diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2021-11-05 21:35:27 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-11-06 21:30:33 +0100 |
| commit | 554b0f3ca6f4948fdbab5f199858d902061318d0 (patch) | |
| tree | 2d64713fbc901708c7937970a768174446a4cb74 /mm/Kconfig | |
| parent | mm, slub: use prefetchw instead of prefetch (diff) | |
| download | linux-554b0f3ca6f4948fdbab5f199858d902061318d0.tar.xz linux-554b0f3ca6f4948fdbab5f199858d902061318d0.zip | |
mm: disable NUMA_BALANCING_DEFAULT_ENABLED and TRANSPARENT_HUGEPAGE on PREEMPT_RT
TRANSPARENT_HUGEPAGE:
There are potential non-deterministic delays to an RT thread if a
critical memory region is not THP-aligned and a non-RT buffer is
located in the same hugepage-aligned region. It's also possible for an
unrelated thread to migrate pages belonging to an RT task incurring
unexpected page faults due to memory defragmentation even if
khugepaged is disabled.
Regular HUGEPAGEs are not affected by this can be used.
NUMA_BALANCING:
There is a non-deterministic delay to mark PTEs PROT_NONE to gather
NUMA fault samples, increased page faults of regions even if mlocked
and non-deterministic delays when migrating pages.
[Mel Gorman worded 99% of the commit description].
Link: https://lore.kernel.org/all/20200304091159.GN3818@techsingularity.net/
Link: https://lore.kernel.org/all/20211026165100.ahz5bkx44lrrw5pt@linutronix.de/
Link: https://lkml.kernel.org/r/20211028143327.hfbxjze7palrpfgp@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index d16ba9249bc5..9f1e0098522c 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -371,7 +371,7 @@ config NOMMU_INITIAL_TRIM_EXCESS config TRANSPARENT_HUGEPAGE bool "Transparent Hugepage Support" - depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE + depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT select COMPACTION select XARRAY_MULTI help |