCompression) {
-    if (data != buf) {
-      // File implementation gave us pointer to some other data.
-      // Use it directly under the assumption that it will be live
-      // while the file is open.
-      result->data = Slice(data, n);
-      result->heap_allocated = false;
-      result->cachable = false;  // Do not double-cache
-    } else {
-      if (use_stack_buf) {
-        // Need to allocate space in heap for cache usage
-        char* new_buf = new char[n];
-        memcpy(new_buf, buf, n);
-        result->data = Slice(new_buf, n);
-      } else {
-        result->data = Slice(buf, n);
-      }
-
-      result->heap_allocated = true;
-      result->cachable = true;
-    }
-    result->compression_type = compression_type;
-    s = Status::OK();
+Status ReadBlockContents(RandomAccessFile* file, const Footer& footer,
+                         const ReadOptions& options, const BlockHandle& handle,
+                         BlockContents *contents, Env* env,
+                         bool decompression_requested) {
+  Status status;
+  Slice slice;
+  size_t n = static_cast<size_t>(handle.size());
+  std::unique_ptr<char[]> heap_buf;
+  char stack_buf[DefaultStackBufferSize];
+  char *used_buf = nullptr;
+  rocksdb::CompressionType compression_type;
+
+  if (decompression_requested && n + kBlockTrailerSize < DefaultStackBufferSize) {
+    //If we've got a small enough hunk of data, read it in to the
+    //trivially allocated stack buffer instead of needing a full malloc()
+    used_buf = &stack_buf[0];
   } else {
-    s = UncompressBlockContents(data, n, result);
+    heap_buf = std::unique_ptr<char[]>(new char[n + kBlockTrailerSize]);
+    used_buf = heap_buf.get();
   }
-  return s;
-}
 
-// Read and Decompress block
-// Use buf in stack as temp reading buffer
-Status ReadAndDecompressFast(RandomAccessFile* file, const Footer& footer,
-                             const ReadOptions& options,
-                             const BlockHandle& handle, BlockContents* result,
-                             Env* env, bool do_uncompress) {
-  Status s;
-  Slice contents;
-  size_t n = static_cast<size_t>(handle.size());
-  char buf[DefaultStackBufferSize];
+  status = ReadBlock(file, footer, options, handle, &slice, used_buf);
 
-  s = ReadBlock(file, footer, options, handle, &contents, buf);
-  if (!s.ok()) {
-    return s;
-  }
-  s = DecompressBlock(result, n, do_uncompress, buf, contents, true);
-  if (!s.ok()) {
-    return s;
+  if (!status.ok()) {
+    return status;
   }
-  return s;
-}
 
-// Read and Decompress block
-// Use buf in heap as temp reading buffer
-Status ReadAndDecompress(RandomAccessFile* file, const Footer& footer,
-                         const ReadOptions& options, const BlockHandle& handle,
-                         BlockContents* result, Env* env, bool do_uncompress) {
-  Status s;
-  Slice contents;
-  size_t n = static_cast<size_t>(handle.size());
-  char* buf = new char[n + kBlockTrailerSize];
+  PERF_TIMER_GUARD(block_decompress_time);
 
-  s = ReadBlock(file, footer, options, handle, &contents, buf);
-  if (!s.ok()) {
-    delete[] buf;
-    return s;
-  }
-  s = DecompressBlock(result, n, do_uncompress, buf, contents, false);
-  if (!s.ok()) {
-    delete[] buf;
-    return s;
+  compression_type = static_cast<rocksdb::CompressionType>(slice.data()[n]);
+
+  if (decompression_requested && compression_type != kNoCompression) {
+    return UncompressBlockContents(slice.data(), n, contents);
   }
 
-  if (result->data.data() != buf) {
-    delete[] buf;
+  if (slice.data() != used_buf) {
+    *contents = BlockContents(Slice(slice.data(), n), false, compression_type);
+    return status;
   }
-  return s;
-}
 
-Status ReadBlockContents(RandomAccessFile* file, const Footer& footer,
-                         const ReadOptions& options, const BlockHandle& handle,
-                         BlockContents* result, Env* env, bool do_uncompress) {
-  size_t n = static_cast<size_t>(handle.size());
-  if (do_uncompress && n + kBlockTrailerSize < DefaultStackBufferSize) {
-    return ReadAndDecompressFast(file, footer, options, handle, result, env,
-                                 do_uncompress);
-  } else {
-    return ReadAndDecompress(file, footer, options, handle, result, env,
-                             do_uncompress);
+  if (used_buf == &stack_buf[0]) {
+    heap_buf = std::unique_ptr<char[]>(new char[n]);
+    memcpy(heap_buf.get(), stack_buf, n);
   }
+
+  *contents = BlockContents(std::move(heap_buf), n, true, compression_type);
+  return status;
 }
 
