85584d497e
In particular, we add a new FilterPolicy class. An instance of this class can be supplied in Options when opening a database. If supplied, the instance is used to generate summaries of keys (e.g., a bloom filter) which are placed in sstables. These summaries are consulted by DB::Get() so we can avoid reading sstable blocks that are guaranteed to not contain the key we are looking for. This change provides one implementation of FilterPolicy based on bloom filters. Other changes: - Updated version number to 1.4. - Some build tweaks. - C binding for CompactRange. - A few more benchmarks: deleteseq, deleterandom, readmissing, seekrandom. - Minor .gitignore update.
45 lines
1.0 KiB
C++
45 lines
1.0 KiB
C++
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#ifndef STORAGE_LEVELDB_TABLE_BLOCK_H_
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#define STORAGE_LEVELDB_TABLE_BLOCK_H_
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#include <stddef.h>
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#include <stdint.h>
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#include "leveldb/iterator.h"
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namespace leveldb {
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struct BlockContents;
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class Comparator;
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class Block {
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public:
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// Initialize the block with the specified contents.
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explicit Block(const BlockContents& contents);
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~Block();
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size_t size() const { return size_; }
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Iterator* NewIterator(const Comparator* comparator);
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private:
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uint32_t NumRestarts() const;
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const char* data_;
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size_t size_;
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uint32_t restart_offset_; // Offset in data_ of restart array
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bool owned_; // Block owns data_[]
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// No copying allowed
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Block(const Block&);
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void operator=(const Block&);
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class Iter;
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};
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} // namespace leveldb
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#endif // STORAGE_LEVELDB_TABLE_BLOCK_H_
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