Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 7 Apr 2023 13:08:04 -0600
From:      Warner Losh <imp@bsdimp.com>
To:        Poul-Henning Kamp <phk@phk.freebsd.dk>
Cc:        Alan Somers <asomers@freebsd.org>, FreeBSD CURRENT <freebsd-current@freebsd.org>
Subject:   Re: textdumps are too slow
Message-ID:  <CANCZdfroaGxPLT_PkhqXqJ07JovCv-TChf5AecxquPG6SKo=eA@mail.gmail.com>
In-Reply-To: <202304071220.337CK7XH083443@critter.freebsd.dk>
References:  <CAOtMX2j-Muz2uFE5YkYQ7atvQO9VrT4pDdvVnay-S%2BNi6rZNMQ@mail.gmail.com> <202304070922.3379MVW5077791@critter.freebsd.dk> <CAOtMX2go2PKC-hDOncJjHxfZRSY3AMGRSGXDF20O%2BzjFoQs=uA@mail.gmail.com> <202304071220.337CK7XH083443@critter.freebsd.dk>

next in thread | previous in thread | raw e-mail | index | archive | help
--0000000000004af33c05f8c3bf5f
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Fri, Apr 7, 2023 at 6:20=E2=80=AFAM Poul-Henning Kamp <phk@phk.freebsd.d=
k> wrote:

> --------
> Alan Somers writes:
> > On Fri, Apr 7, 2023 at 2:22=3DE2=3D80=3DAFAM Poul-Henning Kamp <
> phk@phk.freebsd.dk> wrote:
>
> > > I would expect them to be limited by the serial console speed before
> > > the video system speed ?
> >
> > That was my first guess, too.  But my serial console is 115200 baud,
> > which is faster than the low performance server grade video card.
>
> Ok, that must truly be sucky hardware...
>

That's 10x slower than 1990s era VGA cards then... 115200 is 11k characters
a second,
and FreeBSD on 1990s era VGA cards was in excess of 1MB/s, faster if not a
pure ISA
card... Video hardware that's slower than *THAT* likely indicates a big big
problem in
our video stack.

Warner

--0000000000004af33c05f8c3bf5f
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div dir=3D"ltr"><br></div><br><div class=3D"gmail_quote">=
<div dir=3D"ltr" class=3D"gmail_attr">On Fri, Apr 7, 2023 at 6:20=E2=80=AFA=
M Poul-Henning Kamp &lt;<a href=3D"mailto:phk@phk.freebsd.dk">phk@phk.freeb=
sd.dk</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"ma=
rgin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:=
1ex">--------<br>
Alan Somers writes:<br>
&gt; On Fri, Apr 7, 2023 at 2:22=3DE2=3D80=3DAFAM Poul-Henning Kamp &lt;<a =
href=3D"mailto:phk@phk.freebsd.dk" target=3D"_blank">phk@phk.freebsd.dk</a>=
&gt; wrote:<br>
<br>
&gt; &gt; I would expect them to be limited by the serial console speed bef=
ore<br>
&gt; &gt; the video system speed ?<br>
&gt;<br>
&gt; That was my first guess, too.=C2=A0 But my serial console is 115200 ba=
ud,<br>
&gt; which is faster than the low performance server grade video card.<br>
<br>
Ok, that must truly be sucky hardware...<br></blockquote><div><br></div><di=
v>That&#39;s 10x slower than 1990s era VGA cards then... 115200 is 11k char=
acters a second,</div><div>and FreeBSD on 1990s era VGA cards was in excess=
 of 1MB/s, faster if not a pure ISA</div><div>card... Video hardware that&#=
39;s slower than *THAT* likely indicates a big big problem in</div><div>our=
 video stack.</div><div><br></div><div>Warner</div></div></div>

--0000000000004af33c05f8c3bf5f--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CANCZdfroaGxPLT_PkhqXqJ07JovCv-TChf5AecxquPG6SKo=eA>