[Dovecot] Newbie index infrastructure and location questions

[Stewart Dean]

I've been lurking for a year or more and am now actually bringing 
Dovecot up (it seems that any time I make a serious effort at this, 
something else falls in the pot and I have to give it up yet again).
Index questions:
I understand the indices should be placed in a non-file-system-quoted 
place.  I have in mind to create /var/dcndx
1) Roughly how much space do indices take up (so I can size space for a 
directory for them)?  I have 4000 users, average mbox inbox size is 
5.5MB (totalling 22GB), the number of messages/user mailbox I'd guess to 
average around 100 and go as high as 5000.  They have maybe as much as 
3x times space and messages in folders, though I guess the average is 
about half that of INBOX
2) I'm clear that DC will automagically create the index files, but
a) do I have to create a subdirectory for each user, ex: /var/dcndx/user1
b) Is there one index file theat handles a user's mailbox and folders or 
a separate one for each?

-- 
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Stewart Dean, Unix System Admin, Henderson Computer Resources 
Center of Bard College, Annandale-on-Hudson, New York  12504  
sdean at bard.edu  voice: 845-758-7475, fax: 845-758-7035