Don’t use ZFS. It’s that simple. It was always more of a buzzword than anything else, I feel, and the licensing issues just make it a non-starter for me.
The benchmarks I’ve seen do not make ZFS look all that great. And as far as I can tell, it has no real maintenance behind it either any more, so from a long-term stability standpoint, why would you ever want to use it in the first place?
ZFS could be the fastest file system in the world and randomly disperse kittens and I still wouldn’t touch it with a ten metre pole if I were Linus. Oracle is a colony of snakes led by the biggest snake of them all, and adding their code – even through shims or interfaces – should be a complete non-starter for any project.