The following improvements were implemented on the file systems supported by the current version of UEK:

btrfs Updates

• Patches were applied to support the ability to delete a device by specifying device ID. This feature enables functionality in the latest btrfs-progs package that is available for Oracle Linux 7 update 4 and later.

• Upstream patches were applied to better handle dedupe which was changing the mtime on files. This caused some applications, such as rsync, to incorrectly assert that file contents had changed. The patch helps to ensure that dedupe is transparent to the user.

• A fix has been included for an issue that caused a crash when removing a file where flush_space() did not overwrite the return value for successful chunk allocation.

XFS Updates

• Upstream patches have been applied to provide for the ability to reconfigure XFS error handling. This includes changes to behavior on ENOSPC and error handling during unmount.

• Upstream patches were applied to resolve a very rare issue that caused XFS to emit warning messages when under extremely high I/O load when available memory is limited.

• Upstream patches were applied to resolve some XFS warning issues when clearing SUID and SGID bits and to better handle the removal of security labels.

OCFS2 Updates

Various patches were applied to improve cluster locking and tracking of locks to prevent deadlocks.