What's the status of BTRFS RST instead of linux md raid5?

[Marc MERLIN <marc_btrfs@merlins.org>]

So, I'm aware that the built in btrfs raid5 support that's been there
for 10-ish years is not recommended due to hard to fix or unfixable
flaws.

But with raid5, once I have a checksum mismatch, btrfs could easily run
all combinations of the blocks to find out which one can be removed to
yield a correct checksum for that data block, but obviously those layers
don't talk, so nothing happens outside of btrfs telling me the checksum
is bad, and there is no good way to rebuild anything, especially when
it's bit rot in a read only snapshot where I cannot reasonably delete or
rewrite the file without some surgery.

Gemini tells me that RST with the future that fixes this so I can use
raid5 or raid6 directly in btrfs where everything talks to one another,
but I can't find good docs or status on RST.
Even this list has very little about RST outside of some old patches.

So, is RST kind of ready and documented, or is it still very
experimental and "read the source, luke" ?

Thanks,
Marc
-- 
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
 
Home page: http://marc.merlins.org/