Jeff Garzik writes:
> > Comments?
>
> With GigE you want 64-bit anyway. Heavily loaded GigE networks will
> turn over 32-bit counters pretty often.
Yes 32 bit counters w. GIGE is real pain. at 5 min sampling rate byte
counters wraps just above 100 Mbps.
Illstrated by a Linux GIGE router now constanly at about 200 Mbit/s
pps counters fine they dont wrap yet :-)
http://robur.slu.se/traffic-mrtg/archive-r1-pps.html
To compare with were the output byte counters do wrap so they more or
less useless.
http://robur.slu.se/traffic-mrtg/archive-r1.html
Of one decrease the sampling rate but it only very a short time solution
and this overhead has to traded with checking carry overflow overhead.
> Further, yet another reason is that newer NICs store the stats in 64-bit
> numbers, in hardware.
Yes.
> I don't think this was discussed with DaveM, but since the SNMP MIBs use
> 64-bit numbers and newer GigE cards use 64-bit numbers, we pretty much
> decided at the kernel meeting that netdev_stats should go to 64-bit.
I put my vote there too.
Cheers.
--ro
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