Remove logic to skip checkpoint save if checkpoint exists

[ashors1]

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test failure

[maanug-nv]

based on current test failure, looks like this requires changes in MCore as well to handle and existing dist ckpt dir. i'd say we should make that change first before merging this

[mikolajblaz]

based on current test failure, looks like this requires changes in MCore as well to handle and existing dist ckpt dir. i'd say we should make that change first before merging this

How can I check the failing tests? The only failing job I see is this one but it doesn't have any useful info: https://github.com/NVIDIA/NeMo/actions/runs/11958751953/job/33339441430?pr=11362

Regardless of the failure, I would recommend ensuring that on the NeMo side the checkpointing logic ensures that we don't save twice to the same directory, otherwise that could lead to silent errors.

We did it for NeMo 1.0 and currently all such circumstances (saving twice to the same dir) are explicitly treated as an error which I believe leads to a better experiments handling from a user perspective

[maanug-nv]

from that link, go to the Summary, and see the 'Failed jobs'. This one is failing.

I would recommend ensuring that on the NeMo side the checkpointing logic ensures that we don't save twice to the same directory, otherwise that could lead to silent errors.

You're right, I completely agree. Currently on main, async save will crash if the dir exists. Non-async save will just print warning and skip saving. Looks like this change is exposing that problem in one of the tests.

What I don't understand is why we aren't running the PTL logic that appends a version counter (1, 2)