linux_dsm_epyc7002/arch/powerpc
Mel Gorman 4f9b16a647 mm: disable zone_reclaim_mode by default
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 degradation due to
zone_reclaim_mode being enabled 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.

This patch (of 2):

zone_reclaim_mode causes processes to prefer reclaiming memory from
local node instead of spilling over to other nodes.  This made sense
initially when NUMA machines were almost exclusively HPC and the
workload was partitioned into nodes.  The NUMA penalties were
sufficiently high to justify reclaiming the memory.  On current machines
and workloads it is often the case that zone_reclaim_mode destroys
performance but not all users know how to detect this.  Favour the
common case and disable it by default.  Users that are sophisticated
enough to know they need zone_reclaim_mode will detect it.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:59 -07:00
..
boot powerpc: Bump BOOT_COMMAND_LINE_SIZE to 2048 2014-04-28 16:32:02 +10:00
configs USB: remove CONFIG_USB_DEBUG from defconfig files 2014-05-28 09:40:45 -07:00
crypto powerpc: Fix compile of sha1-powerpc-asm.S on 32-bit 2013-03-05 16:56:26 +11:00
include mm: disable zone_reclaim_mode by default 2014-06-04 16:53:59 -07:00
kernel DeviceTree for 3.16: 2014-06-04 10:02:38 -07:00
kvm At over 200 commits, covering almost all supported architectures, this 2014-06-04 08:47:12 -07:00
lib selftests/powerpc: Import Anton's memcpy / copy_tofrom_user tests 2014-03-07 15:53:12 +11:00
math-emu powerpc: Correct emulated mtfsf instruction 2014-04-07 10:33:11 +10:00
mm hugetlb: restrict hugepage_migration_support() to x86_64 2014-06-04 16:53:51 -07:00
net net: filter: add jited flag to indicate jit compiled filters 2014-03-31 00:45:08 -04:00
oprofile cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} 2014-03-19 14:10:24 +01:00
perf powerpc/perf/hv-24x7: Catalog version number is be64, not be32 2014-04-28 16:31:50 +10:00
platforms DeviceTree for 3.16: 2014-06-04 10:02:38 -07:00
sysdev of: Stop naming platform_device using dcr address 2014-05-23 08:28:02 +09:00
xmon powerpc: Fix xmon disassembler for little-endian 2014-03-07 15:50:12 +11:00
Kconfig Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
Kconfig.debug Merge branch 'kconfig-diet' from Dave Hansen 2013-07-04 11:25:51 -07:00
Makefile powerpc: Fix 64 bit builds with binutils 2.24 2014-05-28 13:24:05 +10:00
relocs_check.pl Fix warning typo "CONFIG_RELCOATABLE" 2013-05-29 15:11:30 +02:00