🐞 bug report

Affected Rule

py_binary and py_test

Is this a regression?

No

Description

Hermetic toolchains incur a significant overhead to executing Python targets due to the large amount of files which are added to the runfiles tree.
You find an analysis of the issue here: https://github.com/martis42/show_hermetic_python_overhead

Bazel caching of course negates much of this issue in daily working.
Still, whenever a test has to rerun we pay this additional overhead.

I don't know if there is a "perfect" solution possible given how Bazel sandboxing works.
However, it would be great if rues_python would add a note in its documentation for hermetic toolchains that adding --nolegacy_external_runfiles to the .bazelrc file is recommended.

Maybe the rules_python maintainer can even convince the Bazel maintainer to prioritize working on flipping --legacy_external_runfiles in Bazel 8 ?

🔬 Minimal Reproduction

You see reproduce this with this small example workspace https://github.com/martis42/show_hermetic_python_overhead

🔥 Exception or Error

NA

🌍 Your Environment

Operating System:

  
Linux Mint 21.1
  

Output of bazel version:

  
Bazelisk version: v1.16.0
Build label: 7.0.0
Build target: @@//src/main/java/com/google/devtools/build/lib/bazel:BazelServer
Build time: Mon Dec 11 16:51:49 2023 (1702313509)
Build timestamp: 1702313509
Build timestamp as int: 1702313509
  

Rules_python version:

  
0.27.0
  

Anything else relevant?

#1624 might be related.
It is however maybe Windows specific.