[BugFix] Fix modification of sky/__init__.py when building sky wheels

[cblmemo]

To reproduce:

python -c 'from sky.backends import wheel_utils; wheel_utils.build_sky_wheel()'

This will replace the _SKYPILOT_COMMIT_SHA in sky/__init__.py with the current commit. This PR fixed the problem.

Tested (run the relevant ones):

• Code formatting: bash format.sh
• Any manual or new tests for this PR (please specify below)
• All smoke tests: pytest tests/test_smoke.py
• Relevant individual smoke tests: pytest tests/test_smoke.py::test_fill_in_the_name
• Backward compatibility tests: bash tests/backward_comaptibility_tests.sh

[Michaelvll]

Ahh, nice catch @cblmemo! I was trying to only modify the __init__ file in the tmpdir, to avoid race condition for multiple builds but it seems we are doing symlink for the folder, so it will reflect to the original skypilot codebase. Is there a way we can only update the __init__ file, e.g., we symlink all the other files/folders, but copy the __init__.py and change it?

[cblmemo]

Ahh, nice catch @cblmemo! I was trying to only modify the __init__ file in the tmpdir, to avoid race condition for multiple builds but it seems we are doing symlink for the folder, so it will reflect to the original skypilot codebase. Is there a way we can only update the __init__ file, e.g., we symlink all the other files/folders, but copy the __init__.py and change it?

Done 🫡

[Michaelvll]

Thanks for the quick fix @cblmemo! Could we quickly test the speed for building the wheel with and without this PR? I suppose there won't be much difference. : )

[cblmemo]

Thanks for the quick fix @cblmemo! Could we quickly test the speed for building the wheel with and without this PR? I suppose there won't be much difference. : )

It even became faster 🤣 Though it should be some irrelevant reasons

w/ this PR: Average at 2.029663157463074

Original data: 10 times
[2.0189316272735596, 1.9405455589294434, 2.0807836055755615, 2.0257434844970703, 2.1302366256713867, 2.126328945159912, 1.9333207607269287, 2.0329902172088623, 1.971566915512085, 2.0361838340759277]

w/o this PR: Average at 2.0818066596984863

Original data: 10 times
[2.3937103748321533, 1.940063238143921, 1.9440243244171143, 2.032553195953369, 2.0736310482025146, 2.0780720710754395, 2.1743052005767822, 2.1686527729034424, 2.0339012145996094, 1.9791531562805176]

Test script:

from sky.backends import wheel_utils
import shutil,time

ts = []

for _ in range(10):
    st = time.time()
    shutil.rmtree(wheel_utils.WHEEL_DIR, ignore_errors=True)
    wheel_utils.build_sky_wheel()
    ed = time.time()
    ts.append(ed - st)


print(ts)
print(sum(ts) / len(ts))

[cblmemo]

Just found out that I left the shutil.rmtree inside the timer... Now it looks like the following and the result is the same as the previous one.

from sky.backends import wheel_utils
import shutil, time

ts = []

for _ in range(10):
    shutil.rmtree(wheel_utils.WHEEL_DIR, ignore_errors=True)
    st = time.time()
    wheel_utils.build_sky_wheel()
    ed = time.time()
    ts.append(ed - st)


print(ts)
print(sum(ts) / len(ts))

w/ this PR: Average at 2.0500237226486204

Original data: 10 times
[2.0702223777770996, 2.0205273628234863, 2.078216552734375, 2.1142842769622803, 1.9742474555969238, 2.0165488719940186, 1.971510648727417, 2.0825717449188232, 2.09531569480896, 2.0767922401428223]

w/o this PR: Average at 2.0342708349227907

Original data: 10 times
[2.1428840160369873, 2.0071356296539307, 1.9189136028289795, 2.035106897354126, 2.030364513397217, 2.0747296810150146, 2.0613133907318115, 1.944849967956543, 2.071007013320923, 2.056403636932373]