Re: was: CURRENT [r308087] still crashing: Backtrace provided

Am Sun, 23 Oct 2016 15:18:57 -0400 (EDT)
Benjamin Kaduk <kaduk_at_MIT.EDU> schrieb:

> On Sun, 23 Oct 2016, O. Hartmann wrote:
> 
> > How can I track a memory leak?  
> 
> I think I did not read enough of the context, but vmstat and top can track
> memory usage as a general thing.
> 
> > How can I write to disk the backtrace given by the debugger when
> > crashing? My box I can freely test is using the nVidia BLOB and vt(), so
> > I can not see the backtrace. I got a very bad screenshot on one of my
> > laptops, but its so ugly/unreadable, I think it is unsuable to be
> > presented within this list at a reasonable size (200 kB max ist too
> > small).  
> 
> The backtrace should be part of the crash dump that is written to the
> (directly connected, non-encrypted, non-USB) swap device.  "call doadump"
> at the debugger prompt (even typing blind) is supposed to make sure
> there's a dump taken.
> 
> With respect to the screenshot, you should be able to post the image on an
> external site and send a link to the list, at least.
> 
> -Ben
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Hello Benjamin,

thank you for your response. Attached, you'll find the backtrace developers seem
to have requested for. It was a bit hard, since FreeBSD, vt() and nVidia is broken
(black or distorted console, on UEFI it is black/locked as long as the nvidia-modeset,ko
module is loaded). I figured out that I could blindly type "dump" when the box has
crashed and resided at the debugger promt.

I hope this time I could provide the help to fix this really nasty problem. On more
recent hardware, Haswell and beyond, I was able to run CURRENT even with ZFS and
poudriere on a hard memory pressure without crash within three days. On older machines,
one older Fujitsu dual socket Core2Duo XEON (2x 4 core, 2x 16 GB RAM banks) as well as
two of my private boxes (1x IvyBridge XEON, one   i3-3220, both wit a non-UEFI-working
ASROCK Z77 Pro4 board) crash, if FreeBSD is > r307157. Staying on those systems with
r307157 leaves the machine "rock-solid" - the XEON box last now for a week uptime. 

Since the only box I can more or less freely test with is the slowest of all, the
i3-3220. So it takes a while until I have recompiled a world.

Thanks you very much in advance,

Oliver