Hi Peter, Sorry if this has already been reported, but On Fri, Mar 16, 2012 at 7:40 AM, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote: > > Hi All, > > While the current scheduler has knowledge of the machine topology, including > NUMA (although there's room for improvement there as well [1]), it is > completely insensitive to which nodes a task's memory actually is on. > > Current upstream task memory allocation prefers to use the node the task is > currently running on (unless explicitly told otherwise, see > mbind()/set_mempolicy()), and with the scheduler free to move the task about at > will, the task's memory can end up being spread all over the machine's nodes. > > While the scheduler does a reasonable job of keeping short running tasks on a > single node (by means of simply not doing the cross-node migration very often), > it completely blows for long-running processes with a large memory footprint. > > This patch-set aims at improving this situation. It does so by assigning a > preferred, or home, node to every process/thread_group. Memory allocation is > then directed by this preference instead of the node the task might actually be > running on momentarily. The load-balancer is also modified to prefer running > the task on its home-node, although not at the cost of letting CPUs go idle or > at the cost of execution fairness. <snip> > [24/26] mm, mpol: Implement numa_group RSS accounting I was going to try and test this on power, but it fails to build: mm/filemap_xip.c: In function ‘__xip_unmap’: mm/filemap_xip.c:199: error: implicit declaration of function ‘numa_add_vma_counter’ and I think > [26/26] sched, numa: A few debug bits introduced a new warning: kernel/sched/numa.c: In function ‘process_cpu_runtime’: kernel/sched/numa.c:210: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 3 has type ‘u64’ kernel/sched/numa.c:210: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 4 has type ‘u64’ Thanks, Nish -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href