Re: [f2fs-dev] [PATCH] f2fs: introduce sysfs/data_io_flag to attach REQ_META/FUA

[Jaegeuk Kim]

On 04/07, Chao Yu wrote:
> On 2020/4/7 10:59, Jaegeuk Kim wrote:
> > On 04/07, Chao Yu wrote:
> >> On 2020/4/4 0:12, Jaegeuk Kim wrote:
> >>> This patch introduces a way to attach REQ_META/FUA explicitly
> >>> to all the data writes given temperature.
> >>>
> >>> -> attach REQ_FUA to Hot Data writes
> >>>
> >>> -> attach REQ_FUA to Hot|Warm Data writes
> >>>
> >>> -> attach REQ_FUA to Hot|Warm|Cold Data writes
> >>>
> >>> -> attach REQ_FUA to Hot|Warm|Cold Data writes as well as
> >>>           REQ_META to Hot Data writes
> >>
> >> Out of curiosity, what scenario it is used for?
> > 
> > It's testing purpose to compare the bandwidths per different IO flags.
> 
> Thanks for the hint. :)
> 
> As nobarrier was set in Android, so REQ_PREFLUSH will not be considered in
> this sysfs interface?

I don't see any diff on performance, so not interesting. :)

> 
> Thanks,
> 
> > 
> >>
> >> Thanks,
> > .
> >