[Dovecot] SSD drives are really fast running Dovecot

[Frank Cusack]

On 1/16/11 2:10 PM -0600 Stan Hoeppner wrote:
> Using XFS with delayed logging mount option (requires kernel 2.6.36 or
> later).
...
> Using the delayed logging feature, filesystem metadata write operations
> are pushed almost entirely into RAM.  Not only does this _dramatically_
> decrease physical metadata write IOPS but it also increases metadata
> write performance by an order of magnitude.  Really shines with maildir,

ext3 has the same "feature".  It's fantastic for write performance,
and especially for NFS, but for obvious reasons horrible for reliability.
I'm sure XFS fixes the consistency problems of ext3, ie on power failure
your fs is still consistent, but clearly this strategy is not good
for a mail store, ie where you also care about not losing data.

I personally like ZFS with a SLOG for the sync writes.  Plus you get
the extra guarantees of zfs, ie it guarantees that your disk isn't
lying to you.