My experience has been good with LXD and splitting MySQL out from the LAMP stack into a different container… I think some of my “issues” are at the application level and not the container level… I’ve just not gotten round to focusing deeply on the issue…
On both hosts I run, LXD has been excellent… I run everything in Debian on the host and only rarely do I run into problems and when I do, it’s almost always at the app level, as above!