Re: Memory allocation in NUMA system

[Keir Fraser <keir.fraser@eu.citrix.com>]

On 25/7/08 04:34, "Yang, Xiaowei" <xiaowei.yang@intel.com> wrote:

> Let's say we have a 2-node system, with node0 and node1's memory range
> being 0-0xc0000000 (<4G) and 0x100000000-0x1c0000000 (>4G) respectively.
> In that case, node1's memory is always preferred for domain memory
> allocation, no matter which node the created domain is pinned to. It
> results in performance penalty.
> 
> One possible fix is to specify all range for the domain memory
> allocation, which means local memory is preferred. This change may be
> restricted only to the domain pinned to one node for less impact.
> 
> One side effect is that the DMA memory size may be smaller, which makes
> device domain unhappy. This can be addressed by reserving node0 to be
> used lastly.

Doesn't your solution amount to what we already do, for the 2-node example?
i.e., node0 would not be chosen until node1 is exhausted?

 -- Keir