http://3cbzkrvakrpetjjppdwzbzqrlkmzatjs7jbyazap5gwutj32gcltjpqd.onion
Then, I thought, maybe I could use btrfs with LZO compression to reduce the amount of I/O and speed things up further? Analysis showed things were mostly slow due to I/O, not CPU, constraints. The conversion Rather than use the btrfs in-place conversion from ext4 , I opted to dar it up (like tar), run mkfs.btrfs on the SD card, then unpack the archive back onto it.