kdiskmark using fio benchmark isn’t in a real world scenario.
I checked cat for reading a large game data 7z 30 GB in two different partitions (Ext4 and Btrfs) in the same Nvme SSD.
Open bash shell in terminal:
Btrfs
$ time cat Game.7z > /dev/null
real 0m18,430s
user 0m0,045s
sys 0m10,223s
18 sec reading is done
Ext4
$ time cat Game.7z > /dev/null
real 0m28,873s
user 0m0,053s
sys 0m12,955s
28 sec reading is done
However I don’t understand why.