• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Caching technology comparison
 

Caching technology comparison

on

  • 4,153 views

Dynacache and Data Replication Service vs Memcached

Dynacache and Data Replication Service vs Memcached

Statistics

Views

Total Views
4,153
Views on SlideShare
2,855
Embed Views
1,298

Actions

Likes
0
Downloads
60
Comments
0

37 Embeds 1,298

http://wasdynacache.blogspot.com 731
http://wasdynacache.blogspot.in 165
http://wasdynacache.blogspot.it 61
http://wasdynacache.blogspot.com.au 51
http://wasdynacache.blogspot.ca 43
http://wasdynacache.blogspot.de 32
http://wasdynacache.blogspot.co.uk 32
http://wasdynacache.blogspot.ru 18
http://wasdynacache.blogspot.com.es 18
http://wasdynacache.blogspot.nl 15
http://wasdynacache.blogspot.fr 15
http://wasdynacache.blogspot.hk 13
http://wasdynacache.blogspot.com.br 11
http://wasdynacache.blogspot.sg 11
http://wasdynacache.blogspot.se 8
http://wasdynacache.blogspot.tw 7
http://wasdynacache.blogspot.co.nz 7
http://wasdynacache.blogspot.kr 6
http://wasdynacache.blogspot.ch 6
http://wasdynacache.blogspot.dk 5
http://wasdynacache.blogspot.jp 4
http://wasdynacache.blogspot.be 4
http://wasdynacache.blogspot.ae 3
http://wasdynacache.blogspot.mx 3
http://wasdynacache.blogspot.ie 3
http://wasdynacache.blogspot.pt 3
http://wasdynacache.blogspot.sk 3
http://wasdynacache.blogspot.com.ar 3
http://wasdynacache.blogspot.no 3
http://www.docseek.net 2
http://wasdynacache.blogspot.ro 2
http://wasdynacache.blogspot.fi 2
http://webcache.googleusercontent.com 2
http://wasdynacache.blogspot.gr 2
http://wasdynacache.blogspot.com.tr 2
http://wasdynacache.blogspot.cz 1
http://wasdynacache.blogspot.co.il 1
More...

Accessibility

Categories

Upload Details

Uploaded via as OpenOffice

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment
  • Last update:

Caching technology comparison Caching technology comparison Presentation Transcript

    • Caching Technologies for Java Applications
      Martin Presler-Marshall ICS Performance
    09/30/2011
    • Technologies
    • General object cache attributes
    • Memcached
    • DistributedMap (part of Dynacache)
    • General Object Cache Characteristics
    • An object cache is a Key-Value lookup table
      • Similar to java.util.Hashtable
    • Have configurable maximum sizes
      • May be configured number of cache entries or memory size
      • Objects typically discarded on least-recently-used policy when cache is full
        • Some caches may offer other algorithms, such as priority-based schemes
    • Have configurable lifetimes per cache entry
      • Items are automatically discarded once lifetime is exceeded
  • Overview: Cache Instances
    • A cache instance is a logical grouping of cache keys & values
    • Identical keys in two separate cache instances do not collide
    • Cache statistics can typically be monitored on an instance level
    • Support for creating multiple instances varies by cache implementation
    • Overview: Memcached
    • “ Free & open source, high-performance, distributed memory object caching system” (from memcached.org)
    • Main components:
      • memcached server – standalone server storing cached items
        • Each cluster of servers is a single cache instance
        • To run multiple instances, must run multiple servers on each node
      • memcached client software
        • Available for multiple programming languages
        • Keys & values must be serialized, then transmitted over TCP/IP
    • Cluster design:
      • Client uses hashing algorithm to assign keys to servers
      • Each key is cached on at most one server
      • Explicit invalidations go only to the server which should store that key
    • Overview: DistributedMap
    • Built-in component in WAS Network Deployment
      • Only available to Java clients
    • Content is cached in JVM memory
      • Cache operations are POJO calls
    • Multiple cache instances can be created simply
      • Each is treated separately for monitoring, synchronization, LRU and invalidation
    • Cluster design:
      • Cache keys may be cached in multiple nodes
      • Explicit invalidation notifies peers to discard the cache key
      • Option available to push entries to peers on cache insert
  • Advantages: Dynacache
    • Fast cache operations - the key raison d'etre for a cache
      • Lookups through POJO calls - no network delays
      • No serialization/ deserialization of keys and values – lower CPU consumption
    • Successful experience with many IBM products & customers
      • We know how to use it well
    • Mature, supported part of WAS
    • Integration points: Extreme Scale, OpenJPA
    • Flexibility
      • Easy support for multiple cache instances
      • Priority-based LRU algorithm
      • Disk offload
    • Monitoring/management tools: (PMI, Mbean, Cache Monitor)
  • Advantages: Memcached
    • Does not consume memory in Java heap
      • This is less important on a 64-bit JVM
      • We've successfully run WAS apps with 6+GB heaps
    • Active community support
      • ...though available documentation is not great
    • Usable in Tomcat, WAS CE, php applications
    • Used successfully by multiple public sites
    • Single instance of each cache key
      • No peer-to-peer traffic on invalidations
      • A key inserted by one node is immediately available to all peers
        • Typically will increase hit rates
    • Cache size increases as nodes are added
    • Free tools exist for monitoring
      • ...but somewhat hard to use
  • Open Questions
    • Need some direct performance comparisons
      • Have done some limited benchmarking of memcached using various clients
      • Small-scale (single server, small cachesize)
    • Monitor memcached servers in LotusLive performance environment
      • May provide useful data on memcached performance in a nearly-real-world use case