diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2024-03-15 14:08:21 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-03-26 11:07:20 -0700 |
| commit | 9cecde80aae0fb0aa44425575d5aca71bc646d89 (patch) | |
| tree | a83f883a6029075b4b69be99e80decc8db3ba56b /include | |
| parent | 7844c01472119f55bd9a107a4578a6d26be04c46 (diff) | |
mm: increase folio batch size
On a 104 thread, 2 socket Skylake system, Intel report a 4.7% performance
reduction with will-it-scale page_fault2. This was due to reducing the
size of the batch from 32 to 15. Increasing the folio batch size from 15
to 31 gives a performance increase of 12.5% relative to the original, or
17.2% relative to the reduced performance commit.
The penalty of this commit is an additional 128 bytes of stack usage. Six
folio_batches are also allocated from percpu memory in cpu_fbatches so
that will be an additional 768 bytes of percpu memory (per CPU). Tim Chen
originally submitted a patch like this in 2020:
https://lore.kernel.org/linux-mm/d1cc9f12a8ad6c2a52cb600d93b06b064f2bbc57.1593205965.git.tim.c.chen@linux.intel.com/
Link: https://lkml.kernel.org/r/20240315140823.2478146-1-willy@infradead.org
Fixes: 99fbb6bfc16f ("mm: make folios_put() the basis of release_pages()")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Yujie Liu <yujie.liu@intel.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202403151058.7048f6a8-oliver.sang@intel.com
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/pagevec.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/pagevec.h b/include/linux/pagevec.h index fcc06c300a72..5d3a0cccc6bf 100644 --- a/include/linux/pagevec.h +++ b/include/linux/pagevec.h @@ -11,8 +11,8 @@ #include <linux/types.h> -/* 15 pointers + header align the folio_batch structure to a power of two */ -#define PAGEVEC_SIZE 15 +/* 31 pointers + header align the folio_batch structure to a power of two */ +#define PAGEVEC_SIZE 31 struct folio; |