network speed

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

Any ideas on making this gigabit network transfer go faster?

I am getting 20 MiB/s according to:

  dd if=/dev/rwd0f bs=1m | progress -l 78144512k dd of=/attic/rwd0f.raw bs=1m

where /attic is nfs -T mounted

client and server (both -current/amd64 MP) have
- ip4csum tcp4csum udp4csum checksumming enabled
- net.inet.tcp.recvbuf_auto=1
  net.inet.tcp.sendbuf_auto=1
  net.inet.tcp.recvbuf_max=16777216
  net.inet.tcp.sendbuf_max=16777216

server has a NVIDIA nForce MCP55 Gigabit Ethernet Controller
makphy1 at nfe1 phy 1: Marvell 88E1116 Gigabit PHY, rev. 1
and autoselects 100baseTX full-duplex

client has
wm0 at pci0 dev 25 function 0: 82801I mobile (AMT) LAN Controller, rev. 3
wm0: interrupting at ioapic0 pin 20
wm0: PCI-Express bus
wm0: FLASH
wm0: Ethernet address 00:23:18:e8:76:43
ukphy0 at wm0 phy 1: Generic IEEE 802.3u media interface

Oddity: wm0 claims "media: Ethernet none" - so it is hard to check
its duplex setting.

The two are connected directly by a cross-over cable.

(is ukphy the problem?)

Cheers,

Patrick