Cache miss stampedes

[dormando]

>  
> I like this.
>  
> Why not include probalistic expirations in the server ?
>  
> Here is a proposal :
> - add a startup flag (ie : -e 60), which activates probalistic 
> expirations (if the flag is not set, the determinnistic logic is used)
> - gets may return a cache miss using the same logic as described here
>  
> Jean-François

Not the best idea... That algorithm is completely dependent on the rate 
of incoming requests. Memcached's options (thankfully!) do not usually 
require on the fly tuning to work.

Putting it into the server half defeats the purpose as well. The point 
of this game is to avoid cache misses and refresh caches to avoid a 
stampede/dogpile/whatever.

-Dormando