Hello everybody, There's a note on the wiki that says:
> Note: When you ask Nix to install a package, it will first try to get it in pre-compiled form from a binary cache. By default, Nix will use the binary cache https://cache.nixos.org; it contains binaries for most packages in Nixpkgs. Only if no binary is available in the binary cache, Nix will build the package from source. So if nix-env -i subversion results in Nix building stuff from source, then either the package is not built for your platform by the Nixpkgs build servers, or your version of Nixpkgs is too old or too new. For instance, if you have a very recent checkout of Nixpkgs, then the Nixpkgs build servers may not have had a chance to build everything and upload the resulting binaries to https://cache.nixos.org. The Nixpkgs channel is only updated after all binaries have been uploaded to the cache, so if you stick to the Nixpkgs channel (rather than using a Git checkout of the Nixpkgs tree), you will get binaries for most packages. > http://nixos.org/nix/manual/ Now the last statement says: > The Nixpkgs channel is only updated after all binaries have been uploaded to the cache, so if you stick to the Nixpkgs channel (rather than using a Git checkout of the Nixpkgs tree), you will get binaries for most packages. I am just trying to understand this. If this is true, then why is it that when I sometimes try to install packages, the installation process fails because the upstream URL is not responding. This has happened several times on 15.09 with different kinds of packages like Sage, packages from Freedesktop.org... etc. I understand that there are certain packages that always need to be built from source like the nvidia binary blob. But those above packages shouldn't have problem right? Anyway I'm looking for a way to find what binaries are actually available in the binary cache ahead of time, and compare them between the main channels and the small versions. I've looked around and I can't find anything that actually states the binaries available in small channels versus the main channels. Can anybody clarify this? Thanks, Roger -- Founder of Matrix AI https://matrix.ai/ +61420925975 _______________________________________________ nix-dev mailing list nix-dev@lists.science.uu.nl http://lists.science.uu.nl/mailman/listinfo/nix-dev
