Re: Linux Kernel Dump Summit 2005

Theodore Ts'o
2005-10-19T19:00:50Z

On Tue, Oct 18, 2005 at 03:10:24PM +0100, Hugh Dickins wrote:
> On Tue, 18 Oct 2005, OBATA Noboru wrote:
> >
> > I have a bitter experience in analyzing a partial dump. The
> > dump completely lacks the PTE pages of user processes and I had
> > to give up analysis then. A partial dump has a risk of failure
> > in analysis.
>
> Page tables of user processes are very often essential in a dump.
> Data pages of user processes are almost always just a waste of
> space and time in a dump. Please don't judge against partial
> dumps on the basis of one that was badly selected.

We've had hard-to-reproduce problems out in the field where being able
to find the data pages of the user process was critical to figuring
out what the heck was going on. So I wouldn't be quite so eager to
dismiss the need for user pages. There are times when they come in
quite handy....

- Ted