Fyi ethos users. If you're getting opencl error -38 not enough space to allocate dag on 8GB RX 470-580, run sudo update-miner claymore to fetch v15.

I have no idea why the "current/default" version v11.9 seem to choke on epoch #298 on some of my rigs, at different times, but that is what is happening and that is the "solution."