Package org.apache.accumulo.core.spi.cache

Interface BlockCacheManager.Configuration

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      long getBlockSize()
      Before Accumulo's cache implementation was configurable, its built in cache had a configurable block size.
      long getMaxSize​(CacheType type)
      Before Accumulo's cache implementation was configurable, its built in caches had a configurable size.
      Map<String,​String> getProperties​(String prefix, CacheType type)
      This method provides a way for a cache implementation to access arbitrary configuration set by a user.

    • Method Detail

      • getMaxSize

        long getMaxSize​(CacheType type)
        Before Accumulo's cache implementation was configurable, its built in caches had a configurable size. These sizes were specified by the system properties tserver.cache.config.data.size, tserver.cache.config.index.size, and {code tserver.cache.config.summary.size}. This method returns the values of those settings. The settings are made available, but cache implementations are under no obligation to use them.

      • getBlockSize

        long getBlockSize()
        Before Accumulo's cache implementation was configurable, its built in cache had a configurable block size. This block size was specified by the system property tserver.default.blocksize. This method returns the value of that setting. The setting is made available, but cache implementations are under no obligation to use it.

      • getProperties

        Map<String,​String> getProperties​(String prefix,
                                       CacheType type)
        This method provides a way for a cache implementation to access arbitrary configuration set by a user.

        Returns all Accumulo properties that have a prefix of tserver.cache.config.<prefix>.<type>. or tserver.cache.config.<prefix>.default. with values for specific cache types overriding defaults.

        For example assume the following data is in Accumulo's system config. 

         tserver.cache.config.lru.default.evictAfter=3600
 tserver.cache.config.lru.default.loadFactor=.75
 tserver.cache.config.lru.index.loadFactor=.55
 tserver.cache.config.lru.data.loadFactor=.65

        If this method is called with prefix=lru and type=INDEX then it would return a map with the following key values. The load factor setting for index overrides the default value. 

         evictAfter=3600
 loadFactor=.55
        Parameters:
        prefix - A unique identifier that corresponds to a particular BlockCacheManager implementation.