5.3-RELEASE on Dell PowerEdge 2850

Dan Nelson dnelson at allantgroup.com
Wed Oct 27 08:23:16 PDT 2004


In the last episode (Oct 27), Tom Gidden said:
> I've recently got a few Dell PowerEdge 2850 machines with 4 GB RAM to
> build a new database cluster.  However, unlike our existing PowerEdge
> 2650 machines, they're only recognising about 3.25 GB.  The machines
> are pretty much standard, with no extra cards (just the built-in
> MegaRAID).
> 
> As a last resort, I've tried rebuilding the kernel with
> MAXMEM=(4*1024*1024), which produces some really fun crashes (which I
> can supply if necessary).  The BIOS seems to be devoid of anything
> remotely useful to tweak.
> 
> Any ideas?
> 
> Here's a dmesg from the non-crashing kernel:  [note, the first line
> is from memory and might be incorrect]
> 
> 786426K of memory above 4GB ignored

It looks like you will need to enable PAE to access the rest of that
memory (see the pae manpage; some hardware will not work with it
enabled).  Dell has apparently put quite a bit of your memory past the
4GB point, and left a 700MB hole somewhere in lower memory.  I think if
you do a boot -v, it will print the memory ranges.

-- 
	Dan Nelson
	dnelson at allantgroup.com


More information about the freebsd-questions mailing list