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Re: Using event counters with network interfaces, is there a reason they're all ifdefed out of mainline use?

        hello.  I'm interested in seeing detailed errors like CRC, frame,
underrun and overrun error counts.  Further investigation reveals that
drivers that came later in the game, i.e. nfe(4) and age(4)  don't have
latent support for these counters, but it looks fairly easily added.
        While I understand performance considerations are necessary, the
counters I'm proposing to add should be fairly low frequency events, since
we already count bytes and packets in and out, and if the performance of
the event counters infrastructure were really a problem, we should be
taking a hit because many of the interrupt counters are using it to keep
their statistics.  While I don't aspire to be like Linux, Linux does report
these kinds of errors, as do most modern networking devices.  I think we
should hav the capability of tracking such errors, and I think we can for
little effort and almost no performance loss.
        Since there's been some nervousness expressed to me about performance
hits, I propose to do one driver at a time, do some testing of mine, then commit
those changes to the tree.  We can either set the COUNT_INTERFACE_EVENTS
option to true at that time, or have a self selected group do some early
testing.  However, it is my  wish to have this higher granularity of error
tracking turned on by default in future releases of NetBSD.


On Dec 11,  1:18pm, Manuel Bouyer wrote:
} Subject: Re: Using event counters with network interfaces, is there a reas
} On Sat, Dec 10, 2011 at 05:04:41AM -0800, Brian Buhrow wrote:
} >     Hello.  I notice that most, if not all, of the network drivers in
} > NetBSD have interface counters which they use to track things like
} > collisions, CRC errors, framing errors, etc.  It looks like these counters,
} You have these informations (with less granularity I admit) in
} netstat -i outtput.
} -- 
} Manuel Bouyer <>
}      NetBSD: 26 ans d'experience feront toujours la difference
} --
>-- End of excerpt from Manuel Bouyer

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