EXT3, EXT4, and Btrfs all did well when it came to measuring the read performance with large (8GB) files, while falling behind were XFS and then NILFS2.
When running 12 clients through Dbench, the newer EXT4 file-system was substantially slower than EXT3 while the NILFS2 file-system finally captured a second place finish. In third was Btrfs with followed by EXT4 and XFS in last.
Turning to the Threaded I/O Tester with 32 threads of 64MB writes, the best latency was found on XFS, but between that and EXT4 was just a 24 microsecond difference. In third was Btrfs with a latency of just 79 microseconds greater than EXT4. Taking another position in last was NILFS2.