bf86af5174
Summary: Previous code is too convoluted and I must be drunk for letting such code to be written without a second thought. Thanks to the discussion with @sdong, I added the `Options` when generating the flusher, thus avoiding the tricks. Just FYI: I resisted to add Options in flush_block_policy.h since I wanted to avoid cyclic dependencies: FlushBlockPolicy dpends on Options and Options also depends FlushBlockPolicy... While I appreciate my effort to prevent it, the old design turns out creating more troubles than it tried to avoid. Test Plan: ran ./table_test Reviewers: sdong Reviewed By: sdong CC: sdong, leveldb Differential Revision: https://reviews.facebook.net/D16503
59 lines
1.7 KiB
C++
59 lines
1.7 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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#pragma once
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#include <string>
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namespace rocksdb {
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class Slice;
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class BlockBuilder;
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struct Options;
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// FlushBlockPolicy provides a configurable way to determine when to flush a
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// block in the block based tables,
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class FlushBlockPolicy {
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public:
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// Keep track of the key/value sequences and return the boolean value to
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// determine if table builder should flush current data block.
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virtual bool Update(const Slice& key,
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const Slice& value) = 0;
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virtual ~FlushBlockPolicy() { }
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};
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class FlushBlockPolicyFactory {
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public:
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// Return the name of the flush block policy.
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virtual const char* Name() const = 0;
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// Return a new block flush policy that flushes data blocks by data size.
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// FlushBlockPolicy may need to access the metadata of the data block
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// builder to determine when to flush the blocks.
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//
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// Callers must delete the result after any database that is using the
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// result has been closed.
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virtual FlushBlockPolicy* NewFlushBlockPolicy(
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const Options& options, const BlockBuilder& data_block_builder) const = 0;
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virtual ~FlushBlockPolicyFactory() { }
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};
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class FlushBlockBySizePolicyFactory : public FlushBlockPolicyFactory {
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public:
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FlushBlockBySizePolicyFactory() {}
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virtual const char* Name() const override {
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return "FlushBlockBySizePolicyFactory";
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}
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virtual FlushBlockPolicy* NewFlushBlockPolicy(
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const Options& options,
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const BlockBuilder& data_block_builder) const override;
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};
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} // rocksdb
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