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Hi, list!

I'm back again with another silly benchmark (thus, sorry for HTML formatting).

Now I'm finding the fastest way to calculate sum of values in array part of the table (ignoring hole issues).

Source: http://tinyurl.com/yh6mvc3

lua
-------------------------------------------------------------------
                name |     rel | abs s / iter = us (1e-6 s) / iter
-------------------------------------------------------------------
            unrolled |  1.0000 |  45.37 /   10000000 = 4.537000 us
         numeric_for |  1.2771 |  57.94 /   10000000 = 5.794000 us
       numeric_while |  1.6244 |  73.70 /   10000000 = 7.370000 us
               pairs |  3.2927 | 149.39 /   10000000 = 14.939000 us
              ipairs |  3.6846 | 167.17 /   10000000 = 16.717000 us
                next |  4.3198 | 195.99 /   10000000 = 19.599000 us
luajit2
-------------------------------------------------------------------
                name |     rel | abs s / iter = us (1e-6 s) / iter
-------------------------------------------------------------------
            unrolled |     nan |   0.00 /   10000000 = 0.000000 us
         numeric_for |     inf |   1.90 /   10000000 = 0.190000 us
              ipairs |     inf |   4.37 /   10000000 = 0.437000 us
       numeric_while |     inf |   4.43 /   10000000 = 0.443000 us
               pairs |     inf |  35.79 /   10000000 = 3.579000 us
                next |     inf |  45.99 /   10000000 = 4.599000 us

I'm surprised that (as my colleague pointed out to me), in plain Lua, pairs is faster than ipairs.

Also, in unpatched LuaJIT2 b2, pairs is much slower than ipairs and numeric for... I guess this is another one of beta issues (or I've screwed the benchmark somewhere), but reporting it just in case anyway.

Alexander.

P.S. To reproduce, clone

   http://github.com/agladysh/luamarca/

and run

   $ ./run_benchmark.sh bench/accum.lua 1e7