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

[Chao Yu]

On 2020/4/9 10:20, Jaegeuk Kim wrote:
> 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. :)

I doubt it may has diff on non-ufs/emmc device? just guess.

Thanks,

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