Naoya Horiguchi d9b2ddf807 tools/vm/page-types.c: avoid memset() in walk_pfn() when count == 1 ... I found that page-types is very slow and my testing shows many timeout errors. Here's an example with a simple program allocating 1000 thps. $ time ./page-types -p $(pgrep -f test_alloc) ... real 0m17.201s user 0m16.889s sys 0m0.312s Most of time is spent in memset(). Currently memset() clears over whole buffer for every walk_pfn() call, which is inefficient when walk_pfn() is called from walk_vma(), because in that case walk_pfn() is called for each pfn. So this patch limits the zero initialization only for the first element. $ time ./page-types.patched -p $(pgrep -f test_alloc) ... real 0m0.182s user 0m0.046s sys 0m0.135s Fixes: 954e95584579 ("tools/vm/page-types.c: add memory cgroup dumping and filtering") Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Suggested-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2016-03-17 15:09:34 -07:00
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Makefile
page_owner_sort.c
page-types.c	tools/vm/page-types.c: avoid memset() in walk_pfn() when count == 1	2016-03-17 15:09:34 -07:00
slabinfo-gnuplot.sh
slabinfo.c