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To: Justin Hibbits <jhibbits@freebsd.org>
Subject: Re: newcons fb driver
In-reply-to: <CAHSQbTBTq6EKD_crn=rvbeUcAEBn7E+=U8wRHeqchazF1LhjwQ@mail.gmail.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Mon, 03 Mar 2014 19:50:11 +0000
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In message <CAHSQbTBTq6EKD_crn=rvbeUcAEBn7E+=U8wRHeqchazF1LhjwQ@mail.gmail.com>
, Justin Hibbits writes:
>On Mon, Mar 3, 2014 at 8:49 AM, Kurt Lidl <lidl@pix.net> wrote:

>All great knowledge, but really only answers half of what I'm looking
>for (always good to know potential pitfalls).  Assuming a
>tunable/sysctl is added, what's the best way to optimize from my
>original post?  Use a backing buffer (potentially with a tunable to
>not)?  Or assume we don't support background images, and write the
>background color in the masked pixels?

You should probably drop sos@ aka Søren Schmidt an email, he did
syscons and has 10+ years experience in this stuff.

One advantage of a backing buffer is that you can implement things
like the 1000 line scroll buffer syscons did etc, I personally use
that a lot to see dmesg output etc.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.