forget deleting refs, I confused it with another project. On 4 October 2010 11:17, Lev Walkin <v...@lionet.info> wrote:
> > In some of my tests there were improvements in the order of single digit > percentages. That's a good enough for me to get rid of phashing now(). Don't > forget about GC implications of getting now() in and out. > > What do you mean you could delete refs? I believe refs are not better than > > On Oct 4, 2010, at 1:44 AM, eF wrote: > > I forked riak from github some time ago substitute erlang:phash2 with > make_ref. I did not reveal any significant performance jump ;) > > However I agree with you that make_ref just looks better and seems to be > more accurate. Actually, no hash is needed (at least in riak_client) because > it is used to match on specific messages (to not mix map/reds etc.) and we > can easily match on make_ref which is as good as any erlang term. > > My initial motivation was better control over memory (i.e. I could delete > refs), but there was no improvement also, so I gave up the idea. > > > Michal Zajda > > On 2 October 2010 16:00, Lev Walkin <v...@lionet.info> wrote: > >> >> In riak sources there are many references to erlang:phash2(erlang:now()). >> >> Why not use idiomatic make_ref() or at the very least >> erlang:phash2(make_ref()), which is faster? >> >> 1> perftest:comprehensive(100000, fun() -> erlang:phash2(erlang:now()) >> end). >> Sequential 100000 cycles in ~1 seconds (193510 cycles/s) >> Parallel 2 100000 cycles in ~1 seconds (187282 cycles/s) >> Parallel 4 100000 cycles in ~1 seconds (197310 cycles/s) >> Parallel 10 100000 cycles in ~1 seconds (182890 cycles/s) >> Parallel 100 100000 cycles in ~0 seconds (208671 cycles/s) >> [197310,182890,208671] >> 2> perftest:comprehensive(100000, fun() -> erlang:phash2(make_ref()) end). >> Sequential 100000 cycles in ~0 seconds (323952 cycles/s) >> Parallel 2 100000 cycles in ~0 seconds (301875 cycles/s) >> Parallel 4 100000 cycles in ~0 seconds (308568 cycles/s) >> Parallel 10 100000 cycles in ~0 seconds (287875 cycles/s) >> Parallel 100 100000 cycles in ~0 seconds (326416 cycles/s) >> [308568,287875,326416] >> 3> perftest:comprehensive(100000, fun() -> make_ref() end). >> Sequential 100000 cycles in ~0 seconds (1299765 cycles/s) >> Parallel 2 100000 cycles in ~0 seconds (934492 cycles/s) >> Parallel 4 100000 cycles in ~0 seconds (1111679 cycles/s) >> Parallel 10 100000 cycles in ~0 seconds (1241434 cycles/s) >> Parallel 100 100000 cycles in ~0 seconds (1264350 cycles/s) >> [1111679,1241434,1264350] >> 4> >> >> make_ref is 6 times faster than erlang:phash2(make_ref()) which is 50% >> faster than erlang:phash2(now()). >> >> Of course, in the grand scheme of things this might not be your biggest >> bottleneck, but why hashing now() when there exsists an idiomatic make_ref() >> solution? Am I missing something? >> >> -- >> Lev Walkin >> v...@lionet.info >> >> _______________________________________________ >> riak-users mailing list >> riak-users@lists.basho.com >> http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com >> > > > -- > vlm > >
_______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
