title: REDIS Durability ? how to auto expire data?
body: <p>I use REDIS to store data (string) .
  ex: 
  key "s1" store value "hello world".
  key "s2" store value "bye bye".
  I want s1 auto expire (free memory) after 5 minutes but s2 never expire.
  I use C#, .net 4.0 >> how to code ?.
  thanks</p>