I have not noticed any performance impact whatsoever using encrypted filesystems.
I tried running "top" as I sent some email using mailx, and I was getting over 95% CPU idle,
loads of free memory.
/var/log/mail/info.log seems to be completely contained in syslog, there's no additional information.
The messages I'm sending are all test message: just a few characters to my gmail account.
Looking at the headers, it appears the delay is between my laptop and the SMTP server.
If I send a series of separate messages in a row to my gmail account, it doesn't appear to matter
what the order is ; they all will arrive, but not necessarily in the same order they were sent,
and they take between 3-9 minutes, whereas using KDE/2010, it takes less than 1 minute.
On my desktop, I normally run Slackware. I tried installing LXDE/2011 on the desktop as well,
using unencrypted partitions. I had the same problem with very slow outgoing emails; 5 -9 minutes
each. So I don't now think this has anything to do with encrypted filesystems. I do have sendmail
working fine with KDE/2010 on the laptop and Slackware on the desktop. But I can't figure out why
LXDE/2011 takes 5 minutes instead of 10 seconds.
My wife is taking the laptop over the weekend, so I won't be able to look at it again after tonight for
a while. I'm considering installing KDE on my desktop just to see if there's any difference..
Maybe that's a waste of time, I dunno....
So in short, I don't think this is a problem with encrypted filesystems, sendmail itself, or the way
I'm configuring sendmail, or LXDE, or the kernel, etc. I'm guessing I have configured something wrong
or I'm missing some package perhaps, and I'll be very happy to admit my error if someone can help
me figure out what the devil is causing sendmail to be so darned slow...