samba - Jan 2010 - Win7 can and cannot join domain; speed issues? (tests to /dev/zero & /dev/null?)

I've made some pseudo progress  .. I deleted my DNS domain name from my 
client -- after that, I was able to get a message (Welcome to Bliss Domain) --
followed by 'Domain join failed, you will not be in the Domain.  Reboot now
to activate your new domain name.

Upon reboot, it thinks I am in Bliss domain, BUT it acts completely
unjoined -- no domain groups in group list selections, Shares won't
work -- says I need permission from 'Domain\me', or the
funniest (if I it wasn't also sad), was when I connected to the share
as ClientWorkstation\me, it then told me I couldn't alter
files w/o permission from Athena\me.  Um...I am me?...and I'm on my
workstation, but it thinks I need permission from me?  What's up with
that!

Anyways, back to workgroup Bliss, and file sharing is normal again.

Also have an ongoing oddity --  read/write speed to a network share.

I can't figure out why it's so slow.  Writes are faster than reads.

My tests are a bit weird.  To test out write, I write to /dev/null
on the target sys, and to test read, I'm reading from /dev/zero.

Locally, these copies return instantaneously.  But over the network
I get about 34MB/s read, and 39MB/s write.  But oddly smbd is 
nearly 100% cpu bound.  I was using 'dd' with a 1GB block size.
So shouldn't 'smbd' usually have been asleep awaiting I/O completion
(which is near instantaneous).  I'd expect to be getting more along
the lines of 60-70MB/s R+W (Gigabit network with large packet (9014) enabled. 
It's a bit faster than standard packets by about 10%.  But
that's not real exciting...

Shouldn't tests to a remote /dev/zero and /dev/null be valid for
testing a no-filesystem load raw transfer rate?

-linda