too many holes in address space, memory ignored

[Scott Long]

Don Bowman wrote:
> On my 4GB system with PAE disabled, i'm getting these
> two messages out on boot:
>  262144K of memory above 4GB ignored
>  Too many holes in the physical address space, giving up
> 
> I'm assuming the first one is due to the address
> space needing locations for memory mapped io like
> PCI, so some ram is wasted.

Actually, it's the opposite.  The northbridge is remapping
the memory that is normally hidden by the PCI window so that it
doesn't get wasted.

> The second... this comes from sys/i386/i386/machdep.c
> Is there any reason i wouldn't just increase
> 'vm_paddr_t phys_avail[10];' to a number > 10?
> (and/or increase PHYSMAP_SIZE?)
> 

Can't comment on the safety of that, other than to wonder if you have a
the BIOS set to shadow a bunch of <1MB segments.

Scott