Multi-head logging Multi-level hash table for directory entries Static/Dynamic hot and cold data separation Adaptive logging scheme Configurable operational units Dual checkpoint Roll-back and roll-forward recovery Heap-style block allocation TRIM/FITRIM support[6] Online fs defragmentation/file defragmentation[7] Inline xattrs[8]/data[9]/dir[10] Offline filesystem check (Check and fix inconsistency[11]) Atomic operations[12] Filesystem-level encryption[13] Offline resizing[14] Inner periodically data flush[15] Extent cache[16] Transparent file compression[3][4]