The EXT4 file-system today deprecated its journaled mode of the “data=journal” mount option. Following its deprecation, this mode is planned for removal in the year 2028.
The data=journal mode for EXT4 is where all file data and metadata is written to the file-system’s journal before being committed to the main file-system. In the event of a crash or power loss, the journal can then be replayed to recover the data.
The EXT4 data=journal mode is great for those very concerned about data integrity and safety but comes with significant hits to the write performance compared to the default ordered (data=ordered) mode or data=writeback. Using the journaled mode also disables delayed allocation and Direct I/O support.
EXT4 journal deprecated
Per today’s Git merge for Linux 7.3, the EXT4 data=journal feature is deprecated and support for it will be removed in early 2028 following the 2027 Linux LTS kernel version.



Ah, I see! From googling “data=ordered” is the default and does what you said. Still, why not leave it for those that want it?
Maintenance is not free? They still have to test it at the very least.
Yeah, but I thought the philosophy was not to break userspace. I’m fine with the removal if absolutely nobody uses it, but some have commented here being users of the feature