Performance issue

[jacob-carlborg]

Simple test-case:
http://pastebin.com/dcnm4nmA

That's around 15k keys. It takes 31 seconds to serialize. And my
structures are full of these hashes, so it would likely take an
eternity to serialize my structures with Orange.

Here's msgpack-d:
http://pastebin.com/wsRQPiDJ

6.3 milliseconds to serialize. But it takes 32 milliseconds to
unserialize, which is 5x slower. On big data structures this
difference becomes quite noticeable.

[Numpsy]

fwiw, I tried running a profiler on that test case and that suggested that it spends most of its runtime inside Serializer.postProcessArrays().

This is DMD 2.059 on Windows, using the Sleepy profiler.

[jacob-carlborg]

I'm getting around 23 seconds with DMD 2.059 and around 9.5 seconds using DMD 1.072 with Tango. I'm compiling on Mac OS X 32bit.

[Numpsy]

I get ~7 seconds on this pc, and the profiler says:

        private void postProcessArrays ()
        {
            bool foundSlice = true;

            foreach (sliceKey, slice ; serializedArrays)
            {
3.22s           foreach (arrayKey, array ; serializedArrays)
                {
0.71s               if (slice.isSliceOf(array) && slice != array)
                    {
                        auto s = Slice(slice.length, (slice.ptr - array.ptr) / slice.elementSize);
                        archive.archiveSlice(s, sliceKey, arrayKey);
0.08s                   foundSlice = true;
                        break;
                    }

                    else
0.51s                   foundSlice = false;
                }

                if (!foundSlice)
                    archive.postProcessArray(sliceKey);
            }
        }

[jacob-carlborg]

Thanks, I'll do some investigation. BTW, are those 7 seconds with Tango?

[Numpsy]

Thats DMD2.059 on a 3.4ghz Intel Q6600, built with -O -inline -release. (i havent tested with noboundscheck, as i was building with xfbuild and that makes it fall over DMD bug 7478).

The same test takes ~14 seconds on the 3ghz Athlon64 X2 i have at work.