Linux 101 : Root user Reserved Blocks
Reserved Blocks, are disk blocks that are used by the root user in case of emergency - no space on the storage, ... -
When running the "df" command, we can see clearly that some storage is missing:
We notice that:
15G - used storage - plus 2.8G - available storage - equals 17.8G not 19G.
The missing storage are what Linux keeps as reserved blocks, in case the filesystem gets full.
We could check the reserved blocks using the below command:
For the "extN" filesystems, the reserved blocks make up about 5 per cent of all the blocks.
We could also checks the reserved blocks using the following command:
If you divide "13107" by "262144", we will get "0.049" which translates to around 5%.
We could change the percentage of the reserved blocks using the below command: