em0, polling performance, P4 2.8ghz FSB 800mhz
don at sandvine.com
Sat Feb 28 21:08:32 PST 2004
> > You may need to increase the MAX_RXD inside your em driver
> to e.g. 512.
> I didn't know if my card had a buffer bigger than the default
> 256. I can
> increase it, but I didn't know how to determine how big a MAX_RXD my
> card would support. When the system was under load, it was generating
> 2xHZ clock ticks (2000 when HZ was 1000) is that normal?
max_rxd is not a function of the card. its the system ram
you devote to dma buffers.
Too big will cause problems since it will flush through the
you should get (vmstat -i) a clk rate that exactly matches
More information about the freebsd-hackers