 //
@@ -370,8 +311,8 @@ Status ReadBlockContents(RandomAccessFile* file, const Footer& footer,
 // buffer is returned via 'result' and it is upto the caller to
 // free this buffer.
 Status UncompressBlockContents(const char* data, size_t n,
-                               BlockContents* result) {
-  char* ubuf = nullptr;
+                               BlockContents* contents) {
+  std::unique_ptr<char[]> ubuf;
   int decompress_size = 0;
   assert(data[n] != kNoCompression);
   switch (data[n]) {
@@ -382,64 +323,52 @@ Status UncompressBlockContents(const char* data, size_t n,
       if (!port::Snappy_GetUncompressedLength(data, n, &ulength)) {
         return Status::Corruption(snappy_corrupt_msg);
       }
-      ubuf = new char[ulength];
-      if (!port::Snappy_Uncompress(data, n, ubuf)) {
-        delete[] ubuf;
+      ubuf = std::unique_ptr<char[]>(new char[ulength]);
+      if (!port::Snappy_Uncompress(data, n, ubuf.get())) {
         return Status::Corruption(snappy_corrupt_msg);
       }
-      result->data = Slice(ubuf, ulength);
-      result->heap_allocated = true;
-      result->cachable = true;
+      *contents = BlockContents(std::move(ubuf), ulength, true, kNoCompression);
       break;
     }
     case kZlibCompression:
-      ubuf = port::Zlib_Uncompress(data, n, &decompress_size);
+      ubuf = std::unique_ptr<char[]>(port::Zlib_Uncompress(data, n, &decompress_size));
       static char zlib_corrupt_msg[] =
         "Zlib not supported or corrupted Zlib compressed block contents";
       if (!ubuf) {
         return Status::Corruption(zlib_corrupt_msg);
       }
-      result->data = Slice(ubuf, decompress_size);
-      result->heap_allocated = true;
-      result->cachable = true;
+      *contents = BlockContents(std::move(ubuf), decompress_size, true, kNoCompression);
       break;
     case kBZip2Compression:
-      ubuf = port::BZip2_Uncompress(data, n, &decompress_size);
+      ubuf = std::unique_ptr<char[]>(port::BZip2_Uncompress(data, n, &decompress_size));
       static char bzip2_corrupt_msg[] =
         "Bzip2 not supported or corrupted Bzip2 compressed block contents";
       if (!ubuf) {
         return Status::Corruption(bzip2_corrupt_msg);
       }
-      result->data = Slice(ubuf, decompress_size);
-      result->heap_allocated = true;
-      result->cachable = true;
+      *contents = BlockContents(std::move(ubuf), decompress_size, true, kNoCompression);
       break;
     case kLZ4Compression:
-      ubuf = port::LZ4_Uncompress(data, n, &decompress_size);
+      ubuf = std::unique_ptr<char[]>(port::LZ4_Uncompress(data, n, &decompress_size));
       static char lz4_corrupt_msg[] =
           "LZ4 not supported or corrupted LZ4 compressed block contents";
       if (!ubuf) {
         return Status::Corruption(lz4_corrupt_msg);
       }
-      result->data = Slice(ubuf, decompress_size);
-      result->heap_allocated = true;
-      result->cachable = true;
+      *contents = BlockContents(std::move(ubuf), decompress_size, true, kNoCompression);
       break;
     case kLZ4HCCompression:
-      ubuf = port::LZ4_Uncompress(data, n, &decompress_size);
+      ubuf = std::unique_ptr<char[]>(port::LZ4_Uncompress(data, n, &decompress_size));
       static char lz4hc_corrupt_msg[] =
           "LZ4HC not supported or corrupted LZ4HC compressed block contents";
       if (!ubuf) {
         return Status::Corruption(lz4hc_corrupt_msg);
       }
-      result->data = Slice(ubuf, decompress_size);
-      result->heap_allocated = true;
-      result->cachable = true;
+      *contents = BlockContents(std::move(ubuf), decompress_size, true, kNoCompression);
       break;
     default:
       return Status::Corruption("bad block type");
   }
-  result->compression_type = kNoCompression;  // not compressed any more
   return Status::OK();
 }
 

