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authorChristoph Lameter <clameter@sgi.com>2006-04-13 18:23:53 -0700
committerTony Luck <tony.luck@intel.com>2006-04-21 10:57:40 -0700
commite5ecc192dfc5e0b325dd8c99ce4c755714c9acbf (patch)
tree04b1d9d8936727a5b7dec4ee912b5509853cfec6
parenta72391e42f0a13116995045b3d492d660f96697d (diff)
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[IA64] Setup an IA64 specific reclaim distance
RECLAIM_DISTANCE is checked on bootup against the SLIT table distances. Zone reclaim is important for system that have higher latencies but not for systems that have multiple nodes on one motherboard and therefore low latencies. We found that on motherboard latencies are typically 1 to 1.4 of local memory access speed whereas multinode systems which benefit from zone reclaim have usually more than 1.5 times the latency of a local access. Set the reclaim distance for IA64 to 1.5 times. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
-rw-r--r--include/asm-ia64/topology.h5
1 files changed, 5 insertions, 0 deletions
diff --git a/include/asm-ia64/topology.h b/include/asm-ia64/topology.h
index 3ee19dfa46df..616b5ed2aa72 100644
--- a/include/asm-ia64/topology.h
+++ b/include/asm-ia64/topology.h
@@ -23,6 +23,11 @@
#define PENALTY_FOR_NODE_WITH_CPUS 255
/*
+ * Distance above which we begin to use zone reclaim
+ */
+#define RECLAIM_DISTANCE 15
+
+/*
* Returns the number of the node containing CPU 'cpu'
*/
#define cpu_to_node(cpu) (int)(cpu_to_node_map[cpu])