avail memory is short by 1G on my FreeBSD 6.0-STABLE MP Dell

[Chad Leigh -- Shire.Net LLC]

On Nov 21, 2005, at 10:05 AM, Daniel Rock wrote:

> Chad Leigh -- Shire.Net LLC schrieb:
>> I assume you are talking about the "phenomenon"  of RAM "missing"  
>> due  to PCI and other I/O mapping into the 4GB address space?   
>> What struck  me about the OP is that the amount of RAM "missing"  
>> is more than I  have ever seen due to this.  My systems are  
>> usually 3.4-3.6GB of RAM  with 4GB installed, not 2.86GB  
>> (3005MB)...  So are we sure that the  PCI space mapping is the  
>> problem?
>
> This is nothing unusual. I have a machine on which over 1.25GB is  
> mapped "out of the way". It is a Tyan Thunder K8WE (S2895). In BIOS  
> I can choose between Hardware/Software/Disabled mapping:
>
>
> Hardware (requires E-stepping CPUs):
> real memory  = 5637144576 (5376 MB)
> Physical memory chunk(s):
> 0x0000000000001000 - 0x0000000000090fff, 589824 bytes (144 pages)
> 0x0000000000985000 - 0x00000000a616ffff, 2776543232 bytes (677867  
> pages)
> 0x0000000100000000 - 0x000000014ffdffff, 1342046208 bytes (327648  
> pages)
> avail memory = 4109500416 (3919 MB)
>
> Software (should work regardless of stepping):
> real memory  = 6442450944 (6144 MB)
> Physical memory chunk(s):
> 0x0000000000001000 - 0x0000000000090fff, 589824 bytes (144 pages)
> 0x0000000000985000 - 0x000000007ff1ffff, 2136584192 bytes (521627  
> pages)
> 0x0000000100000000 - 0x0000000174baffff, 1958412288 bytes (478128  
> pages)
> avail memory = 4085907456 (3896 MB)
>
> Disabled:
> real memory  = 2951872512 (2815 MB)
> Physical memory chunk(s):
> 0x0000000000001000 - 0x0000000000090fff, 589824 bytes (144 pages)
> 0x0000000000983000 - 0x00000000aac56fff, 2855092224 bytes (697044  
> pages)
> avail memory = 2846003200 (2714 MB)

Yes, but in your case the real memory is > 4gb so of course the  
amount mapped would be less.  I have never seen on any of my  
motherboards, > 1Gb getting mapped when the physical memory is only 4GB

Chad


>
>
>
> Daniel

---
Chad Leigh -- Shire.Net LLC
Your Web App and Email hosting provider
chad at shire.net