[CentOS] udp question

[Barry Brimer]

> I use linux as GiGE router and have 6 NIC on it
> Those days the NIC interrupt takes around 100% CPU but the system is 4G memroy and 8 CPU. I can't see any error packet in this NIC interface too
>
> After I block the udp, the %CPU drops. but the UDP only takes around 8M in general
>
> We use UDP traffic for voice.
>
> Do you have any suggestion ?  increase the kernel parameter?

Add the following lines to /etc/sysctl.conf

net.core.rmem_default = 67108864
net.core.wmem_default = 67108864
net.core.rmem_max = 67108864
net.core.wmem_max = 67108864
net.ipv4.tcp_mem = 4096 67108864 67108864
net.ipv4.tcp_rmem = 4096 67108864 67108864
net.ipv4.tcp_wmem = 4096 67108864 67108864
net.ipv4.ip_local_port_range = 32768 65535
net.ipv4.tcp_max_syn_backlog = 8192

After adding these lines, run "sysctl -p"