Real and availible RAM

Eric Anderson anderson at
Tue May 6 08:14:06 PDT 2003

Terry Lambert wrote:
> Eric Anderson wrote:
>>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.. :)
> You are.  The video memory you are talking about in this case is
> accounted for by the AGP or a similar video driver.  It is not
> sucked up by the BIOS.  At most, the BIOS will "eat" a few K
> (usually, no more than 4K) that is unknown to the OS.

Ahh.. right you are.. thanks for the correction..

> Again, you really need to read the machdep.c code, particularly
> the "memsize()" function.

Yep - I see now.. thanks for the pointer (again).


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

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