Simple questions from memcached newbie

[Jeremy Blain]

howard chen wrote:

> 1. If the memcached server goes down, the time is finding where the
> server is alive will be a bottom neck to your application?
>
> e.g.
>
> my $obj = $::MemCache->get("foo:$foo_id"); // your application will
> eventually die at this, if memcached down?
>
You should just get back undefined.  Your application should not die.

>
> 2. How to calculate the efficiency of memcached server, e.g. given
> 1000 KB of memory allocated, how many % are actually used for storing
> the data itself?
>
It depends on what you're storing really.  Our use is at about  75%.
(1 gig = 750mb stored).  Your usage can vary depending on the size of 
objects
you store.  Newer memcached code is supposedly more efficent, but I havn't
tested it personally.

> 3. in a distributed environment, i have say 2 memcached server, if the
> item is no longer valid on one server, how much time is needed for
> another server to know this?
>
Your data will only be in one server.  Which server to put the item in 
is chosen by
the client.