Tools: What file system?

On Linux, you have a plethora of File Systems available.

Recently I was testing databases (MySQL, MariaDB) especially with ThreadPool against a Violin Flash Memory Array, and I forgot what file system the LUN was mounted (and formatted) as.

There are two ways to find out:

• df -T (show mounted life systems, along with the FS type)
• file -s /dev/xxx (show more details about a FS node)

Generally I use ext2, ext3, ext4 -- but the new ZFS and Btrfs have some really exciting features.