> has much better performance for small sync writes

I spent some time researching this topic, and in all benchmarks I've seen and my personal tests btrfs is faster or much faster: https://www.reddit.com/r/zfs/comments/1i3yjpt/very_poor_perf...

Thanks for sharing! I just setup a fs benchmark system and I'll run your fio command so we can compare results. I have a question about your fio args though. I think "--ioengine=sync" and "--iodepth=16" are incompatible, in the sense that iodepth will only be 1.

"Note that increasing iodepth beyond 1 will not affect synchronous ioengines"[1]

Is there a reason you used that ioengine as opposed to, for example, "libaio" with a "--direct=1" flag?

[1] https://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-...