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DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Score: -4.51 On 7/14/25 08:13, Christoph Hellwig wrote: > On Mon, Jul 14, 2025 at 03:00:57PM +0900, Damien Le Moal wrote: >> Agreed, it would be nice to clean that up. BUT, the chunk_sectors sysfs >> attribute file is reporting the zone size today. Changing that may break >> applications. So I am not sure if we can actually do that, unless the sysfs >> interface is considered as "unstable" ? > > Good point. I don't think it is considered unstable. > Hmm. It does, but really the meaning of 'chunk_sectors' (ie a boundary which I/O requests may not cross) hasn't changed. And that's also the original use-case for the mapping of zone size to chunk_sectors, namely to ensure that the block layer generates valid I/O. So from that standpoint I guess we can change it; in the end, there may (and will) be setups where 'chunk_sectors' is smaller than the zone size. We would need to have another attribute for the zone size, though :-) But arguably we should have that even if we don't follow the above reasoning. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich