Setting zfs_dedup_prefetch=0 has been found to help systems using ZFS data deduplication. There is a patch in ZoL HEAD for the next release that makes zfs_dedup

Setting zfs_dedup_prefetch=0 has been found to help systems using ZFS data deduplication. There is a patch in ZoL HEAD for the next release that makes zfs_dedup_prefetch=0 by default: https://github.com/zfsonlinux/zfs/commit/0dfc732416922e1dd59028fa900d38d04dceaa12 https://github.com/zfsonlinux/zfs/commit/0dfc732416922e1dd59... Aside from that, you are right that there has not been much done here. Making data deduplication more performant is a difficult task and so far, no one has proposed improvements beyond trivial changes.