Re: DEBUG_PAGEALLOC & SMP?

Ingo Molnar
2005-06-23T11:13:42Z

* Ingo Molnar <mingo@elte.hu> wrote:

> > full log attached below. (ob'fun: the oom-killer picked the migration
> > thread to kill ;)
>
> this was with the -RT tree - let me try whether the same happens on
> vanilla 2.6.12 too.

[ 1 hour later ... ] the mystery is solved: i had a ~15 MB kernel image
size due to various debugging options plus per-CPU tracing buffer at
NR_CPUS=8. PAGEALLOC caused an extra +1MB of DMA-zone kernel footprint
(the 4k granular kernel pagetables of 1 GB physical RAM), which was the
final drop and depleted the DMA pool completely.

Ingo