On Fri, Aug 12, 2011 at 4:11 PM, Arnd Bergmann arnd@arndb.de wrote:
On Friday 12 August 2011 21:12:54 Fathi Boudra wrote:
At the last release meeting, the switch to ext4 by default has been mentioned. My understanding is that we reach an agreement on the switch to ext4 [1] but it still not clear if it will happen this month.
To make it happen, it will require several bug fixes: https://bugs.launchpad.net/ubuntu/+source/linux-linaro-omap/+bug/817148 https://bugs.launchpad.net/linaro-image-tools/+bug/821479 https://bugs.launchpad.net/linaro-ubuntu/+bug/822593 https://bugs.launchpad.net/linux-linaro/+bug/824545
Also, it's worth mentioning that changing the default will break previous releases if they don't have ext4 support. The workaround is linaro-media-create --rootfs option to specify the filesystem.
I think it's also worthwhile to look at the results of Tixy's file system simulation before we switch. If there are significant performance regressions over ext3 or if btrfs turns out to be much better than ext4, we should probably not move to ext4 at this point but rather try to get btrfs fully supported. My understanding is that there are other bugs that would need to be fixed to make that happen.
Yeah, if we're doing this change it seems it would make more sense to jump directly to the btrfs, unless we can demonstrate that the performance is not that superior and have any kind of blocker issues.
Do we have any kind of benchmark results comparing each filesystem when using them with SD cards around?
Thanks,