choosing a file system

[Rob Mueller]

>> We've found that splitting the data up into more volumes + more cyrus
>> instances seems to help as well because it seems to reduce overall
>> contention points in the kernel + software (eg filesystem locks spread
>> across multiple mounts, db locks are spread across multiple dbs, etc)
>
> Makes sense.  Single cyrus env here, might consider that in the future.
> At
> that point though, I'd probably consider Murder or similar.

That should work fine as well.

I believe murder just does two main things.

1. It's merges the mailboxes.db from each instance into each other instance,
so you end up with just one giant single namespace
2. It proxies everything (imap/pop/lmtp) as needed to the appropriate
instance if it's not the local one

We don't use murder as we don't really need (1), and we do (2) ourselves 
with a combination of nginx and custom lmtpproxy tool.

Rob