Messages in this thread | | | Date | Sun, 2 Dec 2007 16:59:13 -0800 | From | Arjan van de Ven <> | Subject | Re: [feature] automatically detect hung TASK_UNINTERRUPTIBLE tasks |
| |
On Mon, 3 Dec 2007 01:07:41 +0100 Andi Kleen <andi@firstfloor.org> wrote:
> > We really need to get better diagnostics for the > > bad-kernel-behavior-that-is-seen-as-bug cases. If we ever want to > > get to the scenario where we have a more or less robust measure of > > kernel quality (and we're not all that far off for several cases), > > one thing > > One measure to kernel quality is to recover well from IO errors > (like network problems or broken block devices)
yes. and this patch will flag cases that don't (yet) work well
> > This patch will likely work against that by breaking error paths.
it won't break error paths, it will at most put a warning in the log. It doesn't kill or otherwise damage the system or process.
> > > This patch is a step in the right direction there, by quite a > > lot. > > > > I really don't understand what your objection is to this patch... > > is it that an enterprise distro can't ship with it on? (Which is > > fine btw) > > Any distribution aimed at end users cannot ship with it on.
That's a pretty bold statement; assuming that the TASK_KILLABLE patch is in, I don't see the problem.
And even if a distro doesn't turn it on, I still don't see a problem; it's a diagnostics patch that people can turn on (even at runtime) if they see problems.
> Also in general I have my doubts that the false positive:real bug > ratio of this warning is well balanced.
I'll just have to disagree with you then; but both of us are making wild guesses. Only one way to get the real false positive percentage.
> Just consider the original > example of dead network servers. Even in my relatively small > home network that that is a quite common occurrence. This patch > will break that all by throwing random backtraces when this > happens.
1) with TASK_KILLABLE that shouldn't happen 2) how does "throwing a backtrace" "break" things?
-- If you want to reach me at my work email, use arjan@linux.intel.com For development, discussion and tips for power savings, visit http://www.lesswatts.org
| |