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verified publisher icon DeterminateSystems

Caching already cached artifacts

Open eureka-cpu opened this issue 5 months ago • 3 comments

I noticed on my second run, after not changing any of the dependencies of my build I'm seeing some pretty long wait times for caching artifacts, which you'd think wouldn't happen since they were already cached on the previous run: https://github.com/Cloud-Scythe-Labs/cargo-reaper/actions/runs/15789495198/job/44512677100?pr=24

eureka-cpu avatar Jun 20 '25 23:06 eureka-cpu

In the case linked above, it took 34mins for the magic nix cache step to complete, the previous run took ~8mins: https://github.com/Cloud-Scythe-Labs/cargo-reaper/actions/runs/15789299694/job/44512155113

eureka-cpu avatar Jun 21 '25 00:06 eureka-cpu

Similarly for my project (using @main today so I guess e994df02ed5d8f24f35a02bc566bf7c5de89a9d9 )

  • Without the cache, my nix build takes about 12 minutes.
  • After enabling the cache, the nix build step takes 12 minutes, then 4 minutes for "Post Run the Magic Nix Cache".
  • Then on the second build after enabling cache, the nix build step takes 12 minutes, then 10 minutes for "Post Run the Magic Nix Cache".

unhammer avatar Jul 15 '25 18:07 unhammer

Yep, noticed it just seems to always cache new things even when there aren't any changes that should have made that necessary @grahamc

eureka-cpu avatar Jul 16 '25 20:07 eureka-cpu