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    SubjectRe: Please further explain Linux's "zoned storage" roadmap [was: Re: [PATCH v14 00/13] support zoned block devices with non-power-of-2 zone sizes]
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    Thanks a lot Damien for the summary. Your feedback has made this series
    much better.

    > Pankaj patch series is all about supporting ZNS devices that have a zone
    > size that is not a power of 2 number of LBAs as some vendors want to
    > produce such drives. There is no such move happening in the SMR world as
    > all users are happy with the current zone sizes which match the kernel
    > support (which currently requires power-of-2 number of LBAs for the zone
    > size).
    >
    > I do not think we have yet reached a consensus on if we really want to
    > accept any zone size for zoned storage. I personally am not a big fan of
    > removing the existing constraint as that makes the code somewhat heavier
    > (multiplication & divisions instead of bit shifts) without introducing any
    > benefit to the user that I can see (or agree with). And there is also a
    > risk of forcing onto the users to redesign/change their code to support
    > different devices in the same system. That is never nice to fragment
    > support like this for the same device class. This is why several people,
    > including me, requested something like dm-po2zoned, to avoid breaking user
    > applications if non-power-of-2 zone size drives support is merged. Better
    > than nothing for sure, but not ideal either. That is only my opinion.
    > There are different opinions out there.

    I appreciate that you have explained the different perspectives. We have
    covered this written and orally, and it seems to me that we have a good
    coverage of the arguments in the list.

    At this point, I would like to ask the opinion of Jens, Christoph and
    Keith. Do you think we are missing anything in the series? Can this be
    queued up for 6.1 (after I send the next version with a minor fix suggested
    by Mike)?

    --
    Regards,
    Pankaj

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