Hi,
Our current default root file system, ext3, is proving to be a bottleneck for SD card performance. Not only does it take a long time to format the partitions, but it also takes a long time to write to. This slows down creating images on SD cards a lot. I just did a very simple experiment running linaro-media-create, writing an Ubuntu Desktop image to an SD card:
ext3: 139.85user 35.27system 44:03.58elapsed 6%CPU (0avgtext+0avgdata 107360maxresident)k 2876115inputs+7048200outputs (958major+1677659minor)pagefaults 0swaps
btrfs: 146.52user 34.48system 19:57.16elapsed 15%CPU (0avgtext+0avgdata 107408maxresident)k 4417521inputs+6542992outputs (138major+1779874minor)pagefaults 0swaps
As I understand it, btrfs is considered OK for file systems running on systems that don't suffer from power failure, so for writing an image and testing it this should be fine.
So, what do people think about switching?