khugepaged: introduce 'max_ptes_shared' tunable
'max_ptes_shared' specifies how many pages can be shared across multiple
processes. Exceeding the number would block the collapse::
/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_shared
A higher value may increase memory footprint for some workloads.
By default, at least half of pages has to be not shared.
[colin.king@canonical.com: fix several spelling mistakes]
Link: http://lkml.kernel.org/r/20200420084241.65433-1-colin.king@canonical.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Link: http://lkml.kernel.org/r/20200416160026.16538-9-kirill.shutemov@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 files changed