On 19/05/2022 05:19, Damien Le Moal wrote: > On 5/19/22 12:12, Luis Chamberlain wrote: >> On Thu, May 19, 2022 at 12:08:26PM +0900, Damien Le Moal wrote: >>> On 5/18/22 00:34, Theodore Ts'o wrote: >>>> On Tue, May 17, 2022 at 10:10:48AM +0200, Christoph Hellwig wrote: >>>>> I'm a little surprised about all this activity. >>>>> >>>>> I though the conclusion at LSF/MM was that for Linux itself there >>>>> is very little benefit in supporting this scheme. It will massively >>>>> fragment the supported based of devices and applications, while only >>>>> having the benefit of supporting some Samsung legacy devices. >>>> >>>> FWIW, >>>> >>>> That wasn't my impression from that LSF/MM session, but once the >>>> videos become available, folks can decide for themselves. >>> >>> There was no real discussion about zone size constraint on the zone >>> storage BoF. Many discussions happened in the hallway track though. >> >> Right so no direct clear blockers mentioned at all during the BoF. > > Nor any clear OK. So what about creating a device-mapper target, that's taking npo2 drives and makes them po2 drives for the FS layers? It will be very similar code to dm-linear. After all zoned support for FSes started with a device-mapper (dm-zoned) and as the need for a more integrated solution arose, it changed into natiive support. And all that is there is simple arithmetic and a bio_clone(), if this is the slowest part of the stack involving a FS like f2fs or btrfs I'm throwing a round of anyone's favorite beverage at next year's LSFMM. Byte, Johannes
