When it was introduced, zone_reclaim_mode made sense as NUMA distances punished and workloads were generally partitioned to fit into a NUMA node. NUMA machines are now common but few of the workloads are NUMA-aware and it's routine to see major performance due to zone_reclaim_mode being disabled but relatively few can identify the problem.
Those that require zone_reclaim_mode are likely to be able to detect when it needs to be enabled and tune appropriately so lets have a sensible default for the bulk of users. Documentation/sysctl/vm.txt | 17 +++++++++-------- include/linux/mmzone.h | 1 - mm/page_alloc.c | 17 +---------------- 3 files changed, 10 insertions(+), 25 deletions(-) -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/