Examples relate to ordering updates for nonvolatile memory accesses. In some examples, a first update that is propagated from a write-through processor cache of a processor is received by a write ordering buffer, where the first update is associated with a first epoch. The first update is stored in a first buffer entry of the write ordering buffer. At this stage, a second update that is propagated from the write-through processor cache is received, where the second update is associated with a second epoch. A second buffer entry of the write ordering buffer is allocated to store the second update. The first buffer entry and the second buffer entry can then be evicted to non-volatile memory in epoch order.