On Thu, 18 Aug 2011, Américo Wang wrote:
On Thu, Aug 18, 2011 at 6:51 PM, Justin Piszcz <jpiszcz@xxxxxxxxxxxxxxx> wrote:
Hi,
I have a SuperMicro X8DTH-6F motherboard with 2 cpus it has NUMA options in
the BIOS; what parameters/should I be using for the NUMA options in the
kernel?
| | [*] Numa Memory Allocation and Scheduler Support | |
| | [ ] Old style AMD Opteron NUMA detection | |
| | [*] ACPI NUMA detection | |
| | [ ] NUMA emulation | |
| | (6) Maximum NUMA Nodes (as a power of 2) | |
That is Intel processor, right? If so, the things you selected here are enough,
Hi, yes-- two Intel Xeon E5645s.
the rest two is not what you need.
Ok.
Specifically, the maximum number of NUMA nodes? Will this help to increase
performance of large memory allocations/is there any downside
to enabling this feature?
The max of NUMA nodes is specified by CONFIG_NODES_SHIFT,
in your case, it is 6, which means it supports up to 2^6 nodes.
Ok, is there any overhead having more than is needed?
If your hardware supports NUMA, yes, that certainly help to increase
the performance.
Nice, thanks.
Justin.
