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Wong" Cc: linux-xfs@vger.kernel.org, ritesh.list@gmail.com, ojaswin@linux.ibm.com, bfoster@redhat.com, david@fromorbit.com, hsiangkao@linux.alibaba.com References: <20251022160532.GM3356773@frogsfrogsfrogs> From: "Nirjhar Roy (IBM)" In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/23/25 12:04, Christoph Hellwig wrote: > On Wed, Oct 22, 2025 at 09:05:32AM -0700, Darrick J. Wong wrote: >>> I'm still missing what the overall plan is here. For "normal" XFS >>> setups you'll always have inodes that we can't migrate. Do you plan >>> to use this with inode32 only? >> ...or resurrect xfs_reno? > That only brings up some vague memories. But anything in userspace > would not be transactional safe anyway. > >> Data/attr extent migration might not be too hard if we can repurpose >> xfs_zonegc for relocations. > The zonegc code is very heavily dependent on not having to deal with > freespace fragmentation for writes, so I don't think the code is > directly reusable. But the overall idea applies, yes. > >> I think moving inodes is going to be very >> very difficult because there's no way to atomically update all the >> parents. >> >> (Not to mention whatever happens when the inumber abruptly changes) > Yes. That's my big issues with all the shrink plans, what are we > going to do about inodes? Hi Christoph and Darrick, Sorry for the delayed response. So, my initial plan was to get the the shrink work only for empty AGs for now (since we already have the last AG partial shrink merged). Do you think this will be helpful for users? Regarding the data/inode movement, can you please give me some ideas/pointers as to how can we move the inodes. I can in parallel start exploring those areas and work incrementally. --NR -- Nirjhar Roy Linux Kernel Developer IBM, Bangalore