On 2022-05-04 23:14, David Sterba wrote: >> This commit: `btrfs: zoned: relax the alignment constraint for zoned >> devices` makes sure the zone size is BTRFS_STRIPE_LEN aligned (64K). So >> even the npo2 zoned device should be aligned to `fs_info->sectorsize`, >> which is typically 4k. >> >> This was one of the comment that came from David Sterba: >> https://lore.kernel.org/all/20220315142740.GU12643@xxxxxxxxxxxxx/ >> where he suggested to have some sane alignment for the zone sizes. > > My idea of 'sane' value would be 1M, that we have 4K for sectors is > because of the 1:1 mapping to pages, but RAM sizes are on a different > scale than storage devices. The 4K is absolute minimum but if the page > size is taken as a basic constraint, ARM has 64K and there are some 256K > arches. That is a good point. I think it is safe to have 1MB as the minimum alignment so that it covers all architecture's page sizes. Thanks. I will queue this up.
