On Fri, Oct 23, 2009 at 01:31:10PM +0200, Tobias Oetiker wrote:

Mel,

Today Mel Gorman wrote:

quoted

On Fri, Oct 23, 2009 at 02:36:53AM -0700, David Rientjes wrote:

quoted

On Fri, 23 Oct 2009, Mel Gorman wrote:

quoted

quoted

Hmm, is this really supposed to be added to __alloc_pages_high_priority()?
By the patch description I was expecting kswapd to be woken up
preemptively whenever the preferred zone is below ALLOC_WMARK_LOW and
we're known to have just allocated at a higher order, not just when
current was oom killed (when we should already be freeing a _lot_ of
memory soon) or is doing a higher order allocation during direct reclaim.

It was a somewhat arbitrary choice to have it trigger in the event high
priority allocations were happening frequently.

I don't quite understand, users of PF_MEMALLOC shouldn't be doing these
higher order allocations and if ALLOC_NO_WATERMARKS is by way of the oom
killer, we should be freeing a substantial amount of memory imminently
when it exits that waking up kswapd would be irrelevant.

I agree. I think it's highly unlikely this patch will make any
difference but I wanted to eliminate it as a possibility. Patch 3 and 4
were previously one patch that were tested together.

hi hi ... I have tested '3 only' this morning, and the allocation
problems started again ... so for me 3 alone does not work while
3+4 does.

Hi,

What was the outcome of 1+2?

-- 
Mel Gorman
Part-time Phd Student                          Linux Technology Center
University of Limerick                         IBM Dublin Software Lab