Ext4 Volume Unallocated Space

[fringe sparrow]

Hello general question around Ext4 volumes. After using disks to format the volume their is unallocated space 1TB volume has 936GB that is usable for example. I read that with ssd and hdd its best to leave 10%-20% of the volume unallocated for better performance in the case of the former and less degradation of the device in the case of later.

Because disks automatically allocates 64GB to be unallocated do I need to follow this guidance when filling the volume with data?

[smoky mountain]

you can fill it as much as the OS lets you. ext4 auutomatically reserves 5% of total partition size for system critical protection

see lsblk -o name,type,model,label,size,fstype,fssize,fsused,fsavail

1 TB METRIC is 931 GiB (binary prefix) btw just thru pure math

terminal lsblk shows always binary prefix sizes