I wanted to try out the new GPT system, and used it to partition my new HDD, with the partitions themselves using ext4. For some reason, about 1-2% of the space in each partition is already shown as used, both in df and gparted. Currently the only content of the partitions is the lost+found folder which occupies all of 16K.Is there a reason for this? Can this be fixed? Or is this just the space used by the file table (or equivalent)?Edit: Is this more related ext4 than GPT? I found this just now, ext4: How to account for the filesystem space?
GPT Partition - Used Space immediately after creating partition
partition;gpt
1-5% is reserved for root and as overhead for the filesystem.  It is NORMAL. This is done is to leave root that 1-5% so if the users on the machine fill the disk up, critical system processes and the root user still have a small chunk to play with.  As jordanm pointed out, the reserved space is also used to reduce filesystem fragmentation.You can use tune2fs -m 1.0 /dev/sda2 to lower the default 5% to 1%. Please note that it is not recommended to use -m 0 but still can be done.