Package org.rocksdb

Class HashSkipListMemTableConfig

  • public class HashSkipListMemTableConfig
extends MemTableConfig
    The config for hash skip-list mem-table representation. Such mem-table representation contains a fix-sized array of buckets, where each bucket points to a skiplist (or null if the bucket is empty). Note that since this mem-table representation relies on the key prefix, it is required to invoke one of the usePrefixExtractor functions to specify how to extract key prefix given a key. If proper prefix-extractor is not set, then RocksDB will use the default memtable representation (SkipList) instead and post a warning in the LOG.

    • Constructor Detail

      • HashSkipListMemTableConfig

        public HashSkipListMemTableConfig()
        HashSkipListMemTableConfig constructor

    • Method Detail

      • setBucketCount

        public HashSkipListMemTableConfig setBucketCount​(long count)
        Set the number of hash buckets used in the hash skiplist memtable. Default = 1000000.
        Parameters:
        count - the number of hash buckets used in the hash skiplist memtable.
        Returns:
        the reference to the current HashSkipListMemTableConfig.

      • bucketCount

        public long bucketCount()
        Returns:
        the number of hash buckets

      • setHeight

        public HashSkipListMemTableConfig setHeight​(int height)
        Set the height of the skip list. Default = 4.
        Parameters:
        height - height to set.
        Returns:
        the reference to the current HashSkipListMemTableConfig.

      • height

        public int height()
        Returns:
        the height of the skip list.

      • setBranchingFactor

        public HashSkipListMemTableConfig setBranchingFactor​(int bf)
        Set the branching factor used in the hash skip-list memtable. This factor controls the probabilistic size ratio between adjacent links in the skip list.
        Parameters:
        bf - the probabilistic size ratio between adjacent link lists in the skip list.
        Returns:
        the reference to the current HashSkipListMemTableConfig.

      • branchingFactor

        public int branchingFactor()
        Returns:
        branching factor, the probabilistic size ratio between adjacent links in the skip list.

      • newMemTableFactoryHandle

        protected long newMemTableFactoryHandle()
        Description copied from class: MemTableConfig
        This function should only be called by Options.setMemTableConfig(), which will create a c++ shared-pointer to the c++ MemTableRepFactory that associated with the Java MemTableConfig.
        Specified by:
        newMemTableFactoryHandle in class MemTableConfig
        Returns:
        native handle address to native memory table instance.
        See Also:
        Options.setMemTableConfig(MemTableConfig)