On Sat, Jun 17, 2017 at 08:15:05PM -0700, Dan Williams wrote: > The hang up is that it requires per-fs enabling as it needs to be > careful to manage mmap_sem vs fs journal locks for example. I know the > in-development NOVA [1] filesystem is planning to support this out of > the gate. ext4 would be open to implementing it, but I think xfs is > cold on the idea. Christoph originally proposed it here [2], before > Dave went on to propose immutable semantics. > > [1]: https://github.com/NVSL/NOVA > [2]: https://lists.01.org/pipermail/linux-nvdimm/2016-February/004609.html And I stand to that statement. Let's get DAX stable first, and properly cleaned up (e.g. follow on work with separating it entirely from the block device). Then think hard about how most of the persistent memory technologies actually work, including the point that for a lot of workloads page cache will be required at least on the write side. And then come up with actual real use cases and we can look into it. And stop trying to shoe-horn crap like this in.
