Re: Net device byte statistics

["Randy.Dunlap" <rddunlap@osdl.org>]

On Fri, 25 Jul 2003 13:55:14 -0400 Jeff Sipek <jeffpc@optonline.net> wrote:

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| On Friday 25 July 2003 13:20, Randy.Dunlap wrote:
| > Yes, a common solution for this is to use some SNMP agent that does
| > 64-bit counter accumulation.
| 
| Interesting...I haven't thought of SNMP.
| 
| > IETF expects that some high-speed interfaces will have 64-bit
| > counters.  From RFC 2233 (Interfaces Group MIB using SMIv2):
| >
| > <quote>
| > For interfaces that operate at 20,000,000 (20 million) bits per
| > second or less, 32-bit byte and packet counters MUST be used.
| > For interfaces that operate faster than 20,000,000 bits/second,
| > and slower than 650,000,000 bits/second, 32-bit packet counters
| > MUST be used and 64-bit octet counters MUST be used. For
| > interfaces that operate at 650,000,000 bits/second or faster,
| > 64-bit packet counters AND 64-bit octet counters MUST be used.
| > </quote>
| 
| It is just easier to have everything 64-bits.

I think the counterpoint is that if it were easy & safe, it would
already be in the kernel.

| > However, this is a MIB spec.  It does not require a Linux
| > (/proc) interface to support 64-bit counters.
| 
| Agreed, however if we are going to change some counters, we should do it for 
| all of them. (Btw, /proc is not the only point where users can get stats.... 
| there is also /sys and something else...I can't remember now...)

Right, I was just saying that the kernel interface doesn't have
to support 64-bit counters in lots of cases.  That can often be
done in userspace.

--
~Randy
| http://developer.osdl.org/rddunlap/ | http://www.xenotime.net/linux/ |
For Linux-2.6:
http://www.codemonkey.org.uk/post-halloween-2.5.txt
  or http://lwn.net/Articles/39901/
http://www.kernel.org/pub/linux/kernel/people/rusty/modules/