At 02:48 PM 8/24/2007, Peter Schuller wrote:
Hello,

I have a Dell 2950 where my 7-CURRENT amd64 FreeBSD does not see all visible
memory. It has 4 GB of physical RAM. dmesg on boot includes:

usable memory = 4280811520 (4082 MB)
avail memory  = 4117716992 (3926 MB)

Yet summing memories visible in top yields ~ 2100 MB.

Of note is that I have 6.2/amd64 on several other 2950:s with 4GB of RAM which
say on boot:

real memory  = 5100273664 (4864 MB)
avail memory = 4122443776 (3931 MB)

But has all 4 GB visible in top.

Unfortunately I failed to notice this until after the machine has begun being
used, so I have limited possibilities for rebooting/mucking with BIOS
settings. I was hoping someone could suggest something right off the bat.

In addition on the problem machine the following sysctl values are present:

hw.physmem: 4280811520
hw.usermem: 3628220416
hw.realmem: 5100273664
hw.cbb.start_memory: 2281701376
hw.pci.host_mem_start: 2147483648

With hw.usermem being slightly higher (but not 2 GB higher) on the 6.2 system
without a problem:

hw.physmem: 4283285504
hw.usermem: 3998797824
hw.realmem: 5100273664
hw.cbb.start_memory: 2281701376
hw.pci.host_mem_start: 2147483648

I was under the impression that memory visibility issues were a thing of the
past on amd64. Any insight?

Thanks!

--
/ Peter Schuller

You need to look closely at the hardware configuration for these servers and their motherboards. Often some memory is reserved for things like onboard video, etc. You can free up that video memory by adding a separate video card, but necessarily other memory that may be used by the motherboard. Unfortunately with dell systems same model's don't necessarily mean same motherboard. Also, how memory is used via the BIOS is dependent on the BIOS version. You should try to be sure all systems you want to compare have the same motherboard and chipset and that these also have the same BIOS version.

        -Derek



PGP userID: 0xE9758B7D or 'Peter Schuller <[EMAIL PROTECTED]>'
Key retrieval: Send an E-Mail to [EMAIL PROTECTED]
E-Mail: [EMAIL PROTECTED] Web: http://www.scode.org

_______________________________________________
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "[EMAIL PROTECTED]"

--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
MailScanner thanks transtec Computers for their support.

--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
MailScanner thanks transtec Computers for their support.

_______________________________________________
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "[EMAIL PROTECTED]"

Reply via email to