[Crash-utility] spanned vs. present

[Dave Anderson]

----- "Per Fransson" <per.fransson.ml at gmail.com> wrote:

> Hi,
> 
> I'm wondering why kmem -f uses the spanned pages of every zone when
> reporting its size. Wouldn't it be more informative to get a value
> which excludes any holes?
> 
> This is the code from memory.c I'm thinking of:
> 
> /*
>  *  Same as dump_free_pages_zones_v1(), but updated for numerous 2.6 zone
>  *  and free_area related data structure changes.
>  */
> static void
> dump_free_pages_zones_v2(struct meminfo *fi)
> {
> 	[...]
> 	if (VALID_MEMBER(zone_spanned_pages))
> 		zone_size_offset =  OFFSET(zone_spanned_pages);
> 	else
> 		error(FATAL, "zone struct has no spanned_pages field\n");
> 	[...]
> }

You can get the present pages with "kmem -z".

Dave