Dovecot v2.3.13 reporting (very) incorrect vsize for some maildir folders

[Eirik Rye]

> On 20 May 2021, at 15:18, Eirik Rye <rye at trojka.no> wrote:
> 
> I assume there are some sparseness or block size related shenanigans going on here instead, causing differences in reported physical usage by `du` (syscall `newfstatat()`) compared to `ls` (syscall `lstat()`) and dovecot.
> 
> The filesystem quota system in Linux, which is what we're migrating from, apparently uses the same calculation method as `du`, which adds to the confusion.

Oh, a lot of messages in these folders appear to be hardlinks to the same inodes (duplicates). Dovecot's vsize-calculation doesn't care that messages are referencing the same inodes, but `du` and Linux' quota calculation obviously does.

That explains everything, then. Apologies again for the bother.

- Eirik