cvs commit: src/sys/i386/i386 machdep.c src/sys/kern kern_mib.c src/sys/sys sysctl.h systm.h

[Scott Long]

Wes Peters wrote:
> On Monday 28 February 2005 01:42 pm, Wes Peters wrote:
> 
>>wes         2005-02-28 21:42:57 UTC
>>
>>  FreeBSD src repository
>>
>>  Modified files:
>>    sys/i386/i386        machdep.c
>>    sys/kern             kern_mib.c
>>    sys/sys              sysctl.h systm.h
>>  Log:
>>  Add a sysctl that records the amount of physical memory in the machine.
> 
> 
> In case you're wondering why anyone would want this, vs. the already
> existing hw.physmem, consider:
> 
>  hw.physmem: 526737408
>  hw.usermem: 509272064
>  hw.realmem: 535691264
> 
> The difference between 'realmem' and 'physmem' should always be the same for 
> a given device, unless BIOS settings have altered the memory map somehow.  
> We use this as a quick check to verify the BIOS settings haven't been 
> altered (at least enough to change the memory map).  You'd be astonished 
> how much the physmem setting can bounce around on supposedly identical 
> hardware.
> 

So how does this interact with the PCI memory hole at the upper end of 
the 4GB boundary?

Scott