Keeping enough free space should be much less of a problem with SSDs. They can tune it so the array needs to be 95% full before the slower best-fit allocator ki

Keeping enough free space should be much less of a problem with SSDs. They can tune it so the array needs to be 95% full before the slower best-fit allocator kicks in. https://openzfs.readthedocs.io/en/latest/performance-tuning.html#free-space https://openzfs.readthedocs.io/en/latest/performance-tuning.... I think that 80% figure is from when drives were much smaller and finding free space over that threshold with the first-fit allocator was harder.