Re: Are 'guix gc' stats exaggerated?

[Andreas Enge <andreas@enge.fr>]

Am Sun, Jun 09, 2024 at 12:19:55PM +0300 schrieb Efraim Flashner:
> In my not having looked at the code, I'll point out that running `guix
> gc -C 10G` will clear 10G of items from the store, but will return
> between 2-10G of real space for future use on the hard drive.  Thinking
> across my various machines, on my desktop and laptop using btrfs this is
> the case, but on my other machines using ext4 I think the space cleared
> and what I'm expecting to have free to use do actually match up, but I
> don't remember paying that much attention to the numbers previously on
> those machines.

In my experience on ext4 (also not backed by looking at the code), "guix gc"
always deletes substantially less than what I ask for. I always thought it
just counted hard linked files even when the link count does not go to 0
and the file is not actually deleted.

For instance, I have tried it just now:
$ df -h .
/dev/mapper/cryptroot  468G    427G   18G   97% /

$ guix gc -F 20G
guix gc: 2.931,84 MiB werden freigegeben
...
deleted or invalidated more than 3074252800 bytes; stopping

$ df -h .
/dev/mapper/cryptroot  468G    427G   18G   96% /

Andreas