On Sun, Jul 05, 2020 at 06:31:25PM -0300, Henrique de Moraes Holschuh wrote: > On Thu, 18 Jun 2020, Christoph Hellwig wrote: > > > For SSDs, I don't think an extra stop should ever be an issue. > > > > Extra shutdowns will usually cause additional P/E cycles. > > I am not so sure. We're talking about enforcing clean shutdowns here > (from the SSD PoV). > > A system reboot takes enough time that the SSD is likely to do about the > same amount of P cycles commiting to FLASH any important data that it > would trigger by a shutdown sequence, simply because it should not keep > important data in RAM for too long. By extension, it would not increase > E cycles either. > > OTOH, unclean shutdowns *always* cause extra P/E, and that's if you're > lucky enough for it to not cause anything much worse. The point is - with a normal system that doesn't required your odd reboot method we'll normally not shut down the SSD at all, and that won't require a P/E cycle. But the whole thing is a moot point - if you quirk your system to require a poweroff to reboot the kernel should trat it as a power off as far as shutdown/remove callbacks are concerned and everything will just work as intended.