Can Rockstor use SSD as cache?

[phillxnet (Philip Guyton)]

@Hooverdan & @Dude We do have a now old, from our CentOS days, developer reference for our bcache compatibility requirements regarding udev modifications written up in the following Wiki entry:

Bcache - developers notes

This document represents the current and pending state of bcache in Rockstor and is not an endorsement of it’s use or support status but is simply intended to share the progress and development made to date. It is intended as a developers document so any changes made should be in accordance with keeping this text up to date with the current code state, including in the case pending pr’s. If you wish to comment on bcache support in general, as opposed to the specifics of what is actually in play…

But ignore the “Building bcache“ section in the above as it should be available via an openSUSE package.

Back-then we did add the capability to recognise, and present within the Web-UI, bcache configured devices as indicated in the Wiki notes above. But we have no Web-UI capability to do the actual config - at least not yet. So that would all be a CLI thing. And potentially non-trivial if one is unfamiliar with such things.

What @Hooverdan stated re considering a pure ssd pool for application specific use, or part use, is way simpler than setting up an ssd bcache for other devices. Plus we have heard from very few folks actually trying bcache on Rockstor. So it is considered untested/unknown currently. But we should still recognise such devices once they are CLI configured.

Hope that helps.