Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 722bde68 authored by Theodore Ts'o's avatar Theodore Ts'o
Browse files

ext4: Add fine print for the 32000 subdirectory limit 



Some poeple are reading the ext4 feature list too literally and create
dubious test cases involving very long filenames and 1k blocksize and
then complain when they run into an htree-imposed limit.  So add fine
print to the "fix 32000 subdirectory limit" ext4 feature.

Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 7a262f7c

Documentation/filesystems/ext4.txt

+4 −1
Original line number Diff line number Diff line
@@ -85,7 +85,7 @@ Note: More extensive information for getting started with ext4 can be 
* extent format more robust in face of on-disk corruption due to magics,

* internal redundancy in tree

* improved file allocation (multi-block alloc)

* fix 32000 subdirectory limit

* lift 32000 subdirectory limit imposed by i_links_count[1]

* nsec timestamps for mtime, atime, ctime, create time

* inode version field on disk (NFSv4, Lustre)

* reduced e2fsck time via uninit_bg feature
@@ -100,6 +100,9 @@ Note: More extensive information for getting started with ext4 can be 
* efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force

  the ordering)



[1] Filesystems with a block size of 1k may see a limit imposed by the

directory hash tree having a maximum depth of two.



2.2 Candidate features for future inclusion



* Online defrag (patches available but not well tested)