Hi, zimoun <zimon.touto...@gmail.com> skribis:
> On Tue, 27 Oct 2020 at 14:26, Lars-Dominik Braun > <l...@leibniz-psychology.org> wrote: > >> Previously I have been doing this using package-input-rewriting, but starting >> an environment containing python-jupyterlab alone took about 20s (warm >> caches, >> all derivations in the store). Manually rewriting inputs by inheriting and >> alist-delete’ing brings this down to 3s, which is pretty significant. >> --no-grafts has not much of an impact (15s vs 2s) here. See >> https://github.com/guix-science/guix-science/commit/972795a23cc9eb5a0bb1a2ffb5681d151fc4d4b0 >> for the exact changes. > > Is it not related to “#:deep? #t“ by default? The default was #f. Yes, that’s a possible culprit. Try passing #:deep? #f if it works for your use case. Another thing to look at is the <package> object graph (as show by ‘guix graph’). Input rewriting can duplicate parts of the graph, which in turn defeats package->derivation memoization. Just looking at the number of nodes in the graph can give hints. Like Ricardo wrote, it’d be great it you could share a short reproducer. Thanks, Ludo’.
