To rephrase: consistency is related to a single stream of instructions being re-ordered, coherence is related to multi-streams accessing the same data.

Does the "reorder" mean that we still execute the instruction (read and write in one processor) as ordered, but for example we can just put some "write" to buffer that we don't care whether they are actually written to memory in order?

@zecheng I think it means truly reordering instructions here, like if you have a write to A followed by a read from B, the read could be put before the write.