Re: Disk spin-up optimization during system resume

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, 2014-01-17 at 05:21 -0500, Tejun Heo wrote:
> Hello,
> 
> On Fri, Jan 17, 2014 at 11:16:49AM +0100, Oliver Neukum wrote:
> > The START-STOP may result in an error. What do you do in that case?
> 
> At least for libata, worrying about suspend/resume failures don't make
> whole lot of sense.  If suspend failed, just proceed with suspend.  If
> the device can't be woken up afterwards, that's that.

The specific worry is the writeback cache.  If the flush fails and we
power down with dirty blocks in the cache, those blocks are lost but the
filesystem still thinks they're committed.  I think as long as you're
using flush barriers on your system, this isn't a problem, but if you're
not using barriers, it can lead to undetected corruption that blows up
later.  If it were a choice between suspend my laptop and save my data,
I'd choose the latter.  But the question is do we care ... perhaps we
can just say you have to use flush barriers if you want to suspend.

James



--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [SCSI Target Devel]     [Linux SCSI Target Infrastructure]     [Kernel Newbies]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Linux IIO]     [Samba]     [Device Mapper]
  Powered by Linux