topic Numa Nodes & Package Information in Software Tuning, Performance Optimization & Platform Monitoring

Numa Nodes & Package Information

robchip — Thu, 19 Apr 2012 09:57:07 GMT

Hello everyone

I'm trying to detect the NUMA nodes on a system, but I'm a bit confused with the terminology used by Intel:

With the CPUID command I can get package information, etc: Is a NUMA node the same as a package?

Or does a package refer to the CPU socket (which I guess on most NUMA systems would be the same as a NUMA node)?

Thanks in advance for clearing it up!
Robert

Edit: I'd like to do the whole thing without using a library since the program doesn't run on linux/windows/etc. (research OS).

Numa Nodes & Package Information

Thomas_W_Intel — Thu, 19 Apr 2012 10:51:24 GMT

NUMA nodes are provided to the operating systemby the System Resource Affinity Table (SRAT) in the Advanced Configuration and Power Interface (ACPI). From user space, the easiest solution is to rely on libraries like libnumaon Linux or the Windows NUMA interface.

Numa Nodes & Package Information

robchip — Thu, 19 Apr 2012 11:06:03 GMT

Thank's - I'll look into the document.
Unfortunately the program runs on a research OS - therefore I'd like to do the things without a library (sorry forgot it in the original post)

Numa Nodes & Package Information

Thomas_W_Intel — Thu, 19 Apr 2012 12:06:03 GMT

Only after posting my reply, I remembered that you stated in some other thread that you are working on an OS. :(

The document contains other useful information for OS writers, e.g. about initializingprocessors.

The linkstothe librariesmight be useful for otherswho come across the thread and are not writing an OS :).

Numa Nodes & Package Information

TimP — Thu, 19 Apr 2012 13:05:42 GMT

When I've seen the term package used, it's equivalent to a CPU socket. There's lots of dissension over whether "CPU" means core or package.
Could you port the open source hwloc (from OpenMPI)?