Can I get the NUMA node from a pointer address (in C on Linux)?

Question

I\'ve set up my code to carefully load and process data locally on my NUMA system. I think. That is, for debugging purposes I\'d really like to be able to use the pointer

Answer 1

Alternatively, there is a get_mempolicy function in -lnuma: http://linux.die.net/man/2/get_mempolicy

If flags specifies both MPOL_F_NODE and MPOL_F_ADDR, get_mempolicy() will 
return the node ID of the node on which the address addr is allocated into 
the location pointed to by mode. If no page has yet been allocated for the 
specified address, get_mempolicy() will allocate a page as if the process had 
performed a read [load] access to that address, and return the ID of the node 
where that page was allocated. 

Thus, the numa node of a page being pointed at by ptr is checked with:

int numa_node = -1;
get_mempolicy(&numa_node, NULL, 0, (void*)ptr, MPOL_F_NODE | MPOL_F_ADDR);
return numa_node;