Where did the RAM go ..

David.Harding at brighthouse.co.uk David.Harding at brighthouse.co.uk
Tue Jun 29 05:18:54 CDT 2010


I think Mark was on to something when he spoke about memory reserved for 
PCI, and someone else mentioned DMA...
I think that it'll be something along those lines.
See the BIOS RAM Map when you boot a server, it'll look something like 
this:

Jun 29 09:02:58 sandpit kernel: BIOS-provided physical RAM map:
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 0000000000010000 - 
000000000009f800 (usable)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 000000000009f800 - 
00000000000a0000 (reserved)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 00000000000ca000 - 
00000000000cc000 (reserved)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 00000000000dc000 - 
0000000000100000 (reserved)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 0000000000100000 - 
000000007fef0000 (usable)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 000000007fef0000 - 000000
007feff000 (ACPI data)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 000000007feff000 - 
000000007ff00000 (ACPI NVS)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 000000007ff00000 - 
0000000080000000 (usable)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 00000000fec00000 - 
00000000fec10000 (reserved)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 00000000fee00000 - 
00000000fee01000 (reserved)
Jun 29 09:02:58 sandpit kernel:  BIOS-e820: 00000000fffe0000 - 
0000000100000000 (reserved)

I haven't done the sums, but could the missing MBs be in the address 
ranges not marked usable?

Cheers,
dave





"Nick Lunt" <nick.lunt at patech-solutions.com> 
Sent by: <linux-poweredge-bounces at dell.com>
29/06/2010 08:55

To
"Steve Tempest" <Steve.Tempest at gts.apn.com.au>
cc
<linux-poweredge at dell.com>
Subject
RE: Where did the RAM go ..






 
 
From: Steve Tempest [mailto:Steve.Tempest at gts.apn.com.au] 
Sent: 29 June 2010 08:41
To: Nick Lunt
Cc: linux-poweredge at dell.com
Subject: RE: Where did the RAM go ..
 
 
add up the kernel cod and reserved parts of the dmesg and at that to your 
125 ... does that come close to the physical?
Aha, that gives 134215811 KB or 127.998 GB so I guess that's where it's 
gone, thanks !
Anyone got any good reference on what the reserved, code, data and init 
memory areas are please ?


 


__________ Information from ESET NOD32 Antivirus, version of virus 
signature database 5235 (20100628) __________

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com_______________________________________________
Linux-PowerEdge mailing list
Linux-PowerEdge at dell.com
https://lists.us.dell.com/mailman/listinfo/linux-poweredge
Please read the FAQ at http://lists.us.dell.com/faq

<td class='Content'>
<br>
-------------------------------------------------------------------------------------------<br>
Caversham Finance Limited, registered in England No 0785922 Registered office:<br> 5 Hercules Way, Leavesden Park, Watford WD25 7GS
<br>
Caversham Trading Limited, registered in England No 05396147 Registered office:<br> 5 Hercules Way, Leavesden Park, Watford WD25 7GS
<br>
BrightHouse Limited, registered in England No 06073794 Registered office:<br> 5 Hercules Way, Leavesden Park, Watford WD25 7GS
</td>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.us.dell.com/pipermail/linux-poweredge/attachments/20100629/4f52b75c/attachment.htm 


More information about the Linux-PowerEdge mailing list