NAND Flash so slow

Hello, i'm comming here to find a solution for a nand flash very very slow, that's why my O2X is very slow to open app, my nand flash read at 12MB/s and write at 4MB/s, i'm on the old bootloader with OptiX 6.0 with his stock kernel, I dont format system in F2FS.
Do you have a solution to improve this?
Thanks