How to avoid disk overload?

[jgreco]

Thus there are incentives to feed files into long term storage thoughtfully.

The optimal way to feed files into long term RAIDZ storage is to treat it as write-once storage. Pretend that once you've written it, you cannot delete or alter it except by a unanimous act of Congress. Even the metadata updates cause fragmentation, so the closer you come to this ridiculous sounding suggestion, the more optimal the storage is.