Re: Race to power off harming SATA SSDs

James Bottomley
2017-04-10T23:58:00Z

On Tue, 2017-04-11 at 08:52 +0900, Tejun Heo wrote:
[...]
> > Any comments? Any clues on how to make the delay "smarter" to
> > trigger only once during platform shutdown, but still trigger per
> > -device when doing per-device hotswapping ?
>
> So, if this is actually an issue, sure, we can try to work around;
> however, can we first confirm that this has any other consequences
> than a SMART counter being bumped up? I'm not sure how meaningful
> that is in itself.

Seconded; especially as the proposed patch is way too invasive: we run
single threaded on shutdown and making every disk wait 1s is going to
drive enterprises crazy. I'm with Tejun: If the device replies GOOD to
SYNCHRONIZE CACHE, that means we're entitled to assume all written data
is safely on non-volatile media and any "essential housekeeping" can be
redone if the power goes away.

James