Re: "guix system reconfigure" downloads 2G of stuff it doesn't need

[Marek Paśnikowski]

Felix Lechner via <help-guix@gnu.org> writes:

> Hi Leo,
>
> On Thu, Aug 01 2024, Leo Famulari wrote:
>
>>> [...] and, equally importantly, why they are _not_ considered
>>> necessary by "guix gc"?
>>
>> The short answer is "to save disk space at the potential cost of
>> increased network usage".
>
> I am not sure I agree with your framing.  While adjustments to the
> garbage collector may prevent downloads, I believe some prerequisites
> are undeclared (although I cannot say which ones or why).
>

That is indeed the case. I have a bash alias which combines "guix pull",
"guix system reconfigure" and "guix gc" with options. Every single time
I update the system with this alias, I see "ghostscript-with-x", "ibus",
"ruby" and others being fetched before anything else. I do have both
--gc-keep* options enabled.

>> you can run the guix-daemon with the argument "--gc-keep-outputs=yes",
>> and maybe also "--gc-keep-derivations=yes":
>
> I have been doing that, but in my estimation what is being kept exceeds
> what's needed by a wide degree.
>

Are you perhaps not aware of "guix home delete-generations -d *" and
"sudo guix system delete-generations -d *"? I used to have my system
partition overfilled with /gnu/store data before I found those
commands. Once I issued them, the next "guix gc" cleared over 100GiB.