Hi, zimoun skribis: > 1) around 25 seconds added to "guix pull"... but I am more than often > waiting around 10 minutes when pulling. > 2) the speedup is clear: more than 2x. Nice! It does seem like Arun’s v3 (or maybe even v2) would work nicely. > The question is the tradeoff between: the slowdown of pull vs the > speedup of search. What is acceptable? That’s only one criterion among others. I hear the argument that 25s is “nothing” compared to the rest, but it’s really a tradeoff. Like, if I spent a day optimizing ‘guix pull’ and managed to save 25s, I would find it nice. :-) > $ time guix pull -C ~/.config/guix/default-channels.scm It also depends on what’s in that file, of course. > Then, if I pull back from 8cf6d15 to '--commit=a357849f5b' then it takes: > > real 2m13.693s > user 1m37.418s > sys 0m0.666s For me: --8<---------------cut here---------------start------------->8--- $ guix describe Generacio 139 Apr 13 2020 21:50:08 (nuna) guix bad368b repository URL: https://git.savannah.gnu.org/git/guix.git branch: master commit: bad368b0d794689f3a8a11b58f1ea4987938682e $ time guix pull -p /tmp/test --commit=bad368b0d794689f3a8a11b58f1ea4987938682e Updating channel 'guix' from Git repository at 'https://git.savannah.gnu.org/git/guix.git'... Building from this channel: guix https://git.savannah.gnu.org/git/guix.git bad368b [...] real 0m57.916s user 1m1.017s sys 0m0.609s --8<---------------cut here---------------end--------------->8--- (On a 2.6 GHz i7 though.) > Well, let remove the profiles and garbage collect the index files: > > rm /tmp/default /tmp/v{2,3}* > guix gc -D \ > /gnu/store/g5c08vqsv31nkn2r0hr32dbrkhf3cvd8-guix-package-cache \ > /gnu/store/8xbzhn81hmshagbgazmnr7xfps1cdsa3-guix-package-search-index \ > /gnu/store/8j78b5c4ddic21gcx7wpbq2akjn7x7mr-guix-package-metadata-cache Could you do, for v2 and v3: time guix build /gnu/store/…-package-metadata-cache.drv --check ? That we’ll give us the exact cost of that part. It’ll be interesting especially in the Xapian case, which we expected to be higher. Thanks for the insightful benchmarks! Ludo’.