| 25 May 2021 |
| nbathum (he or they) set a profile picture. | 14:36:30 |
andi- | In reply to @hexa:lossy.network poked over in #python:nixos.org I did already send him a DM about this... but thanks for getting involved... | 14:40:55 |
| atemu12 joined the room. | 15:46:00 |
andi- | I might have some patches that are similar effective as the --enable-optimisations hammer but aren't hindering reproducibility. The first one is good. Trying the second patch just now but I have to rebootstrap everything for that... | 18:07:26 |
@grahamc:nixos.org | is there something I can do to help? | 18:58:14 |
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 |