MemCached Non-Traditional Usage?

[Perrin Harkins]

On 3/20/07, Geoffrey Mina <geoffreymina at gmail.com> wrote:
> I am hoping to implement this as a solution for a telephony platform.  I
> have a cluster of servers which need to share information with each other.

That sounds like the application that MySQL Cluster was created for.

> I am looking to store information into memcached with server 1 and retrieve
> it with server 2... no database involved at any point.  The data that would
> be existing in cache would be true transient data that would exist for
> seconds or minutes and then would be flushed from the shared memory/cache.

If memcached runs out of free RAM, it will silently drop your data.
If the daemon stops for any reason, all of your data will be lost.

The question is, if some of this data silently went away, would your
application be in trouble?  If the answer is yes, use something else
like MySQL Cluster.  The intended application for memcached (caching)
doesn't care if it loses some data now and then.

> If I have 3 memcached servers and 10 telephony servers running the client
> API (connecting to all 3)

Since the data will be spread between the three with no redundancy,
you are increasing the change of losing data by running more of them
rather than decreasing it.

- Perrin