table/format.h

@@ -160,28 +160,39 @@ static const size_t kBlockTrailerSize = 5;
 struct BlockContents {
   Slice data;           // Actual contents of data
   bool cachable;        // True iff data can be cached
-  bool heap_allocated;  // True iff caller should delete[] data.data()
   CompressionType compression_type;
+  std::unique_ptr<char[]> allocation;
+
+  BlockContents()
+   : cachable(false),
+     compression_type(kNoCompression) {}
+
+  BlockContents(const Slice &_data, bool _cachable, CompressionType _compression_type)
+    : data(_data),
+      cachable(_cachable),
+      compression_type(_compression_type) {}
+
+  BlockContents(std::unique_ptr<char[]> &&_data, size_t _size, bool _cachable, CompressionType _compression_type)
+    : data(_data.get(), _size),
+      cachable(_cachable),
+      compression_type(_compression_type),
+      allocation(std::move(_data)) {}
 };
 
 // Read the block identified by "handle" from "file".  On failure
 // return non-OK.  On success fill *result and return OK.
-extern Status ReadBlockContents(RandomAccessFile* file,
-                                const Footer& footer,
+extern Status ReadBlockContents(RandomAccessFile* file, const Footer& footer,
                                 const ReadOptions& options,
-                                const BlockHandle& handle,
-                                BlockContents* result,
-                                Env* env,
-                                bool do_uncompress);
+                                const BlockHandle& handle, BlockContents* contents,
+                                Env* env, bool do_uncompress);
 
 // The 'data' points to the raw block contents read in from file.
 // This method allocates a new heap buffer and the raw block
 // contents are uncompresed into this buffer. This buffer is
 // returned via 'result' and it is upto the caller to
 // free this buffer.
-extern Status UncompressBlockContents(const char* data,
-                                      size_t n,
-                                      BlockContents* result);
+extern Status UncompressBlockContents(const char* data, size_t n,
+                                      BlockContents* contents);
 
 // Implementation details follow.  Clients should ignore,
 

table/full_filter_block.cc

@@ -56,16 +56,21 @@ FullFilterBlockReader::FullFilterBlockReader(
     const SliceTransform* prefix_extractor,
     const BlockBasedTableOptions& table_opt,
     const Slice& contents,
-    FilterBitsReader* filter_bits_reader, bool delete_contents_after_use)
+    FilterBitsReader* filter_bits_reader)
     : prefix_extractor_(prefix_extractor),
       whole_key_filtering_(table_opt.whole_key_filtering),
       contents_(contents) {
   assert(filter_bits_reader != nullptr);
   filter_bits_reader_.reset(filter_bits_reader);
+}
 
-  if (delete_contents_after_use) {
-    filter_data_.reset(contents.data());
-  }
+FullFilterBlockReader::FullFilterBlockReader(
+    const SliceTransform* prefix_extractor,
+    const BlockBasedTableOptions& table_opt,
+    BlockContents&& contents,
+    FilterBitsReader* filter_bits_reader)
+    : FullFilterBlockReader(prefix_extractor, table_opt, contents.data, filter_bits_reader) {
+  block_contents_ = std::move(contents);
 }
 
 bool FullFilterBlockReader::KeyMayMatch(const Slice& key,

table/full_filter_block.h

@@ -75,8 +75,11 @@ class FullFilterBlockReader : public FilterBlockReader {
   explicit FullFilterBlockReader(const SliceTransform* prefix_extractor,
                                  const BlockBasedTableOptions& table_opt,
                                  const Slice& contents,
-                                 FilterBitsReader* filter_bits_reader,
-                                 bool delete_contents_after_use = false);
+                                 FilterBitsReader* filter_bits_reader);
+  explicit FullFilterBlockReader(const SliceTransform* prefix_extractor,
+                                 const BlockBasedTableOptions& table_opt,
+                                 BlockContents&& contents,
+                                 FilterBitsReader* filter_bits_reader);
 
