Re: Docker image sizes

[zimoun]

Hi,


On Fri, 16 Jul 2021 at 22:06, TJ <tj@sheer.tj> wrote:

> I was trying to package a project in docker and to start I did a fairly
> straightforward command:
>
> $ guix pack --format=docker elixir
>
> It generated an image quite a bit larger than I expected.
>
> -r--r--r--    2 root          root      461M Dec 31  1969 
> gfnqg760z22vr8kbvyzdzhs1hc5766c9-elixir-docker-pack.tar.gz

I agree the size is an issue.

> After uncompressing, this is taking 1.5GB and is including quite a few
> unnecessary packages for a minimal image - see below for the top 30.
>
> $ du -s * |sort -g -r | head -n 30
> 155804  g3idjpqsp2p2d163qfzskxj4k58nrx7f-llvm-11.0.0
> 145164  m59c9hj9d4n65maimbpmx2xq56d2mvqs-mesa-20.2.4
> 111708  q233v022vziq8ry18y8q959k110vclvf-webkitgtk-2.32.1
> 110840  cgqj7xswlpvhzxwri3mcqfs1fhbgnka8-erlang-23.2.1
> 103940  qk5v5vzwfl066zch67nxlv4x7aspf0fx-samba-4.13.4
> 93972   cw8brvxkzp4kmdqldsv1wkvi2cv4kq4x-python-3.8.2
> 64620   8zvc5mvk0xm3ygrxsgpyy5ilxb5rzjry-perl-5.30.2
> 56300   18hp7flyb3yid3yp49i6qcdq0sbi5l1n-guile-3.0.2
> 52748   nscar35x261xky08qih2ddxq1b105qwd-gtk+-3.24.24
> 41092   fa6wj5bxkj5ll1d7292a70knmyl7a0cr-glibc-2.31
> 39544   2wqjj3mkqdvsvksndr2hpjpi7qqwi7kr-icu4c-66.1
> 35848   fi1mdh30b5q6zvplvayn68lb575xcd1k-ghostscript-with-cups-9.52
> 34768   01b4w3m6mp55y531kyi1g8shh722kwqm-gcc-7.5.0-lib
> 34188   wjmydimw608k61qxmsifkam11jwgpric-wxwidgets-3.0.5.1
> 24224   jv6v8p8jbjf6hpscgp3dgdfylrdhldi1-gdk-pixbuf+svg-2.40.0
> 18488   n8awazyldv9hbzb7pjcw76hiifmvrpvd-coreutils-8.32
> 18464   57xj5gcy1jbl9ai2lnrqnpr0dald9i65-coreutils-8.32
> 16596   jsqxxnaj5p8a22mrsvl679gi7jl26z4j-glib-2.62.6
> 16400   aza259fsrb841zwb4rjzfzs2nrsf28f1-eudev-3.2.9
> 16060   9z185s19zp2p9yq8gdayxgibaphxfcps-cups-2.3.3
> 15604   4l2il4wcxjb443xwc2arwixpq28pbfvl-cups-minimal-2.3.3
> 14140   02z5vgdhgxw4gcjvhx51mvy1ax4lzxmp-fftwf-3.3.8
> 13912   zzkly5rbfvahwqgcs7crz0ilpi7x5g5p-ncurses-6.2
> 13096   lv92cmzqjpb8mxygpqdvh0mkkkfi9vmz-libxcb-1.14
> 10876   n3pjsbpd51x6vqikfglmrdbijflammf6-gst-plugins-base-1.18.2
> 10588   sayvymkqjl328rsivzlp9r46337rvdmz-pulseaudio-14.0
> 10084   7y3lvk3xf4im8n44337mc6y0ccysvfia-font-dejavu-2.37
> 9888    hr1p9l1waam8lk2csdwbzaipf14h9n33-gstreamer-1.18.2
> 9576    a45p39mgqvfd8kjwibyr0q42k1mw7gmf-util-linux-2.35.1-lib
> 8812    z3vbqvpgcz7lag9qci074hjry4j3120i-shared-mime-info-1.15
>
> I wouldn't expect to need llvm, mesa, webkit, samba, python, perl,
> gtk, cups, pulseaudio, etc, etc. in a production image.

You can use the option ’--path’ to find out why elixir depends on
unexpected packages, for instance:

        $ guix graph --path elixir samba        
        elixir@1.12.0
        erlang@24.0.2
        wxwidgets@3.0.5.1
        webkitgtk@2.32.3
        libsoup@2.72.0
        samba@4.13.1


> What would be the recommended way to minimize the derivation?

Examine each and try to spot what could be cut.  For instance, ’erlang’
depends on ’wxwidgets’ which brings a lot of stuff.

Hope that helps,
simon