Real and availible RAM

Eric Anderson anderson at
Tue May 6 05:58:20 PDT 2003

Terry Lambert wrote:
> Eric Anderson wrote:
>>>If you look at the way x86 architecture is designed (and somebody else can
>>>feel free to correct me if I'm wrong), but system memory is often used in
>>>the caching/shadowing of BIOS. This is where a lot of system memory often
>>>goes before the OS is loaded - also, as Rob said, the kernel itself will
>>>take up memory before the rest of the OS is booted.
>>I believe that the BIOS steals the ram prior to the OS booting, so that
>>the box does not show that as part of the total ram.. Like:
> Since the BIOS is where FreeBSD obtains the "real memory" number,
> this is pretty unlikely; the BIOS would just lie to FreeBSD about
> the number, and be done with it.
[..snipped the blabla..]

I think you missed my point - I wasn't saying that FreeBSD is hiding 
anything, nor was I talking about the "missing 6mb problem" directly. 
You pretty much repeated my point though - "Since the BIOS is where 
FreeBSD obtains the "real memory" number" - which is what I said, that 
the BIOS takes the physical RAM, subtracts what it needs for devices 
like video cards (that "borrow" from physical main memory), then reports 
that result to any OS/Apps/etc that ask for it.  That is why my system 
doesn't show the 256Mb of memory it has in it, it shows something like 
224Mb (32Mb is set aside for the video card)..

Unless I am totally missing your point this morning.. :)


Eric Anderson	   Systems Administrator      Centaur Technology
Attitudes are contagious, is yours worth catching?

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