[logger] added flush to DiskLogger

[felipemello1]

Context

issue: #1040

What is the purpose of this PR? Is it to

• add a new feature
• fix a bug
• update tests and/or documentation
• other (please add here)

If some part of the pipeline breaks, the logger may not have a chance to flush whats in the buffer. By adding flush after every .log, we can avoid it. A better solution would be to try to gracefully shutdown if something breaks, and then call .flush there, but this should be more complex.

It does increase latency by a few ms, but it shouldn't be a problem if we are only logging a few times per step:

without flush: 0.00066
with flush: 0.0051

Changelog

Just added .flush

Test plan

pytest

• run pre-commit hooks and linters (make sure you've first installed via pre-commit install)
• add unit tests for any new functionality
• update docstrings for any new or updated methods or classes
• run unit tests via pytest tests
• run recipe tests via pytest tests -m integration_test
• manually run any new or modified recipes with sufficient proof of correctness
  • include relevant commands and any other artifacts in this summary (pastes of loss curves, eval results, etc.)

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/torchtune/1078

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

✅ No Failures

As of commit d0473a7 with merge base dceaf05 ():
💚 Looks good so far! There are no failures yet. 💚

This comment was automatically generated by Dr. CI and updates every 15 minutes.