On Mon, 18 Jun 2007, Srivatsa Vaddagiri wrote: > This particular machine, elm3b6, is a 4-cpu, (gasp, yes!) 4-node box i.e > each CPU is a node by itself. If you don't have CONFIG_NUMA enabled, > then we won't have cross-node (i.e cross-cpu) load balancing. > Fortunately in your case you had CONFIG_NUMA enabled, but still were > hitting the (gross) load imbalance. > > The problem seems to be with idle_balance(). This particular routine, > invoked by schedule() on a idle cpu, walks up sched-domain hierarchy and > tries to balance in each domain that has SD_BALANCE_NEWIDLE flag set. > The nodes-level domain (SD_NODE_INIT) however doesn't set this flag, > which means idle cpu looks for (im)balance within its own node at most and
The nodes-level domain looks for internode balances between up to 16 nodes. It is not restricted to a single node. The balancing on the phys_domain level does balance within a node. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
