[FIX] Epoch not finished when using `runtime` budget

[ravinkohli]

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• I'm submitting a ...
  • bug report

Issue Description

• When Issue Happens
  When running test_train_pipeline_with_runtime (check test run here), I get ZeroDivisionError: float division by zero at this line.

• Steps To Reproduce

  1. Run test_train_pipeline_with_runtime on reg_cocktail, I think we see the issue there because the default configuration is different and larger than that in development.

Expected Behavior

In case the epoch is not finished and hence N==0, we should raise a warning to the user but exit the function without the error otherwise its wasted func_eval_time even if the configuration performed well.

Current Behavior

When N==0 there is an error which leads to wasted func_eval_time as well as marking a configuration as crashed when it could have been good.

Possible Solution

Check if N==0 and raise a warning rather than the error.

Error message

ZeroDivisionError: float division by zero

Your Local environment

• Operating System: Ubuntu, version: 20.04
• Python, version: 3.8
• Outputs of pip freeze or conda list

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