You can also navigate the service by using the first alphabet letter of the service name on the keyboard.
You can directly open the Windows Services and find the SysMain service and then disable it.
Disable the SysMain service using Services Try the following methods to disable the SysMain service. If your computer has Hard Disk, you should think twice before deciding to disable this service as this service improves the application load time. Traditional Hard Disk Drive is a lot slower than the Solid State Drive. This data is further used to improve the system performance by arranging the hard disk at the block level. The SysMain process scans the hard disk and collects the data to determine which application you use most and which not. Service Host SysMain is also known as SuperFetch it is a service that runs in the background and continuously checks your computer behavior to improve system performance.
Service Host SysMain causing High Disk usage