Re: Benchmarking objrmap under memory pressure

Andrew Morton
2004-04-13T07:51:33Z

"Martin J. Bligh" <mbligh@aracnet.com> wrote:
>
> UP Athlon 2100+ with 512Mb of RAM. Rebooted clean before each test
> then did "make clean; make vmlinux; make clean". Then I timed a
> "make -j 256 vmlinux" to get some testing under mem pressure.
>
> I was trying to test the overhead of objrmap under memory pressure,
> but it seems it's actually distinctly negative overhead - rather pleasing
> really ;-)
>
> 2.6.5
> 225.18user 30.05system 6:33.72elapsed 64%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (37590major+2604444minor)pagefaults 0swaps
>
> 2.6.5-anon_mm
> 224.53user 26.00system 5:29.08elapsed 76%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (29127major+2577211minor)pagefaults 0swaps

A four second reduction in system time caused a one minute reduction in
runtime? Pull the other one ;)

Average of five runs, please...