Please consider subscribing to LWN Subscriptions are the lifeblood of LWN.net. If you appreciate this content and would like to see more of it, your subscription will help to ensure that LWN continues to thrive. Please visit this page to join up and keep LWN on the net. Linux has a lot of filesystems, but two of them (ext4 and btrfs) tend to get most of the attention. In his 2012 linux.conf.au tal