Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 15 Sep 2002 23:53:44 +0200
From:      Marko Zec <zec@tel.fer.hr>
To:        Andrew Stesin <stesin@breaker.tormoz.net>
Cc:        freebsd-stable@FreeBSD.ORG
Subject:   Re: Bug? VLANs, fxp, Catalyst and link0 story
Message-ID:  <3D850168.2A24346@tel.fer.hr>
References:  <20020915182028.O1070-100000@chour.hostmaster.net.ua>

next in thread | previous in thread | raw e-mail | index | archive | help
Andrew Stesin wrote:

> >  > Another problem is: as soon as I remove "link0" from ifconfigs for
> >  > "carrier" interfaces fxp0 and fxp1 - again it doesn't work.
> >
> > That's interesting.  I've never needed link0 for any fxp cards before,
> > and I'm not really sure what the microcode is good for.  (Sure, I've
> > read the docs, but they don't say _when_ you should use it and what the
> > advantages and disadvantages are.)

You can find a short discussion pro and contra some aspects of interrupt
coalescing at http://www.tel.fer.hr/zec/papers/zec-mikuc-zagar-02.pdf
(the
measurements were performed on FreeBSD 4.4 with fxp microcode). The docs
for
the original fxp patch are also slightly more detailed than the current
manpage. See http://www.tel.fer.hr/zec/BSD/fxp/index.html

Regards,

Marko

> The only visible (for now) difference is appearance of lines:
>
> fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
> fxp0: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
> fxp1: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
> fxp1: Microcode loaded, int_delay: 1000 usec  bundle_max: 6
>
> at the bottom of kernel boot output. I didn't do any testing, though -
> maybe it will either reduce interrupt load or somewhat increase
> throughoutput? Or maybe loading microcode makes Intel chips behave in
> somewhat more "standard", expected way?

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-stable" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3D850168.2A24346>