On Thu, 2008-12-04 at 23:49 +0100, Moritz Muehlenhoff wrote:
> Does this error still occur with more recent kernel versions?

I've just reran the tests with the same hardware. However the client
machines are tracking testing. The server is running Debian/etch with
2.6.18-6-686 and nfs-common 1:1.0.10-6+etch.1, the clients are running:

host OS kernel nfs-common HW
------ --------------- ------------- ---------------- -------------------
host1 Debian/testing 2.6.26-1-686 1:1.1.2-6lenny1 Dell Optiplex SX280
host2 Debian/testing 2.6.26-1-686 1:1.1.2-6lenny1 Dell Optiplex SX280
host3 Debian/testing 2.6.26-1-686 1:1.1.2-6lenny1 Dell Optiplex SX280
host4 Debian/testing 2.6.26-1-686 1:1.1.2-6lenny1 Dell Optiplex SX270
host5 Debian/testing 2.6.26-1-686 1:1.1.2-6lenny1 Dell Optiplex 745
------ --------------- ------------- ---------------- -------------------

host speed discard nfs nfs write nfs read
Mbit/s MB/s prot MB/s MB/s
----- ----- ------- ----- ---------- ---------
host1 1000 104 udp 25 7
tcp 27 11
host2 100 12 udp 10 1
tcp 10 10
host3 100 11 udp 10 3
tcp 7 5
host4 1000 112 udp 21 8
tcp 22 7
host5 1000 118 udp 35 10
tcp 35 9
----- ----- ------- ----- ---------- ---------

The tests:
- discard:
# dd if=/dev/zero bs=1024k count=1024 | nc -q 0 server discard
- create /tmp/tmpfile:
# dd if=/dev/urandom of=/tmp/tmpfile bs=1M count=1024
- mount /mnt with either of:
# mount server:/share /mnt -t nfs -o rw,udp
# mount server:/share /mnt -t nfs -o rw,tcp
- write and read tests:
# dd if=/tmp/tmpfile of=/mnt/tmpfile bs=8k
# dd if=/mnt/tmpfile of=/dev/null bs=8k

The network was otherwise in normal (not too heavy) use so the results
may be a little off (the NFS performance over TCP on host3 surprised me
a little but I couldn't really get any better numbers than this).

I would say the problem is still there. The machines that run on 100Mbit
have slower read performance when on UDP than on TCP. If you want I can
also test different client/server combinations but that will be in the
new year and these test cost quite some time to execute.

--
-- arthur de jong - arthur@west.nl - west consulting b.v. --



--
To UNSUBSCRIBE, email to debian-kernel-REQUEST@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org