Why don't re packers use 7-Zip?
 

I'm just trying to figure our why all of you use FreeARC or ARC based compression nested of LZMA or LZMA2 (7Zip).

Doesn't ARC packing and unpacking use lot of RAM compared to LZMA ?

According to the test done by TomsHardware the compression difference is very minor between ARC and LZMA.

Why don't you try compressing a game using lzma and fa? You will know the difference soon


Plus repackers use fa for applying other precompressors and preprocessors with lzma, not actually for fa compression.

GOG used Rar compression for a couple of games "small games" final station for example
everyone have their own way for compressing files
everyone have every choice

Probably, GOG has enough download bandwidth so they don't care about file sizes.

No they just apply some kind of basic compression one algorithm for everything and it's probably Rar

I have tried LZMA ans FA and other stuff with them (SREP, PreComp ...) when I used FA it took longer to decompress. That's why I'm asking it here to make a decision on what to use. I'm kind of on the back foot with FA 'cos it's not in active development.

Well here the trade is with ratio and unpacking time. For GTA V (as example), most of the people who use repacks won't mind to sacrifice an hour more on decompression for around 30GB gain.

Cause repackers are not coders, adding a compression algo in 7zip requires writing code and compiling it where as in fa, you can do that with arc.ini. And that's all :)

and even if someone is willing then there are no documents available
but if you explore a bit you can do much more with 7zip, then you can ever think with arc

because lzma is inbuilt with unarc.dll so it can work and unpack faster , using an arc.ini file some bit slow unpacking hence some times repacker uses 7zip and many times uses on lzma. also cause incompatibility or crase in 7z.exe so it better to use lzma in ARC

Download Nioh and try
and then try

and soon you will understand why 7z<fa

you can even use 7z pipe to pipe in freearc this way