On Wed, Jan 19, 2022 at 09:12:27PM +0000, Dmitry Kozlyuk wrote: > Hi Bruce, > > > From: Bruce Richardson <bruce.richard...@intel.com> > > [...] > > this seems really interesting, but in the absense of TB of memory > > being > > used, is it easily possible to see the benefits of this work? I've > > been > > playing with adding large memory allocations to helloworld example and > > checking the runtime. Allocating 1GB using malloc per thread seems to > > show > > a small (<0.5 second at most) benefit, and using a fixed 10GB > > allocation > > using memzone_reserve at startup shows runtimes within the margin of > > error > > when run with --huge-unlink=existing vs huge-unlink=never. At what > > size of > > memory footprint is it expected to make a clear improvement? > > Sorry, there was a bug in v1 that completely broke the testing. > I should've double-checked > after what I considered a quick rebase before sending. > Version 2 can be simply tested even without modifyin the code: > > time sh -c 'echo quit | sudo ../_build/dpdk/app/test/dpdk-test > --huge-unlink=never -m 8192 --single-file-segments --no-pci > 2>/dev/null >/dev/null' > > With --huge-unlink=existing: > real 0m1.450s > user 0m0.574s > sys 0m0.706s (1) > > With --huge-unlink=never, first run (no hugepage files to reuse): > real 0m0.892s > user 0m0.002s > sys 0m0.718s (2) > > With --huge-unlink=never, second run (hugepage files left): > real 0m0.210s > user 0m0.010s > sys 0m0.021s (3) > > Notice that (1) and (2) are close since there is no reuse, > but (2) and (3) are differ by 0.7 seconds for 8GB, > which correlates with 14 GB/sec memset() speed on this machine. > Results without --single-file-segments are nearly identical.
Thanks, glad to hear it wasn't just me! I'll check again the v2 when I get the chance.
