vge(4) slow at 10baseT

[J.R. Oldroyd]

I have just had occasion to use a vge(4) as an interface to as DSL
modem.

When using the same DSL link with an fxp(4), a dc(4) or an axe(4)
interface, various DSL speed tests on the net show the line at its
correct speed of 1536/384 (up/down).

But on the vge(4) interface downloads are noticably slower, and in
fact, the line tests only as 768/128, i.e., about half speed.

The DSL modem runs at 10baseT half-duplex.

Anyone have thoughts as to why this may be?

	-jr



vge0: <VIA Networking Gigabit Ethernet> port 0xf800-0xf8ff mem 0xfdffe000-0xfdffe0ff irq 18 at device 14.0 on pci0
miibus0: <MII bus> on vge0
ciphy0: <Cicada CS8201 10/100/1000TX PHY> on miibus0
ciphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-FDX, auto
vge0: Ethernet address: 00:40:63:eb:5a:f9

vge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        options=1b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING>
        inet6 fe80::240:63ff:feeb:5af9%vge0 prefixlen 64 scopeid 0x1 
        inet 66.171.79.77 netmask 0xffffffc0 broadcast 66.171.79.127
        ether 00:40:63:eb:5a:f9
        media: Ethernet autoselect (10baseT/UTP)
        status: active