[mythtv-users] diskless frontend nfs throughput

[Jim Stichnoth]

On Thu, Aug 6, 2009 at 11:05 AM, Dan Littlejohn<dan.littlejohn at gmail.com> wrote:
> I have a gentoo diskless frontend that mounts using nfs and it seems like
> the throughput of nfs is slow.  iperf show the network able to push 770 Mb/s
> and hdparm shows the sata disk on the server at 90 Mb/s, but doing a dd
> across the network only shows up as 10 Mb/s  (is about 40 Mb/s when the same
> test is done on the server to a third machine).
>
> Odd thing is that the pxeboot mounts nfsver2.  Not sure if this is a problem
> or not, but other mounts after boot mount as nfsver3.  Really seems like it
> is a config problem with nfs somewhere, but I have not found anything that
> makes a difference.  Doing rsize=8k,wsize=8k, noatime, async.  Anyone have
> any tips to look for or is this 10 Mb/s really the throughput I should
> expect for a diskless frontend?

My diskless MythDora 10.21 frontend uses NFS.  I timed a copy of a 4GB
file from the NFS server into /dev/null and got about 41 MB/s (or 330
Mb/s).  This is over a gigabit wired network.  The only special mount
option to speak of is "nolock" presumably because the lockd is not
part of the initrd image.

Jim