Expected Performance

[gordan-bobic]

I found this project by following a link from here:
https://github.com/xmrMiner/xmrMiner

I am curious about something mentioned on that page, specifically about performance being compared to ccminer-cryptonight "patched version to support memory >4GiB".
The reason it piqued my interest is because it mentions performance of over 1600 H/s on a P100 which is quite similar to a 1080Ti, yet a 1080Ti only manages less than 1000 H/s with memory OC-ed.

What is this "> 4GiB memory" patch it mentions?