serial console slow

root (root@Elf.ucw.cz)
Fri, 9 Nov 2001 10:21:41 +0100


Hi!

> I tried to boot my kernel using the serial console, using the
> console=ttyS0,115200 (it does the same thing with 9600) ... it work great
> until :
>
> Freeing unused kernel memory: 36k freed
> serial console detected. Disabling virtual terminals.
> console=/dev/ttyS0
>
> At this point the output of the serial line slow down dramaticly ... almost
> to a halt ... I get 1 line every 30 seconds !!!
>
> why is this slow down occuring ? the part which is 100% kernel is going fast
> and ok, but when it become console related ... it slows down ?

Serial just got its control signals (it is now *userland* writing, and
userland honours them), plus userland is probably opening/closing
serial all the time. Bad.
Pavel

-- 
Philips Velo 1: 1"x4"x8", 300gram, 60, 12MB, 40bogomips, linux, mutt,
details at http://atrey.karlin.mff.cuni.cz/~pavel/velo/index.html.

----- End forwarded message -----

-- 
--
I'm really pavel@atrey.karlin.mff.cuni.cz. 	   Pavel
Look at http://atrey.karlin.mff.cuni.cz/~pavel ;-).
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/