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Re: more UDP packet loss?

Urban Boquist wrote:
> some other people have reported UDP packet loss between domU and dom0
> (in bridge mode) but I understood that has mostly been under high
> traffic load? I seem to get loss also with no load at all.
> Every time I start a domU I see lost DHCP replies and lots of NFS
> retransmits. This is for a domU with root on NFS but I get the DHCP
> problems also for a domU on local disk. At the same time the other
> running domU:s seem to "freeze". After the domU is started it uses NFS
> over TCP and that seems to work better.
> Below are packet captures during boot, up to the NFS mount root
> call. The DHCP offers come back from the DHCP server on physical wm0
> but the first 7 never reaches the domU XVIF interface. Netstat shows
> no packet loss.
> This is on a 8GB Quad core Xeon system - with zero CPU load in dom0
> and a couple of other domUs. Week old -current amd64 dom0.
> I tried increasing the UDP send/receive buffers in dom0 but it made no
> difference.
> Any ideas?

Does it happen only during domU start, or also during normal operation, like when DHCP requests new leases?

Jean-Yves Migeon

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