[Dovecot] dovecot and nfs readdir vs readdirplus operations

[Timo Sirainen]

On 4.7.2012, at 21.49, Angel L. Mateo wrote:

> 	Although nfs configuration is the same, there are a lot of differences on readdir vs readdirplus nfs operations. In fact, in the old one we have 12% readdir operations and 3% of readdirplus. And in the new one we have 46% of readdirplus and no readdir operations.

I'm not entirely sure, but I think it's the kernel that decides if readdir or readdirplus is used and Dovecot can't affect that decision. (Unless maybe kernel does some heuristics.)

> PS: I have attached doveconf -n of the new server.


At least this reduces performance:

mail_nfs_storage = yes

Also maildir_very_dirty_syncs=yes improves performance by reducing readdirs. It's safe to use as long as only Dovecot is reading the Maildir.