On Wed, Feb 21, 2024 at 1:13 PM Jan Engelhardt <jengelh@inai.de> wrote:
On Wednesday 2024-02-21 19:04, Greg Freemyer wrote:
[mkfs.xfs] By default, I get 29 for AGcount and the corresponding AGsize of ~1TB. Supposedly neither are adjustable, but that can't be true during xfs_grow.
My (uninformed) guess is that if I quadruple the size of my xfs filesystem (from 30TB to 120TB), then the number of aggregation groups will also quadruple.
It's adjustable upwards, but not quite downwards. (`xfs_growfs -D ...` apparently only works to the point where the highest-numbered AG has been shrunk to 64 blocks.)
When I use xfs_grow later on, that should allow room for the AGcount to quadruple in count, or AGsize to quadruple in size. One of the 2 has to happen!
Like I said, an increase is not the problem.
As far as I know, xfs_grow doesn't support shrinking the filesystem at all. So increasing the size is the only option.