excessive kworker activity when idle. (was Re: vma corruption in today's -git)

Dave Jones
2011-03-31T03:09:27Z

On Mon, Mar 28, 2011 at 09:22:25PM -0700, Linus Torvalds wrote:
> On Mon, Mar 28, 2011 at 9:09 PM, Dave Jones <davej@redhat.com> wrote:
> >
> > I ran perf top, and got this ..
> >
> >  BUG: unable to handle kernel paging request at fffffffffffffff3
>
> Should be fixed by commit 76597cd31470.
>
> Except that was already committed yesterday. When did you pull?

It did fix it, I must have missed that commit.

But rerunning the same tests on current head (6aba74f2791287ec407e0f92487a725a25908067)
I can still reproduce the problem where kworker threads go nutso
when the machine should be completely idle.

top shows two kworker threads constantly at >80% cpu.

I can now profile it with perf though, so I'll dig deeper.
I need to try a build with slab debug etc turned off, just to be sure that
isn't throwing things into a spin.

Dave