e-Book - Redis in Action

This book covers the use of Redis, an in-memory database/data structure server.
  • Foreword
  • Preface
  • Acknowledgments
  • About this Book
  • About the Cover Illustration
  • Part 1: Getting Started
  • Part 2: Core concepts
  • Part 3: Next steps
  • Appendix A
  • Appendix B
  • Buy the paperback

    9.1 Short structures

    The first method of reducing memory use in Redis is simple: use short structures. For
    LISTs, SETs, HASHes, and ZSETs, Redis offers a group of configuration options that
    allows for Redis to store short structures in a more space-efficient manner. In this section,
    we’ll discuss those configuration options, show how to verify that we’re getting
    those optimizations, and discuss some drawbacks to using short structures.

    When using short LISTs, HASHes, and ZSETs, Redis can optionally store them using
    a more compact storage method known as a ziplist. A ziplist is an unstructured representation
    of one of the three types of objects. Rather than storing the doubly linked
    list, the hash table, or the hash table plus the skiplist as would normally be the case for
    each of these structures, Redis stores a serialized version of the data, which must be
    decoded for every read, partially re-encoded for every write, and may require moving
    data around in memory.