# Package org.apache.sysds.runtime.controlprogram.caching

Interface Summary
CacheBlock<T>: Interface for all blocks handled by lazy write buffer.

Class Summary
ByteBuffer: Wrapper for WriteBuffer byte array per matrix/frame in order to support matrix/frame serialization outside global lock.
CacheableData<T extends CacheBlock<?>>: Each object of this class is a cache envelope for some large piece of data called "cache block".
CacheBlockFactory: Factory to create instances of matrix/frame blocks given internal codes.
CacheDataInput
CacheDataOutput: Custom DataOutput to serialize directly into the given byte array.
CacheEvictionQueue
CacheMaintenanceService
CacheStatistics: This singleton provides basic caching statistics in CP.
FrameObject
LazyWriteBuffer
MatrixObject: Represents a matrix in control program.
PageCache
TensorObject
UnifiedMemoryManager: Unified Memory Manager - Initial Design Motivation: The Unified Memory Manager, henceforth UMM, will act as a central manager of in-memory matrix (uncompressed and compressed), frame, and tensor blocks within SystemDS control program.

Enum Summary
CacheableData.CacheStatus: Defines all possible cache status types for a data blob.
CacheStatistics.Stat
LazyWriteBuffer.RPolicy
MatrixObject.UpdateType