| 25 May 2021 |
 andi- | Not sure :D | 19:02:57 |
| andi- | I just finished the 2nd commit. Will open an PR now and then there shall be discussion! | 19:03:09 |
| andi- | https://github.com/NixOS/nixpkgs/pull/124416 | 19:14:07 |
| andi- | I might have found one of the sources of PGO builds being non-deterministic: https://github.com/miss-islington/cpython/blob/16270bf2f945eea4c430000d372c30c877523b20/Lib/test/libregrtest/main.py#L259 | 19:42:52 |
| andi- | There is probably still the problem of impure compute happening within the builds (e.g. current time being used for string formatting etc..) | 19:44:03 |
| andi- | mhm that defaults to non-random execution... It could have been so simple :-) | 19:46:07 |
| andi- | Quality hardware. My M1 Mac that I am testing the darwin changes on just restarted. This is the 2nd time in 2 weeks that it dies during an stdenv rebuild.... | 20:30:45 |
| andi- | I am giving up on that architecture... The machine crashes on a single job with 4 cores during the bootstrap... shrug | 20:49:16 |
 baloo | andi: afaict, python was reproducible on >3.6 | 23:07:28 |
| baloo | unless it changed recently | 23:07:40 |
| andi- | In reply to @baloo_:matrix.org
andi: afaict, python was reproducible on >3.6 Well I changed the compile flags in the linked PR ;) | 23:08:15 |
| baloo | pretty sweet | 23:09:14 |
| baloo | that's the thing I had in mind https://www.python.org/dev/peps/pep-0552/ | 23:09:54 |
| baloo | which is a different thing | 23:10:06 |
| baloo | (reproducibility of the .pyc files) | 23:10:15 |
| andi- | Didn't those only have very limited impact on performance anyway? | 23:14:53 |
| baloo | huuum | 23:15:59 |
| baloo | depends on your workflow I'd say | 23:16:22 |
| andi- | Let's say I am running synapse :) | 23:16:41 |
| baloo | it affects the boot performance of python | 23:16:44 |
| baloo | startup performance* | 23:16:53 |
| andi- | So probably only relevant for short-lived processes | 23:19:12 |
| baloo | yeah | 23:19:22 |
| andi- | That don't have a local dir to write cache files to | 23:19:23 |
| baloo | running tests | 23:19:28 |
| baloo | well, iirc a process will try to write to /nix/store/blabla-python/share/foo.pyc if you open the foo.py | 23:20:11 |
| baloo | not sure there is a per-user cache of those | 23:20:30 |
| andi- | Well the cache dir would be more like while developing on python software | 23:20:44 |
| baloo | if it can't store the pyc, it will work just fine, but needs to rebuild | 23:20:49 |
| baloo | yeah but usually you invoke libraries and stuff | 23:21:05 |