   // bits_reader is created in filter_policy, it should be passed in here
   // directly. and be deleted here
@@ -95,6 +98,7 @@ class FullFilterBlockReader : public FilterBlockReader {
 
   std::unique_ptr<FilterBitsReader> filter_bits_reader_;
   Slice contents_;
+  BlockContents block_contents_;
   std::unique_ptr<const char[]> filter_data_;
 
   bool MayMatch(const Slice& entry);

table/meta_blocks.cc

@@ -141,14 +141,15 @@ Status ReadProperties(const Slice &handle_value, RandomAccessFile *file,
   BlockContents block_contents;
   ReadOptions read_options;
   read_options.verify_checksums = false;
-  Status s = ReadBlockContents(file, footer, read_options, handle,
-                               &block_contents, env, false);
+  Status s;
+  s = ReadBlockContents(file, footer, read_options, handle, &block_contents,
+                        env, false);
 
   if (!s.ok()) {
     return s;
   }
 
-  Block properties_block(block_contents);
+  Block properties_block(std::move(block_contents));
   std::unique_ptr<Iterator> iter(
       properties_block.NewIterator(BytewiseComparator()));
 
@@ -228,12 +229,12 @@ Status ReadTableProperties(RandomAccessFile* file, uint64_t file_size,
   BlockContents metaindex_contents;
   ReadOptions read_options;
   read_options.verify_checksums = false;
-  s = ReadBlockContents(file, footer, read_options, metaindex_handle,
-                        &metaindex_contents, env, false);
+  s = ReadBlockContents(file, footer, read_options, metaindex_handle, &metaindex_contents,
+                        env, false);
   if (!s.ok()) {
     return s;
   }
-  Block metaindex_block(metaindex_contents);
+  Block metaindex_block(std::move(metaindex_contents));
   std::unique_ptr<Iterator> meta_iter(
       metaindex_block.NewIterator(BytewiseComparator()));
 
@@ -287,7 +288,7 @@ Status FindMetaBlock(RandomAccessFile* file, uint64_t file_size,
   if (!s.ok()) {
     return s;
   }
-  Block metaindex_block(metaindex_contents);
+  Block metaindex_block(std::move(metaindex_contents));
 
   std::unique_ptr<Iterator> meta_iter;
   meta_iter.reset(metaindex_block.NewIterator(BytewiseComparator()));
@@ -299,41 +300,36 @@ Status ReadMetaBlock(RandomAccessFile* file, uint64_t file_size,
                      uint64_t table_magic_number, Env* env,
                      const std::string& meta_block_name,
                      BlockContents* contents) {
+  Status status;
   Footer footer(table_magic_number);
-  auto s = ReadFooterFromFile(file, file_size, &footer);
-  if (!s.ok()) {
-    return s;
-  }
+  status = ReadFooterFromFile(file, file_size, &footer);
+  if (!status.ok()) return status;
 
   // Reading metaindex block
   auto metaindex_handle = footer.metaindex_handle();
   BlockContents metaindex_contents;
   ReadOptions read_options;
   read_options.verify_checksums = false;
-  s = ReadBlockContents(file, footer, read_options, metaindex_handle,
-                        &metaindex_contents, env, false);
-  if (!s.ok()) {
-    return s;
-  }
+  status = ReadBlockContents(file, footer, read_options, metaindex_handle,
+                             &metaindex_contents, env, false);
+  if (!status.ok()) return status;
 
   // Finding metablock
-  Block metaindex_block(metaindex_contents);
+  Block metaindex_block(std::move(metaindex_contents));
 
   std::unique_ptr<Iterator> meta_iter;
   meta_iter.reset(metaindex_block.NewIterator(BytewiseComparator()));
 
   BlockHandle block_handle;
-  s = FindMetaBlock(meta_iter.get(), meta_block_name, &block_handle);
+  status = FindMetaBlock(meta_iter.get(), meta_block_name, &block_handle);
 
-  if (!s.ok()) {
-    return s;
+  if (!status.ok()) {
+    return status;
   }
 
   // Reading metablock
-  s = ReadBlockContents(file, footer, read_options, block_handle, contents, env,
-                        false);
-
-  return s;
+  return ReadBlockContents(file, footer, read_options, block_handle, contents,
+                           env, false);
 }
 
 }  // namespace rocksdb

table/plain_table_reader.cc

@@ -20,6 +20,7 @@
 
 #include "table/block.h"
 #include "table/bloom_block.h"
+#include "table/filter_block.h"
 #include "table/format.h"
 #include "table/meta_blocks.h"
 #include "table/two_level_iterator.h"

table/table_test.cc

@@ -265,8 +265,7 @@ class BlockConstructor: public Constructor {
     BlockContents contents;
     contents.data = data_;
     contents.cachable = false;
-    contents.heap_allocated = false;
-    block_ = new Block(contents);
+    block_ = new Block(std::move(contents));
     return Status::OK();
   }
   virtual Iterator* NewIterator() const {