The filesystem tested in the second benchmark was created at the same geographical location on the disk but with different features :
Features not selected : resize_inode ; huge_file ; dir_nlink ; extra_isize
Block-size = 4096 - inode-ratio = 262144 - inode_size =128
Blocks reserved for root : 1%
The results show significant differences :
1/ Performances are boosted in the second benchmark on all operations (read, write...) on filesizes >= 1G that is to say above the caches/buffer-caches size I believe by 20 to 50%
2/ Reader / Re-Reader / Backward read / Stride read tests show a significant performance drop (about -20%) on operations on filesizes < 2M with +40 to +200% cpu consumption.