Gregory K. Ruiz-Ade wrote:
The primary difference seems to be that we're using NFS here
<snip> 8<
Mailbox formats are mbox.
Those are the two most important pieces of information in your message (IMHO). mbox is always slower than maildir when the filesize exceeds the operating memory for the server (i.e. it cannot be mmapped). NFS will always be slower than "local" access, even on NetApp's supposed 'high-performance' NFS. The combination is deadly, since every message stored in Trash requires copying the entire mbox file and appending the new message, then deleting the original and renaming the new file in its place.
Then there is the additional performance drag caused by Dovecot rewriting the index, as well as Thunderbird (which you should really upgrade to 1.5) keeping its local index up to date. You can confirm this by emptying your trash folder and seeing if the performance changes (which I am confident it will).
There are three things you can do to improve performance:
- Upgrade to Dovecot 1.0 stable (or even Beta2);
- Switch to Maildir (instead of mbox);
- Install a SAN (instead of the NFS mounted NAS).
The last is the only one that costs you hard capital; the other two only involve your time, which as we all know, doesn't count. ;-)
HTH
John
-- John Peacock Director of Information Research and Technology Rowman & Littlefield Publishing Group 4501 Forbes Boulevard Suite H Lanham, MD 20706 301-459-3366 x.5010 fax 301-429-5748