mjhjmtu

I have been filling a hard drive and a couple of backup drives with the family pictures and videos. Once a video goes into the archive, it remains there in a folder correctly labeled with the date. The data collection has grown up to the point where I need a new drive (and new backup drives).

But I wonder why should I leave the reserved blank space linux enforces in the drive, which now is above 50 GB I could fill with more videos. It is easy to do that by invoking the 'cp' command as root.

Since I am not going to do anything else with the drive other than archival purposes, I wonder if filling that reserved space would be a bad practice, in this case, and why. I know I shouldn't do that with the main drive inside the laptop, otherwise the system may become unstable, but what about that external drive holding only archival data?

I assume that you are using an ext4 file system: You can modify the size of the reserved space with tune2fs. The following command line reduces the reserved space to 1% (from default 5%).

sudo tune2fs -m 1 /dev/sdxn

where x is the drive letter and n is the partition number (of a partition with an ext file system).

From man tune2fs:

 -m reserved-blocks-percentage
 Set the percentage of the filesystem which may only be allocated
 by privileged processes. Reserving some number of filesystem
 blocks for use by privileged processes is done to avoid filesys‐
 tem fragmentation, and to allow system daemons, such as sys‐
 logd(8), to continue to function correctly after non-privileged
 processes are prevented from writing to the filesystem. Nor‐
 mally, the default percentage of reserved blocks is 5%.

You can reduce the size of the reserved space in a data drive (which is not as critical as a system drive). But as described in the manual, space is reserved to

• avoid fragmentation (relevant also for a data partition)


• allow system daemons to continue to function correctly