i386 with 4GB RAM: less than 2GB available on A2SAV (Intel Atom E3940)

[Andre Albsmeier]

On Sun, 28-Jan-2018 at 22:51:04 +0700, Eugene Grosbein wrote:
> 28.01.2018 21:57, Andre Albsmeier wrote:
> 
> > I have a lot of machines running with 4 GB physical RAM and, for
> > some reasons, I still have to use a 32 bits OS.
> > 
> > All of them show something between 3 and 3.5 GB of RAM available
> > in dmesg but the brand new Supermicro A2SAV really shocked me:
> > 
> > FreeBSD 11.1-STABLE #0: Mon Jan 15 06:57:10 CET 2018
> > ...
> > real memory  = 4294967296 (4096 MB)
> > avail memory = 1939558400 (1849 MB)
> > ...
> > 
> > So do people have any ideas how I might get a bit closer to at least
> > 3 GB? I assume there are no FreeBSD knobs which might help but hope
> > dies last...
> 
> First, try to decrease amount of RAM dedicated to integrated video, if any (BIOS Setup).

Done that. I have set everything as small as possible but this didn't help.
After a BIOS upgrade, I found the promising option

MAX TOLUD

which was set to 2GB. I changed it to 3GB but nothing changed.

> 
> Also, I'd like to know reasons that made you stick to 32 bit OS
> as we have pretty good support for 32 bit applications running under 64 bit system.

I (still) have 32 bit machines and don't want to maintain 2 userlands.
Each machine has its own kernel but userland (updated via nfs) must
remain 32 bit.

Or is it possible to boot a 64 bit kernel and have everything else in
32 bit?