PAE does not give any ram increase, why?

[Artem Kuchin]

Andrew Pantyukhin wrote:
> On 4/21/07, Artem Kuchin <matrix at itlegion.ru> wrote:
>> Hello!
>> 
>> I've upgraded one of my servers today.
>> Now it is
>> Asus P5p800-VM
>> Pentium D 3.0Ghz
>> 4GB RAM (4x1 GB)
>> 3WARE raid5
>> 
>> FreebSD 6.2 cvsed today compiled from sources.
>> 
>> after that i decided to try PAE. It runs just fine but
>> when i compare available memory with and without
>> pae i do not see any difference.
>> 
>> At kernel boot with PAE it says:
>> 
>> pr 21 18:01:30 osiris kernel: ACPI APIC Table: <A M I  OEMAPIC >
>> Apr 21 18:01:30 osiris kernel: Timecounter "i8254" frequency 1193182
>> Hz quality 0 
>> Apr 21 18:01:30 osiris kernel: CPU: Intel(R) Pentium(R) D CPU
>> 3.00GHz (3000.33-MHz 686-class CPU) Apr 21 18:01:30 osiris kernel:
>> Origin = "GenuineIntel"  Id = 0xf64  Stepping = 4 
>> Apr 21 18:01:30 osiris kernel:
>> Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2
>> Apr 21 18:01:30 osiris kernel:
>> Features2=0xe49d<SSE3,RSVD2,MON,DS_CPL,EST,CNTX-ID,CX16,<b14>,<b15>>
>> Apr 21 18:01:30 osiris kernel: AMD Features=0x20000000<LM> 
>> Apr 21 18:01:30 osiris kernel: AMD Features2=0x1<LAHF>
>> Apr 21 18:01:30 osiris kernel: Cores per package: 2
>> Apr 21 18:01:30 osiris kernel: real memory  = 4017881088 (3831 MB)
>> Apr 21 18:01:30 osiris kernel: avail memory = 3933429760 (3751 MB)
>> 
>> The real and avail memory sizes are the same w/o PAE.
>> 
>> Then i do
>> sysctl -a | grep hw | grep mem
>> 
>> and i always see
>> hw.physmem: 4012244992
>> hw.usermem: 3861307392
>> hw.realmem: 4017881088
>> hw.pci.host_mem_start: 2147483648
>> 
>> the number do not change with or without PAE
>> 
>> Maybe i look in the wrong place?
> 
> What number do you expect to see? 8Gb?

I expect to see DIFFERENCE (in particular INCREASE) in amount of memory with PAE
comparing to kernel w/o PAE. 

And 4 GB = 1024*4 MB = 1024*1024*4 KB = 
= 1024*1024*1024*4=4294967296

So, where is my 277086208 bytes?
(ieven is built-in video eats 128MB for AGP aperture then still
whene is my another almost 120MB?)

--
Regards,
Artem