Re: [PATCH 8/8] Add VM counters for transparent hugepages

[KOSAKI Motohiro]

> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> 
> I found it difficult to make sense of transparent huge pages without
> having any counters for its actions. Add some counters to vmstat
> for allocation of transparent hugepages and fallback to smaller
> pages.
> 
> Optional patch, but useful for development and understanding the system.
> 
> Contains improvements from Andrea Arcangeli and Johannes Weiner
> 
> Acked-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
> Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
> ---
>  include/linux/vmstat.h |    7 +++++++
>  mm/huge_memory.c       |   25 +++++++++++++++++++++----
>  mm/vmstat.c            |    8 ++++++++
>  3 files changed, 36 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
> index 9b5c63d..074e8fd 100644
> --- a/include/linux/vmstat.h
> +++ b/include/linux/vmstat.h
> @@ -58,6 +58,13 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
>  		UNEVICTABLE_PGCLEARED,	/* on COW, page truncate */
>  		UNEVICTABLE_PGSTRANDED,	/* unable to isolate on unlock */
>  		UNEVICTABLE_MLOCKFREED,
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +	        THP_FAULT_ALLOC,
> +		THP_FAULT_FALLBACK,
> +		THP_COLLAPSE_ALLOC,
> +		THP_COLLAPSE_ALLOC_FAILED,
> +		THP_SPLIT,
> +#endif
>  		NR_VM_EVENT_ITEMS
>  };

Hmm...
Don't we need to make per zone stastics? I'm afraid small dma zone 
makes much thp-splitting and screw up this stastics.

only nit.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/