@atpfm @siracusa Late reply, but a “little checksum turds on the disk” program (chkbit) actually correctly detected a hardware issue I had. The Mac was eventually warranty repaired for that issue, though it passed all of Apple’s own hardware tests.

Interestingly, heavy repeated reads of the same data from disk would OCCASIONALLY come back corrupted and then later fix itself, so it’s possible it was a RAM issue and not a storage one.

Took me a while to be confident that the hardware was faulty.