5.4-RC2 freezing - ATA related?

[Elliot Finley]

> On Mon, May 16, 2005 at 06:40:01AM -0600, Elliot Finley wrote:
> >The system freezes, but isn't totally dead.  It'll still respond to
pings,
> >the screensaver still functions, but it won't respond to a CAD at the
> >console.  But if I press 'Enter' at the console, it'll give me a 'login:'
> >prompt, but after entering the username, it never comes back with the
> >'password:' prompt.
> ...
> >On my lightly loaded systems, it happens rarely.  On my mailserver
(fairly
> >heavy disk load), it happens quite frequently.
>
> This could equally be a filesystem deadlock (race-to-root) rather than
> something in the ATA controller.  Do you know if it happens gradually
> (starts with one or two non-responsive, unkillable processes and gets
> worse until nothing happens)?
>
> >How can I troubleshoot this?
>
> Re-compile the kernel with:
>    options KDB
>    options DDB
>    makeoptions DEBUG=-g
> and ensure you have a "dumpdev" in /etc/rc.conf.  When you get a
> lockup, drop to DDB (Ctrl-Alt-ESC) and run "show lockedvnods", "ps"
> and "call doadump()".  If you post the output (a serial console will
> help here) someone might be able to provide more pointers.  (The
> crashdump will help with later debugging).

Had the system lock up again.  This is with the new ATA mkIII patches on
http://people.freebsd.org/~sos/ATA.

I didn't get the crashdump (forgot to set dumpdev), but I did get 'ps' and
'show lockedvnods' output from DDB.  The output is in the form of
screenshots combined into a single .pdf which can be accessed here
http://www.efinley.com/Binder1.pdf

I hope this is helpful, I'll get a crashdump next time (probably tomorrow
morning).

Elliot