I have an 240gb image store of approximately 1.5 million entries. About half of these entries are image files (4 to 100kb) and the other half of these entries are deeply nested directories. Approximately half of these images are duplicates and have since been made into hard links to each other.
I'm in the process of pulling down a backup of this filesystem and putting it on a local test server with the intention to drastically modify the directory layout and test the changes.
Normally, I would just set up the file system that these images live on as ext4 (don't screw the default unless you have to), but I am wondering if there is a better option for this particular use case.
I have already researched XFS, ext3, ext4, and btrfs, but haven't found any solid benchmark demonstrating that I should pick one over the other for this particular task.
I am also limited by the kernel available by default on Ubuntu 10.04, but will recompile if the reason is good enough.