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Date: Mon, 01 Jun 2009 21:31:08 -0700
From: Julian Elischer <julian@elischer.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Monitoring throughput of PCIe lanes
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Jason Chambers wrote:
> Hello all,
> 
> I'm wondering if there is currently a way to monitor the throughput of a
> PCIe lane or group of lanes associated with a device ?
> 
> I've done a little exploring of the source and man pages but have yet to
> find anything that seems to relate in an obvious form.
> 
> I wonder if netgraph could somehow be used for this ?
> 
> 
> Thanks,
> 
> --Jason
> 
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unfortunatly PCIe traffic occurs at a level below that at which
the OS can really monitor.

there would have to be some hardware support I think.

THEORETICALLY you could get every device driver to report back
how much traffic it has sent to each device and you could aggregate
that by bus bt it would be a lot of work and overhead
ad wouldn't really be agood measure of burst throughput...