I meant, it can be done in packaging level and it's much easier to do.
Its all about trade off, and there is no right or wrong, so is tough to arrive at a conclusion even before this was implemented. Below are the choices considered, now putting in the order of least suitable to most suitable after reviewing their advantages and disadvantages. . Update default features at the compile time, so to have a define set for the default choices per release/distro. (not sure how to do that), But with this, you can not solve the problem for which current "-O comp=" is provided (i.e to provide features which are compatible across a set of known kernels). And mainly, you are letting the control of such a discussion out of btrfs/mainline. Then distros will have own set of default features instead of having such an effort discussed and converged at the mainline. . /etc/btrfs.conf file to hold the default features (same as ext4) I have to drop this idea since from the user point of view you are creating another source of config/input that user/distro has to care about. . Do it at run time for the running kernel. Current. In the order of priority .. check sysfs, if not check kernel-version, if not use progs-version-based-defaults (original).
And it's much predictable than version based detection.
I think you mean to say its not predictable because it follows a priority list, and we won't know which system used sysfs/version/ progs-version. Concern is valid. But I feel its trivial, unless you have some strong reason. Further still its only a trade off that could achieve. Other concern that others commented.. if sysfs is not there and feature is backported, for this we should ensure sysfs feature is also backported along with the feature it self, without that feature back port is incomplete. If distro does not want to backport sysfs, the other choice that disto has is to update the feature-to-version table in the progs. For the system which does not provide version at all, it will fail back to the original progs-version-based-defaults. Hope I have captured all the concerns and addressed them. Thanks, Anand -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
