Re: [PATCH] nvmet: disable direct I/O when unavailable

[Max Gurtovoy]

On 2/22/2019 7:55 AM, Johannes Thumshirn wrote:
> On 22/02/2019 01:41, Chaitanya Kulkarni wrote:
> [...]
> > As per specified in the patch, this is only useful for testing, then we
> > should modify the test scripts so that on creation of the ctrl we switch
> > to the buffered I/O before running fio.
> Or on any other file-system that does not support DIO..

Do we really want to support these kind of filesystems for fabrics 
backend device ? only for testing ?

What is the status of iSCSI/SRP targets in this case ?


> > OR
> >
> > Similar result can be achieved by setting buffered I/O flag
> > buffered_io=1 before enabling the name-space in the test script.
> Frankly, we have a ton of testing related special cases in the kernel.
>
> This one is a) simple and small, only 10 LoC, b) far away from the fast
> path or any other place where it could have any impact on legitimate
> users and c) it prints an informal message showing you what happened.
>
> Sorry but this is a https://xkcd.com/386/ moment.
>
> Byte,
> 	Johannes