“The current implementation of zvol uses a single taskq, leading to lock contention under heavy load and consequently decreased throughput. Introducing multiple taskqs and implementing a switch based on IO offset can alleviate this lock contention, thus improving overall throughput.”

https://github.com/openzfs/zfs/pull/15992

https://github.com/openzfs/zfs/commit/99741bde59d1d1df0963009bb624ddc105f7d8dc