<p>We need to implement a large-scale key-value store (let's say up to 500GB) and BerkeleyDB seemed like it might be a decent option, but we would really like it to be network accessible. This led me to look at memcachedb. I haven't found much on the web where people talk about actual experiences with memcachedb, so my questions are, if you've used memcachedb:</p>

<ul>
<li>would you recommend using it for a large k-v store?</li>
<li>if not, why not?</li>
</ul>

<p>Thanks in advance!</p>

<p>Francis</p>

I have used memcached a little bit in one of my projects. I think it's a very efficient and scalable caching platform. By changing small configurations, you're able to replicate the cached objects in more than one server. Facebook uses memacached for their in-memory storage and it's a large scale entity on the web. This gives a thumb up for memcahced.
The only problem I faced in implementation is that doesn't automatically accept objects to store. You will need to serialize the objects before storing which may be a little bit confusing at the beginning.
FYI, there is a nother caching platform produced by Microsoft called: Velocity. You may need to take a look on it:
http://www.microsoft.com/downloads/details.aspx?FamilyId=B24C3708-EEFF-4055-A867-19B5851E7CD2&displaylang=en