diff options
| author | Ebru Akagunduz <ebru.akagunduz@gmail.com> | 2016-07-26 15:25:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-26 16:19:19 -0700 |
| commit | 8a966ed746d63c8103d496da85973eeeec01d77f (patch) | |
| tree | a96bcdb72409c34910440549c2e4fa248a468c4e /include | |
| parent | 70652f6ec0566ae6b4147d88c6d043c68484227f (diff) | |
mm: make swapin readahead to improve thp collapse rate
This patch makes swapin readahead to improve thp collapse rate. When
khugepaged scanned pages, there can be a few of the pages in swap area.
With the patch THP can collapse 4kB pages into a THP when there are up
to max_ptes_swap swap ptes in a 2MB range.
The patch was tested with a test program that allocates 400B of memory,
writes to it, and then sleeps. I force the system to swap out all.
Afterwards, the test program touches the area by writing, it skips a
page in each 20 pages of the area.
Without the patch, system did not swap in readahead. THP rate was %65
of the program of the memory, it did not change over time.
With this patch, after 10 minutes of waiting khugepaged had collapsed
%99 of the program's memory.
[kirill.shutemov@linux.intel.com: trivial cleanup of exit path of the function]
[kirill.shutemov@linux.intel.com: __collapse_huge_page_swapin(): drop unused 'pte' parameter]
[kirill.shutemov@linux.intel.com: do not hold anon_vma lock during swap in]
Signed-off-by: Ebru Akagunduz <ebru.akagunduz@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/trace/events/huge_memory.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index fad6539c9d68..bda21183eb05 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -135,5 +135,29 @@ TRACE_EVENT(mm_collapse_huge_page_isolate, __print_symbolic(__entry->status, SCAN_STATUS)) ); +TRACE_EVENT(mm_collapse_huge_page_swapin, + + TP_PROTO(struct mm_struct *mm, int swapped_in, int ret), + + TP_ARGS(mm, swapped_in, ret), + + TP_STRUCT__entry( + __field(struct mm_struct *, mm) + __field(int, swapped_in) + __field(int, ret) + ), + + TP_fast_assign( + __entry->mm = mm; + __entry->swapped_in = swapped_in; + __entry->ret = ret; + ), + + TP_printk("mm=%p, swapped_in=%d, ret=%d", + __entry->mm, + __entry->swapped_in, + __entry->ret) +); + #endif /* __HUGE_MEMORY_H */ #include <trace/define_trace.h> |