YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.

//  This source code is licensed under the BSD-style license found in the

//  LICENSE file in the root directory of this source tree. An additional grant

//  of patent rights can be found in the PATENTS file in the same directory.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

#pragma once

#ifndef ROCKSDB_LITE

#include "yb/rocksdb/utilities/table_properties_collectors.h"

namespace rocksdb {

// A factory of a table property collector that marks a SST

// file as need-compaction when it observe at least "D" deletion

// entries in any "N" consecutive entires.

class CompactOnDeletionCollectorFactory

    : public TablePropertiesCollectorFactory {

 public:

  // A factory of a table property collector that marks a SST

  // file as need-compaction when it observe at least "D" deletion

  // entries in any "N" consecutive entires.

  //

  // @param sliding_window_size "N"

  // @param deletion_trigger "D"

  CompactOnDeletionCollectorFactory(

      size_t sliding_window_size,

      size_t deletion_trigger) :

          sliding_window_size_(sliding_window_size),

          deletion_trigger_(deletion_trigger) {}

  virtual ~CompactOnDeletionCollectorFactory() {}

  virtual TablePropertiesCollector* CreateTablePropertiesCollector(

      TablePropertiesCollectorFactory::Context context) override;

  virtual const char* Name() const override {

    return "CompactOnDeletionCollector";

  }

 private:

  size_t sliding_window_size_;

  size_t deletion_trigger_;

};

class CompactOnDeletionCollector : public TablePropertiesCollector {

 public:

  CompactOnDeletionCollector(

      size_t sliding_window_size,

      size_t deletion_trigger);

  // AddUserKey() will be called when a new key/value pair is inserted into the

  // table.

  // @params key    the user key that is inserted into the table.

  // @params value  the value that is inserted into the table.

  // @params file_size  file size up to now

  virtual Status AddUserKey(const Slice& key, const Slice& value,

                            EntryType type, SequenceNumber seq,

                            uint64_t file_size) override;

  // Finish() will be called when a table has already been built and is ready

  // for writing the properties block.

  // @params properties  User will add their collected statistics to

  // `properties`.

  virtual Status Finish(UserCollectedProperties* properties) override {

    Reset();

    return Status::OK();

  }

  // Return the human-readable properties, where the key is property name and

  // the value is the human-readable form of value.

  virtual UserCollectedProperties GetReadableProperties() const override {

    return UserCollectedProperties();

  }

  // The name of the properties collector can be used for debugging purpose.

  virtual const char* Name() const override {

    return "CompactOnDeletionCollector";

  }

  // EXPERIMENTAL Return whether the output file should be further compacted

  virtual bool NeedCompact() const override {

    return need_compaction_;

  }

  static const int kNumBuckets = 128;

 private:

  void Reset();

  // A ring buffer that used to count the number of deletion entries for every

  // "bucket_size_" keys.

  size_t num_deletions_in_buckets_[kNumBuckets];

  // the number of keys in a bucket

  size_t bucket_size_;

  size_t current_bucket_;

  size_t num_keys_in_current_bucket_;

  size_t num_deletions_in_observation_window_;

  size_t deletion_trigger_;

  // true if the current SST file needs to be compacted.

  bool need_compaction_;

};

}  // namespace rocksdb

#endif  // !ROCKSDB_LITE