Re: make swappiness safer to use

[Fengguang Wu <fengguang.wu@gmail.com>]

On Wed, Aug 01, 2007 at 09:19:25AM +0800, Fengguang Wu wrote:
> > +		imbalance *= (vm_swappiness + 1) / 100;
>                              ~~~~~~~~~~~~~~~~~~~~~~~~~ It will be zero!
> 
> Better to scale it up before the division:
> 		imbalance *= (vm_swappiness + 1) * 1024 / 100;
> 
> > +
> > +		/*
> > +		 * If not much of the ram is mapped, makes the imbalance
> > +		 * less relevant, it's high priority we refill the inactive
> > +		 * list with mapped pages only in presence of high ratio of
> > +		 * mapped pages.
> > +		 *
> > +		 * Max temporary value is vm_total_pages*100.
> > +		 */
> > +		imbalance *= mapped_ratio / 100;
> 
> 		imbalance *= mapped_ratio * 1024 / 100;
> 
> > +		/* apply imbalance feedback to swap_tendency */
> > +		swap_tendency += imbalance;
> 
> 		swap_tendency += imbalance / 1024 / 1024;

Or simply move the two ' / 100' to this last line?

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>