| 28 Oct 2025 |
 vcunat | It's expensive. | 16:59:57 |
| vcunat | Takes more than one hour on Hydra. Part of that is a huge postgresql transaction, but the eval costs are really high. | 17:00:31 |
| vcunat | I think it's OK that some classes of errors don't get caught by CI but only through Hydra/channels. | 17:02:25 |
 emily | yeah, not saying it's easily solvable | 17:03:34 |
| emily | but it would be really nice if it was solved | 17:03:40 |
| emily | has anyone ever looked at if evaluating all the NixOS tests has some specific hot spot? | 17:04:03 |
| emily | is it instantiating a billion Nixpkgs? just the module system being slow? | 17:04:13 |
 K900 | It is both | 17:04:18 |
| K900 | I tried https://github.com/K900/nixpkgs/tree/less-nixpkgses and somehow in our testing on forkos hydra it made things worse | 17:04:38 |
| vcunat | Wolfgang Walther is also looking at it, apparently. | 17:04:39 |
| vcunat | Let's see who's faster 😅 | 17:04:52 |
| K900 | Which makes no fucking sense | 17:04:57 |
| emily | Hydra eval is parallelized with nix-eval-jobs, right? | 17:05:51 |
| emily | is anything shared between the evaluations of multiple NixOS tests? | 17:05:58 |
