An update:

On Mon, Jul 24, 2006 at 01:16:30PM +0300, Jukka Marin wrote:
> I'm setting up this SMP amd64 system, now running the i386 port, -current
> kernel and binaries built yesterday.
> 
> I have a large raidframe "disk" (raid1, two SATA disks).  I used tar
> to archive some 30 GB of files into a partition (no softdep) on the
> raid disk.  The source files were read over NFS.  Nothing else (but
> systat) was running on the system.
> 
> A few times during the copy, the system froze completely and then
> woke up again.  When this happens, the system does not respond to
> ping, it doesn't update the systat display or do anything visible.
> During the copy, over 40 ping packets were lost.

The system does _not_ freeze, but the network interface does.

I had been using the amd64 system over LAN only, so when the network
interface paused, my ssh connection (and ping etc) was also paused.

Sorry for spreading misinformation about this ;)

This what dmesg says about the networking hardware:

nfe0 at pci0 dev 10 function 0APCH: Picked IRQ 21 with weight 1: ioapic0 pin 21 (irq 10), address 00:e0:81:55:90:81
makphy0 at nfe0 phy 1: Marvell 88E1111 Gigabit PHY, rev. 2
makphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT,
1000baseT-FDX, auto

  -jm