Most time is spent on evaluating the derivation (IFD)
Post action uploads are rate limited - does a typical rebuild result in enough uploads?
Seems like magix-nix post action is re-uploading similar store paths on each rerun -> overall build time counts: 3m14s
Are our builds non-deterministic due to IFD?
Another trial of magic-nix which uses the github internal cache as a binary cache for
nix
.Magic nix does not offer out-of-the-box any public cache interaction and we would need to make this work together with cachix. In another exploration, @locallycompact encountered problems by having both enabled: https://github.com/DeterminateSystems/magic-nix-cache/issues/78
However, before tackling this I wondered what the build time improvement would be. This PR contains commits and links to the findings:
magic-nix
orcachix
.accept-flake-config
to seed magic cache from cachix.hydra-node
build with primed cache: https://github.com/cardano-scaling/hydra/actions/runs/10418269282/job/28854308115 -> build step only:1m04s
, overall2m49s
(still uploading)3m14s
Are our builds non-deterministic due to IFD?4m45s
and no pushed paths pushed?4:19s
, also no paths pushed againcachix-action
https://github.com/cardano-scaling/hydra/actions/runs/10419403396 -> rebuild of hydra-node in4m47s
1m28s
,1m50s
1m25s
(accidental cache hit)5m04s
1m39s
hydra-node
was never cached)This write-up is also available on the logbook: https://github.com/cardano-scaling/hydra/wiki/Logbook-2024-H1#2024-08-16