Re: Modern uses of CONFIG_XFS_RT

Brian Foster
2020-02-20T14:25:29Z

On Thu, Feb 20, 2020 at 02:41:06PM +1100, Dave Chinner wrote:
> On Wed, Feb 19, 2020 at 01:57:15PM +0000, Luis Chamberlain wrote:
> > I hear some folks still use CONFIG_XFS_RT, I was curious what was the
> > actual modern typical use case for it. I thought this was somewhat
> > realted to DAX use but upon a quick code inspection I see direct
> > realtionship.
>
> Facebook use it in production systems to separate large file data
> from metadata and small files. i.e. they use a small SSD based
> partition for the filesytem metadata and a spinning disk for
> the large scale data storage. Essentially simple teired storage.
>

Didn't this involve custom functionality? I thought they had posted
something at one point that wasn't seen through to merge, but I could be
misremembering (or maybe that was something else RT related). It doesn't
matter that much as there are probably other users out there, but I'm
not sure this serves as a great example use case if it did require
downstream customizations that aren't going to be generalized/supported
for the community.. Richard..?

Brian

> It's also commonly still used in multi-stream DVRs (think
> multi-camera security systems), and other similar sequential access
> data applications...
>
> That's just a couple off the top of my head...
>
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@fromorbit.com
>