Information about settings in config.yml

Hello.
Thanks for using your time reading my topic. All good with you ?
I need information about some settings in config.yml and searching in internet not see any details.

In section Core
"PPU LLVM Greedy Mode:"
That setting works if enabled ? What action does ? Performance ?
I see RPCS3 recompiling PPU modules changing that setting.

"Accurate RSX reservation access"
Is required to be enabled if the CPU not does TSX ?

"Accurate PPU 128-byte Reservation Op Max Length: -1"
That setting is for accuracy or performance when "always enabled" ?

"Full Width AVX-512: false"
My CPU does only AVX .. not any AVX-512. Thus being is better disabled for CPU AVX ?

In section GPU
"Disable MSL Fast Math: false"
Does better performance ? Can break graphics ?

"VRAM allocation limit (MB): 65536"
That setting limit the maximum vram allocation usage ? If yes the values are in KB or MB or MiB ?
The correct is use the current VRAM memory size ?

Thanks for reading.
Have an nice week.