checkpoint model on first step callback (#2906)

* checkpoint model on first step callback

* remove debug

* add test cases; update existing tests not to save on first step

* move test out of solo

* delete

* default to False

* typo

tests/e2e/multigpu/solo/test_flex.py

@@ -61,6 +61,7 @@ class TestPackedFlex:
                 "max_steps": 2,
                 "use_tensorboard": True,
                 "save_strategy": "no",
+                "save_first_step": False,
             }
         )
         if is_torch_bf16_gpu_available():

tests/e2e/multigpu/solo/test_grpo.py

@@ -223,6 +223,7 @@ def oai_gsm8k_transform(cfg, *args, **kwargs):
                 "save_safetensors": True,
                 "bf16": "auto",
                 "use_tensorboard": True,
+                "save_first_step": False,
             }
         )
 
@@ -317,6 +318,7 @@ def oai_gsm8k_transform(cfg, *args, **kwargs):
                 "save_safetensors": True,
                 "bf16": "auto",
                 "use_tensorboard": True,
+                "save_first_step": False,
             }
         )
 
@@ -409,6 +411,7 @@ def oai_gsm8k_transform(cfg, *args, **kwargs):
                 "save_safetensors": True,
                 "bf16": "auto",
                 "use_tensorboard": True,
+                "save_first_step": False,
             }
         )