Confusion about NeptuneLogger.save_dir implementation

[daniellepintz]

In the docstring it says the save_dir is None, but then why does it return a path? Should we change either the docstring, or the implementation here?

https://github.com/PyTorchLightning/pytorch-lightning/blob/9d8faecdb2b873b52b95f2772f4bf48068a0af9a/pytorch_lightning/loggers/neptune.py#L516-L524

[daniellepintz]

Any insights on this @awaelchli @edward-io @Borda @rohitgr7?

[rohitgr7]

I haven't tried Neptune. Can you try running it in online and offline modes and see where it saves the logs. I also remember Neptune doesn't allow configuring the save_dir. If it saves inside .neptune all the time, then docstrings can be updated.

[daniellepintz]

My understanding from reading the code is that Neptune doesn't have an offline mode: https://github.com/PyTorchLightning/pytorch-lightning/blob/master/pytorch_lightning/loggers/neptune.py

[awaelchli]

It would be best to ask the neptune team directly @kamil-kaczmarek @Raalsky @Blaizzy
Neptune doesn't log anything to a local directory so save_dir there doesn't make much sense, so I guess at the time of implementation, the best other option was to point at the ".neptune" folder.

[Blaizzy]

Most welcome!

Feel free to reach out if you have any further questions. I would be happy to help👍🏽

[Blaizzy]

Hi @daniellepintz

I hope you are well,

If the answer I gave you satisfies you, do you mind marking it as the answer so others in the community with the same doubt can easily find it? 👍 😃

[daniellepintz]

of course!

[daniellepintz]

Actually it doesn't seem that is possible since it is not top-level. Feel free to make a new top level comment and I will do so

[Blaizzy]

Thank you, I didn't know that.
No worries, a new top-level comment is done ✅ 😊
#11766 (comment)

[Blaizzy]

Hi @daniellepintz

Prince Canuma here, a Data Scientist at Neptune.ai

I will let the engineering team know about this,

By default, Neptune will create a '.neptune' folder inside the current working directory. In the case of #6867 it changes the model checkpoint path to be '.neptune' folder in case the user doesn't define his own path using ModelCheckpointCallback() for example.
Check this commit: 5ac80ec

But still, a bit confused because I thought Neptune doesn't save anything locally.

Neptune uses the '.neptune' folder to store metadata temporarily. For example, you track a run in offline mode or there is a network connectivity issue in which case neptune also automatically switches to offline mode and save the data to disk. Later you can synchronize the locally stored metadata with the servers using the neptune sync CLI command.

Docs:

https://docs.neptune.ai/api-reference/command-line-interface#neptune
https://docs.neptune.ai/api-reference/command-line-interface#neptune-sync