random FreeBSD panics

[Gary Jennejohn]

On Sat, 3 Apr 2010 12:51:46 +0000
Masoom Shaikh <masoom.shaikh at gmail.com> wrote:

> On Sun, Mar 28, 2010 at 5:38 PM, Ivan Voras <ivoras at freebsd.org> wrote:
> > On 28 March 2010 16:42, Masoom Shaikh <masoom.shaikh at gmail.com> wrote:
> >
> >> lets assume if this is h/w problem, then how can other OSes overcome
> >> this ? is there a way to make FreeBSD ignore this as well, let it
> >> result in reasonable performance penalty.
> >
> > Very probably, if only we could detect where the problem is.
> > Try adding "options __ __ PRINTF_BUFR_SIZE=128" to the kernel
> > configuration file if you can, to see if you can get a less mangled
> > log outout.
> >
> 
> ok, after few days of silence I am back with more questions
> this time system feels little better, it is able to sustain for more
> time that what 7.3-RELEASE could
> 
> FreeBSD raptor 8.0-RELEASE-p2 FreeBSD 8.0-RELEASE-p2 #0: Thu Apr  1
> 01:20:45 UTC 2010     root@:/usr/obj/usr/src/sys/INSPIRON  amd64
> 
> I am using KDE4, and when OS freezes, well it freezes, means I cannot
> change to tty0 and see the panic text, if any it might possibly have
> spit. the stuck frozen GUI keeps staring there. So the question is how
> to I capture that panic text ? unfortunately I am not getting core
> files too, so there is nothing I can pick up hints
> 
> is there some option (KDB, DDB), so that on panic system drop to debugger ?
> 

[trimmed Cc - no need to send this to 3 MLs]

There's no code in the kernel to switch back out of graphics mode (i.e.
what X uses) when a panic happens.

You probably can switch to v0, but you won't be able to see it.

The only sure-fire way is to hook up a screen (terminal, laptop or
another computer) to a serial port.

--
Gary Jennejohn