[ZODB-Dev] Advice on whether to run relstorage database and Zope on different servers

[Anthony Gerrard]

Hi,

We've been successfully running Plone 3.3 + Zope 2.10 + Relstorage + MySql for a couple of years now.  We're running low on memory on our existing server (which has numerous other services on it) and will soon need to deploy an additional Plone 4.1 + Zope 2.13 + Relstorage + Mysql environment.  We've been using virtual environments since September.

For the purposes of this discussion please assume we don't have the option of increasing the memory on our existing server and so need to add a new one.Some questions I'd really appreciate your help with please:

* I'm familiar with enterprise environments where you would have an "app server" and a "database server" but are there any advantages to putting Zope and MySQL on different servers?
* I'd expect a performance hit if we run Zope + MySQL on separate servers but is this hit manageable?
* Can we put anything in place to mitigate this?
* Would you simply recommend having the existing mysql + zope on one server and the new mysql + zope on the other?

Thanks in advance

Anthony
_______________________________________

Anthony Gerrard
Email: anthonygerrard at gmail.com
http://www.sponsorachild.org.uk