Messages in this thread | | | Date | Fri, 25 Jul 2003 10:20:43 -0700 | From | "Randy.Dunlap" <> | Subject | Re: Net device byte statistics |
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On Fri, 25 Jul 2003 12:23:37 -0400 Jeff Sipek <jeffpc@optonline.net> wrote:
| -----BEGIN PGP SIGNED MESSAGE----- | Hash: SHA1 | | On Friday 25 July 2003 03:03, Denis Vlasenko wrote: | > I sample the data every minute. Will need to do it much more often | > on 10ge ifaces, when those will appear at my home ;) | | Speed Time for one overflow | | 10Gbits/s => 3.436 seconds | 1Gbit/s => 34.36 seconds | 100Mbits/s => 343.6 seconds | | > Or we will need 64bit counters then. | | For anything up to (and including) 1GBit/s it is possible to do in easily in | userspace, but then were are getting into an area where a program would have | to check the files every 3 seconds (and a bit of load could delay it long | enough for an overflow to happen.)
Yes, a common solution for this is to use some SNMP agent that does 64-bit counter accumulation.
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>
However, this is a MIB spec. It does not require a Linux (/proc) interface to support 64-bit counters.
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