FYI: 2.6.16-smp: DMA memory inbalance for NUMA?

["Ulrich Windl" <ulrich.windl@rz.uni-regensburg.de>]

Hi,

my apologies if this is an issue already solved:
I have no idea what these messages exactly say, but for reasons of symmetry I 
think there's something wrong:
For a Sun Fire X4100 with two Dual_Core Operon processors, the kernel (SLES10 
kernel (x86_64, 2.6.16.21-0.15-smp)) says during boot:

<6>SRAT: PXM 0 -> APIC 0 -> Node 0
<6>SRAT: PXM 0 -> APIC 1 -> Node 0
<6>SRAT: PXM 1 -> APIC 2 -> Node 1
<6>SRAT: PXM 1 -> APIC 3 -> Node 1
<6>SRAT: Node 0 PXM 0 100000-f4000000
<6>SRAT: Node 1 PXM 1 20c000000-40c000000
<6>SRAT: Node 0 PXM 0 100000-20c000000
<6>SRAT: Node 0 PXM 0 0-20c000000

[[ Note: "Node 0" is mentioned three times, but "Node 1" is only mentioned once. 
If this is intended to be some address assignments, they look quite odd to me. 
Does the following really mean that only one node can do DMA (the other has zero 
DMA pages)? ]]

<6>ACPI: SLIT table looks invalid. Not used.
<7>NUMA: Using 26 for the hash shift.
<6>Bootmem setup node 0 0000000000000000-000000020c000000
<6>Bootmem setup node 1 000000020c000000-000000040c000000
<7>On node 0 totalpages: 2066745
<7>  DMA zone: 2993 pages, LIFO batch:0
<7>  DMA32 zone: 981032 pages, LIFO batch:31
<7>  Normal zone: 1082720 pages, LIFO batch:31
<7>  HighMem zone: 0 pages, LIFO batch:0
<7>On node 1 totalpages: 2068480
<7>  DMA zone: 0 pages, LIFO batch:0
<7>  DMA32 zone: 0 pages, LIFO batch:0
<7>  Normal zone: 2068480 pages, LIFO batch:31
<7>  HighMem zone: 0 pages, LIFO batch:0

As usual, please CC: replies to my address as I'm not subscribed here.

Regards,
Ulrich

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/