]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
selftests/vm: 8x compaction_test speedup
authorJohn Hubbard <jhubbard@nvidia.com>
Tue, 13 Oct 2020 23:57:04 +0000 (16:57 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 14 Oct 2020 01:38:34 +0000 (18:38 -0700)
commit1100262037be8008cc85240389fbe5eac4df034d
tree02931b054859673f933fb7b98db8b71d3b9bd98e
parent74c9da4e1dc0ecf70e7fa78568821e3ed8f77938
selftests/vm: 8x compaction_test speedup

This patch reduces the running time for compaction_test from about 27 sec,
to 3.3 sec, which is about an 8x speedup.

These numbers are for an Intel x86_64 system with 32 GB of DRAM.

The compaction_test.c program was spending most of its time doing mmap(),
1 MB at a time, on about 25 GB of memory.

Instead, do the mmaps 100 MB at a time.  (Going past 100 MB doesn't make
things go much faster, because other parts of the program are using the
remaining time.)

Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Sri Jayaramappa <sjayaram@akamai.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Link: https://lkml.kernel.org/r/20201002080621.551044-2-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tools/testing/selftests/vm/compaction_test.c