Simple questions from memcached newbie

[Andy]

On Wed, 2006-10-11 at 12:45 -0700, Ask Bjørn Hansen wrote:
> On Oct 11, 2006, at 11:29 AM, Jeetendra Mirchandani wrote:
> 
> > Going a little off topic here, has somebody worked on writing a data
> > redundancy layer over memcached?
> >
> > What I would love to have is memcached servers talking to each other
> > maintaining replicas, so that even if a server goes down, the data is
> > not lost.
> 
> The default reply is "you want MySQL Cluster".
> 
> Since people keep wanting to use the memcached interface for this,  
> maybe MySQL Cluster (as in NDB) could be a storage backend for  
> memcached.

The difference here is that memcached is at least an order of magnitude
easier to setup and maintain than MySQL cluster, and adding an
additional "storage backend" on memcached means you need to maintain two
sets of software (memcached and mysql cluster) rather than one (for no
advantage really, since NDB is a memory based store, just like
memcached) resulting in increased complexity.

A memcached client interface on MySQL would help people transition,
ahem, away from memcached (or it might bring users into the fold).

Memcached remains dead simple to setup and dead simple to use and dead
simple to make more "reliable", by either changing your client code to
make the client "smarter" (to send/try multiple servers, for example),
or by adding additional nodes to reduce the percentage of data on any
single node to whatever low amount you feel is appropriate.  These are
most definitely _virtues_ of memcached.

-- 
Andy <memcached at thwartedefforts.org>