Re: [PATCH 41/43] xfs: export zone stats in /proc/*/mountstats

Christoph Hellwig
2025-02-07T04:25:13Z

On Thu, Feb 06, 2025 at 05:02:24PM -0800, Darrick J. Wong wrote:
> I'm kinda surprised you didn't export this via sysfs, but then
> remembered that Greg has strict rules against tabular data and whatnot.
>
> > This gives good insight into data fragmentation and data placement
> > success rate.
>
> I hope it's worth exporting a bunch of stringly-structured data. ;)
>
> Past me would've asked if we could just export some json and let
> userspace pick that up, but today me learned about the horrors of json
> and how it represents integers, stumbling over trailing commas, etc.

Yeah, this is really mostly used for human debugging at the moment.

> Is any of this getting wired up into a zone-top tool?

Heh, for that we'd actually need to commit to a stable format. But
it does sound interesting. Combine with information from fsmap for
the persistent space usage on disk.