Hi, Maybe this should really be an RFC, given that I don't fully understand why the compaction_test.c program was mmap'ing 1 MB at a time. So apologies in advance if I've mucked up something important, but if so, maybe we can still find a way to get this fixed up to something better. Anyway: there are 20+ tests in tools/testing/selftests/vm/. The entire running time for these (via run_vmtest.sh) is about 56 seconds, of which over half is due to just one test: compaction_test, which takes 27 sec! (A runner-up is HMM, at 11 sec, so it's up for a look next.) The other tests mostly take a few ms, and a few take 1.0 sec. This drops the compaction_test run time from 27, to 3.3 sec. Enjoy. :) thanks, John Hubbard NVIDIA John Hubbard (1): selftests/vm: 8x compaction_test speedup tools/testing/selftests/vm/compaction_test.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) -- 2.28.0