What is the best file system (used by an Amazon EBS volume) for a lucene index?
Here is a comparison of Various Linux filesystems (ext4,btrfs,nilfs2,xfs).
Phoronix Comparison of FileSystems
Since you require fast reads on the Index
NILFS2 has better random read performance
EXT3 has better multi threaded read performance
EXT4 has better overall performance.
I would say , you should choose between these three.
ps: Surprisingly BTRFS beats XFS in SQL CRUD performance.