Reduce memory consumption

[jangko]

The memory usage stat is here.

The interesting part is AsyncFD. Both Blockchain test and GeneralState test does not using anything async. Where does it come from?

EDIT: scroll the stat table to the right if you want to see the alloc freq and avg size.

[arnetheduck]

the is/was a bug in chronos that would initialize things only from importing them, could that be it? status-im/nim-chronos#46

[arnetheduck]

@cheatfate

[cheatfate]

The only place where we using KeyValuePairSeq is HashSet, which is used only for Windows and usage is pretty simple. We using it only for checking if AsyncFD is already registered in queue, because on Windows its hard to obtain such information.
https://github.com/status-im/nim-chronos/blob/master/chronos/asyncloop.nim#L365-L370

@jangko could we get not only Windows memory consumption?

[jangko]

I already updated the mem stat here.

new columns are: deallocSize, deallocFreq, unfreed

also add mem stat from macosx and linux.

a stat of @cheatfate test code.

the mysterious AsyncFD is still there although metrics already turned off.

[jangko]

fixed by #441 and #442, closing