Re: swsusp: how much memory to free? [was Re: swsusp performance problems in 2.6.15-rc3-mm1]

[Pavel Machek <pavel@suse.cz>]

Hi!

> > > OTOH, we can get similar result by just making the kernel free some
> > > more memory _after_ we are sure we have enough memory to suspend.
> > > IOW, after the code that's currently in swsusp_shrink_memory() has finished,
> > > we can try to free some "extra" memory to improve performance, if
> > > needed.  The question is how much "extra" memory should be freed and
> > > I'm afraid it will have to be tuned on the per-system, or at least
> > > per-RAM-size, basis.
> > 
> > I'd prefer not to have extra tunables. "Write only 500MB" will work
> > okay for common desktop users -- as long as common desktop fits into
> > 500MB, that is. "Free not used in last 10 minutes" should work okay
> > for everyone, but may be slightly harder to implement.
> 
> Still, it can be done with a fairly small patch that has an additional
> advantage, as it allows us to get rid of the FAST_FREE constant
> which I don't like.  Appended (untested).

Looks good to me.

> Index: linux-2.6.15-rc5-mm1/kernel/power/swsusp.c
> ===================================================================
> --- linux-2.6.15-rc5-mm1.orig/kernel/power/swsusp.c	2005-12-05 22:07:12.000000000 +0100
> +++ linux-2.6.15-rc5-mm1/kernel/power/swsusp.c	2005-12-07 12:40:27.000000000 +0100
> @@ -626,6 +626,7 @@
>  
>  int swsusp_shrink_memory(void)
>  {
> +	unsigned long size;
>  	long tmp;

Perhaps both should be long, or both unsigned long?

								Pavel
-- 
Thanks, Sharp!