solaris 9 x86 memory limit?

[Swany]

I have a box with 4GB of ram (4 1GB dimms).
prtconf reports only 3.5 gigs of memory (as do vmstat, top, etc)..

How can I make the box see all 4GB of memory?

[George Fitzpatrick]

Post by Swany
I have a box with 4GB of ram (4 1GB dimms).
prtconf reports only 3.5 gigs of memory (as do vmstat, top, etc)..
How can I make the box see all 4GB of memory?

I think what you're seeing is the result of a machine with a PCI bus
reserving the memory addresses in the 3.5 to 4.0 GB range for itself. If
I recall correctly, I saw this in a technote on the Tyan website when I
was researching an S2466 motherboard. Don't know if there's a
work-around ...

[Barry OGrady]

Post by Swany
I have a box with 4GB of ram (4 1GB dimms).
prtconf reports only 3.5 gigs of memory (as do vmstat, top, etc)..
How can I make the box see all 4GB of memory?

If you were running Windows 2003 you could use PAE.
Its a 32 bit addressing limitation.

=-=-=
Barry
http://members.iinet.net.au/~barry.og

[Andrew Gabriel]

Post by Barry OGrady

Post by Swany
I have a box with 4GB of ram (4 1GB dimms).
prtconf reports only 3.5 gigs of memory (as do vmstat, top, etc)..
How can I make the box see all 4GB of memory?

If you were running Windows 2003 you could use PAE.
Its a 32 bit addressing limitation.

Solaris supports PAE since Solaris 7.

When you see 3.5GB of memory when there's 4GB fitted, it's
due to addressing limits in the motherboard chipset, whereby
it can only address 4GB max, but out of that has to be taken
all memory mapped i/o, such as the PCI mapping areas, reducing
you to something less than 4GB of memory being addressable.

Also, some video cards steal main system memory - not sure how
that shows up in practice.

[Benjamin Gawert]

Post by Andrew Gabriel
Solaris supports PAE since Solaris 7.
When you see 3.5GB of memory when there's 4GB fitted, it's
due to addressing limits in the motherboard chipset,

Chipset and BIOS. Both need to explicitly support PAE which for single
processor desktop PCs rarely is the case.

Post by Andrew Gabriel
whereby
it can only address 4GB max, but out of that has to be taken
all memory mapped i/o, such as the PCI mapping areas, reducing
you to something less than 4GB of memory being addressable.
Also, some video cards steal main system memory - not sure how
that shows up in practice.

All video cards do that. The video memory is directly mapped into the
I/O area.

Benjamin

[Andrew Gabriel]

Post by Benjamin Gawert

Post by Andrew Gabriel
Solaris supports PAE since Solaris 7.
When you see 3.5GB of memory when there's 4GB fitted, it's
due to addressing limits in the motherboard chipset,

Chipset and BIOS. Both need to explicitly support PAE which for single
processor desktop PCs rarely is the case.

Post by Andrew Gabriel
whereby
it can only address 4GB max, but out of that has to be taken
all memory mapped i/o, such as the PCI mapping areas, reducing
you to something less than 4GB of memory being addressable.
Also, some video cards steal main system memory - not sure how
that shows up in practice.

All video cards do that. The video memory is directly mapped into the
I/O area.

Yes, that's covered by the PCI mappings above.
However, here I'm refering to GPUs which actually use some of the
system's main (motherboard) memory too (not just virtual memory
address space).

[Canuck57]

Post by Barry OGrady

Post by Swany
I have a box with 4GB of ram (4 1GB dimms).
prtconf reports only 3.5 gigs of memory (as do vmstat, top, etc)..
How can I make the box see all 4GB of memory?

If you were running Windows 2003 you could use PAE.
Its a 32 bit addressing limitation.
=-=-=
Barry
http://members.iinet.net.au/~barry.og

Should he not be able to run the 64 bit kernal? Assuming his processor
is 64 bit, which it may very well not be.