I have a drive intended to be shared between Ubuntu and Windows. I've tried exFAT and NTFS and have noticed that both have high CPU load. For example, while bringing up a couple of Vagrant instances, the mount.ntfs process uses about 90% of a core, while exFAT generally pegs one at 100%. I've attempted and failed to get exfat-nofuse (https://github.com/dorimanx/exfat-nofuse) to install; there were make errors that appear to require development attention. So, are there read/write filesystems that will perform well and work in both Ubuntu and Windows?