Transparent failover and restore?

[Larry Leszczynski]

Hi Gregory -

On Sat, 18 Dec 2004, Gregory Block wrote:

> On 17 Dec 2004, at 21:09, Brad Fitzpatrick wrote:
> > Guys,
> >
> > If you want to use memcached as a data store instead of a /cache/, then
> > use MySQL Cluster:
> >
> >    http://www.mysql.com/cluster/
> >
> > It was designed for that, doing the whole redundant storage and
> > two-phase
> > commit thing, while memcached was designed to be a cache.
> >
>
> No, I think the point is quite simple, actually;
>
>   - we cache things because the cost of generating them is too high to
> do in bulk
>   - on large-scale systems, or heavily used systems, the cost of losing
> a server can bring down the system
>
>
> The problem can be mitigated, with additional runtime overhead by
> clients, with some work to ensure that there's better distribution of
> single items of information within the cache network.  Moving each
> information onto two servers in the network immediately makes the
> entire system less likely to fall over dead; it also reduces the amount
> of "actual" free space in the cluster you add when you add a node, but
> that's just efficiency losses.  People with RAID will already be
> familiar with that kind of logic.

Nobody would argue those points, but I think the point of Brad's mail was
that there's no need to reinvent the wheel since MySQL cluster satisfies
all those needs.


Larry