Update info re mixed raid levels Web-UI compatibility #468

[phillxnet]

This pull request's proposal

Updates main Pools doc entry re mixed raid profiles, and newer supported profile info. Also moves mixed raid info previously located in stable_kernel_backport.rst and updates that page to reflect upstream parity raid read-write defaults. Some minor rewording of existing content.

Incidental update re zstd compression addition.

Fixes #468

Checklist

• With the proposed changes no Sphinx errors or warnings are generated.
• I have added my name to the AUTHORS file, if required (descending alphabetical order).

[phillxnet]

Noting the outstanding and unrelated linkcheck failure of:

(interface/overview: line 178) broken https://www.duckdns.org - 404 Client Error: Not Found for url: https://www.duckdns.org/
473

Already issued via: #514

[Hooverdan96]

Please take the suggestions as you want, or not ...

Otherwise, I think that's a great update of this topic across multiple documents!!! Thank you!

[phillxnet]

@Hooverdan96 Thanks for the review, as always much appreciated. All suggestions bar one applied, with some context for my existing use of the semi-colon there :).

Otherwise, I think that's a great update of this topic across multiple documents!!! Thank you!

Thanks. We have rather neglected these doc entries for the last 2 years, hence diving in just now ready for our next Stable release. We should also document how to retrieve all btrfs patches that have been applied to the vanilla 6.4 kernel our 15.6 OS base carries. This came up in a discussion with @FroggyFlox recently and I believe we have something of the sort from a few years ago on the forum somewhere. That way we enable folks to check for specific fixes they may have heard of in upstream btrfs developments. Do you fancy creating a doc issue for that? We can then point folks at it when they have specific questions as to the openSUSE kernel we use. And potentially serve as a deterant to using our Stable kernel backport howto. If fact that would be a good placed for this suggestion: where folks can surface their particular kernels backported btrfs patches.

[FroggyFlox]

Thanks a lot for all of this, @phillxnet and @Hooverdan96 !

Regarding checking the back ports in our kernel, I was thinking about the same thing so I agree. I believe the post to which you are referring is the following: https://forum.rockstor.com/t/unresponsive-system/6616/21?u=flox

[phillxnet]

@FroggyFlox Thanks for digging up that forum post, I thought it was you that posted it way back then; nearly 5 years ago :).

[phillxnet]

PR product PRODUCTION published.