Re: forcedeth ipv6 mcast packet loss

From: Joachim Worringen
Date: Thu Sep 24 2009 - 02:39:14 EST

Christian Tramnitz schrieb:
I can reproduce this behaviour on (x86-32) vanilla 2.6.29, 2.6.30 and 2.6.31.
I have no clue what to do next, I assume there is a problem with the forcedeth driver...

It's either the driver or the hardware - I suspect the latter. I experienced significant problems with Nvidia Ethernet hardware and the nforcedeth driver under load, in many machines.

My recommendation is to use another NIC if possible. I then switchted to Intel, which worked flawlessly in the same machines.

Alternatively, you could try to increase the kernel buffers for network packets as in your case, you seem to loose the packets further up:
# sysctl -w net.core.rmem_max=8388608
# sysctl -w net.core.wmem_max=8388608
# sysctl -w net.core.rmem_default=65536
# sysctl -w net.core.wmem_default=65536

There are buffers for ipv4 like you can tune with
# sysctl -w net.ipv4.tcp_rmem='4096 87380 8388608'
- I don't know if this is the same for ipv6.


Joachim Worringen
Senior Performance Architect

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