Load Balanced Session State Partitioning

Recently doing some research into getting session state management faster and more stable in an enterprise, load balanced environment. Not claiming to be any more knowledgeable than I was before, but definately more read...

Products:

• http://code.msdn.microsoft.com/velocity/
  http://en.wikipedia.org/wiki/Velocity_(memory_cache)
  http://www.microsoft.com/downloads/details.aspx?FamilyId=B24C3708-EEFF-4055-A867-19B5851E7CD2&displaylang=en
• http://memcached.org/
• http://www.alachisoft.com/ncache/index.html
• http://www.scaleoutsoftware.com/products/state_server.php
• http://sharedcache.codeplex.com/
  http://www.sharedcache.com/

Tutorials:

• http://blog.maartenballiauw.be/post/2007/11/ASPNET-load-balancing-and-ASPNET-state-server-(aspnet_state).aspx
• http://blog.maartenballiauw.be/post/2008/01/ASPNET-Session-State-Partitioning.aspx
• http://blog.maartenballiauw.be/post/2008/01/24/ASPNET-Session-State-Partitioning-using-State-Server-Load-Balancing.aspx
• http://en.aspnet-bhs.info/post/State-Server-Partitioning.aspx
• http://www.theserverside.net/news/thread.tss?thread_id=47330
• http://www.codeproject.com/KB/session/ASPNETSession.aspx
• http://blogs.msdn.com/velocity/archive/2008/06/05/how-to-use-session-store-provider-microsoft-project-code-named-velocity.aspx

Discussions:

• http://stackoverflow.com/questions/2063421/scaleout-vs-ncache
• http://forums.asp.net/t/1030680.aspx
• http://forums.asp.net/t/1210004.aspx
• http://stackoverflow.com/questions/489270/caching-and-session-state-management-using-microsoft-velocity-and-memcached
• http://stackoverflow.com/questions/856959/which-distributed-cache

Of course, once you have your caching up and running you'll want to test it before sticking it in the wild:

• http://predicatet.blogspot.com/2009/09/download-microsoft-web-application.html
• http://support.microsoft.com/kb/231282
• http://www.west-wind.com/presentations/webstress/webstress.htm
• http://ask-leo.com/can_i_monitor_or_control_the_bandwidth_used_on_my_home_network.html
• http://www.softwareqatest.com/qatweb1.html#LOAD

And some further reading, which may get bolstered the longer this post stays alive:

• What a 'Cache' is: http://en.wikipedia.org/wiki/Cache
• "Caching in the distributed environment": http://msdn.microsoft.com/en-us/library/dd129907.aspx
• Memcached Vs Velocity Showdown: http://www.briandrought.com/blog/?p=29

And for those who want to know, my own comparison (please be aware that I have not exhaustively tested all options, this is based on research and some usage):

NCache

• Distributed
• Partitioaned
• Replicated
• Remote clients available
• Expensive
• Failover
• Clustered
• Free developer edition not appropriate for live environments

Memcached

• Free
• Open source
• Distributed
• Not partitioned
• Not replicated
• Servers unaware of each other
• Not clustered
• Least recently used model

Velocity

• Sparsely documented

ScaleOut

•