Package org.rocksdb

Class LRUCache

  • All Implemented Interfaces:
    java.lang.AutoCloseable
    public class LRUCache
extends Cache
    Least Recently Used Cache

    • Constructor Detail

      • LRUCache

        public LRUCache​(long capacity)
        Create a new cache with a fixed size capacity
        Parameters:
        capacity - The fixed size capacity of the cache

      • LRUCache

        public LRUCache​(long capacity,
                int numShardBits)
        Create a new cache with a fixed size capacity. The cache is sharded to 2^numShardBits shards, by hash of the key. The total capacity is divided and evenly assigned to each shard. numShardBits = -1 means it is automatically determined: every shard will be at least 512KB and number of shard bits will not exceed 6.
        Parameters:
        capacity - The fixed size capacity of the cache
        numShardBits - The cache is sharded to 2^numShardBits shards, by hash of the key

      • LRUCache

        public LRUCache​(long capacity,
                int numShardBits,
                boolean strictCapacityLimit)
        Create a new cache with a fixed size capacity. The cache is sharded to 2^numShardBits shards, by hash of the key. The total capacity is divided and evenly assigned to each shard. If strictCapacityLimit is set, insert to the cache will fail when cache is full. numShardBits = -1 means it is automatically determined: every shard will be at least 512KB and number of shard bits will not exceed 6.
        Parameters:
        capacity - The fixed size capacity of the cache
        numShardBits - The cache is sharded to 2^numShardBits shards, by hash of the key
        strictCapacityLimit - insert to the cache will fail when cache is full

      • LRUCache

        public LRUCache​(long capacity,
                int numShardBits,
                boolean strictCapacityLimit,
                double highPriPoolRatio)
        Create a new cache with a fixed size capacity. The cache is sharded to 2^numShardBits shards, by hash of the key. The total capacity is divided and evenly assigned to each shard. If strictCapacityLimit is set, insert to the cache will fail when cache is full. User can also set percentage of the cache reserves for high priority entries via highPriPoolRatio. numShardBits = -1 means it is automatically determined: every shard will be at least 512KB and number of shard bits will not exceed 6.
        Parameters:
        capacity - The fixed size capacity of the cache
        numShardBits - The cache is sharded to 2^numShardBits shards, by hash of the key
        strictCapacityLimit - insert to the cache will fail when cache is full
        highPriPoolRatio - percentage of the cache reserves for high priority entries

    • Method Detail