The default kernel on your Samsung Galaxy S9 and S9+ now let you control the CPU frequency so you are not able to underclock or overclcok it on demand but this custom kernel, Nemesis lets you do that and more. It also includes a RAMdisk and comes with pre defined CPU governors that let you get more speed or battery life.
1) Put the zip file in your SD Card. Download it from here https://www.androidfilehost.com/?w=files&flid=258501
2) Reboot in Recovery Mode (TWRP)
3) Install the Kernel
Features of the Nemesis custom kernel for the Galaxy S9/S9+.
– Build with latest 4.9 google toolchain
– Build with ARC5 kernel source code
– Latest Linux version 4.9.88, is always up to date
– Performance and Batterylife improved
– Choose between different CPU governors: performance, powersave, userspace, ondemand, interactiv, conservative, schedutil (default)
– Includes latest ARC5 ramdisk
– I/O schedulers: CFQ (Default), No-op, Deadline
– TCP (Network) control: Bic (default), Reno, cdg, cubic, dctcp, Westwood, Highspeed, Hybla, HTCP, Vegas, Veno, Scalable, LP, Yeah, Illinois, Lia, Olia, Wvegas, balia
– Selinux is set to permissive (settings will show enforcing to fake apps)
– All samsung security related configs disabled (as knox, tima, restrict rooting)