Extend HE-Lora test with Z3 support + Fix/add guard in HE for Z3 (#3883)

* extend the test and fix fp16 typo.

* guard reset params with z3 enabled check.

---------
Co-authored-by: NOlatunji Ruwase <olruwase@microsoft.com>

deepspeed/runtime/hybrid_engine.py

@@ -431,8 +431,9 @@ class DeepSpeedHybridEngine(DeepSpeedEngine):
         super().step(lr_kwargs=lr_kwargs)
 
         if len(self._inference_containers) > 0:
-            for inference_container in self._inference_containers:
-                inference_container.reset_params()
+            if not self.Z3_enabled:
+                for inference_container in self._inference_containers:
+                    inference_container.reset_params()
 
         if self._training_start_time is not None:
             self._training_latency += (time.time() - self._training_start_time)

tests/unit/hybrid_engine/test_he_lora.py

@@ -9,8 +9,8 @@ import torch
 import torch.nn.functional as F
 import pytest
 import deepspeed
+from deepspeed.runtime.zero import GatheredParameters
 from deepspeed.ops.op_builder import OpBuilder
-from deepspeed.ops.adam import FusedAdam
 from deepspeed.utils import safe_get_full_grad
 import numpy.testing as npt
 from unit.common import DistributedTest
@@ -109,7 +109,9 @@ def only_optimize_lora_parameters(model):
 
 @pytest.mark.seq_inference
 @pytest.mark.parametrize("batch_size", [1], ids=["bsz=1"])
+@pytest.mark.parametrize("zero_stage", [2, 3], ids=["zero_stage=2", "zero_stage=3"])
 @pytest.mark.parametrize("model_name", ["EleutherAI/gpt-neo-125m", "facebook/opt-350m", "bigscience/bloom-560m"])
+@pytest.mark.parametrize("offload_device", ["none", "cpu"])
 class TestHybridEngineLoRA(DistributedTest):
     world_size = 1
 
@@ -139,9 +141,8 @@ class TestHybridEngineLoRA(DistributedTest):
         else:
             raise NotImplementedError(f"batch_size {batch_size} not implemented")
 
-    def test_lora(self, batch_size, model_name):
+    def test_lora(self, batch_size, model_name, zero_stage, offload_device):
         local_rank = int(os.getenv("LOCAL_RANK", "0"))
-
         model = self.get_model(model_name)
         tokenizer = self.get_tokenizer(model_name)
         train_sentences = self.get_train_sentences(batch_size)
@@ -149,10 +150,33 @@ class TestHybridEngineLoRA(DistributedTest):
         # Inject LoRA
         model = convert_linear_layer_to_lora(model, "", 8)
         model = only_optimize_lora_parameters(model)
-        optim = FusedAdam([p for p in model.parameters() if p.requires_grad], lr=1.0, betas=(0.9, 0.95))
-        ds_config = {"train_batch_size": batch_size, "bfp16": {"enabled": True}, "hybrid_engine": {"enabled": True}}
 
-        model, *_ = deepspeed.initialize(model=model, optimizer=optim, config=ds_config)
+        ds_config = {
+            "optimizer": {
+                "type": "Adam",
+                "params": {
+                    "lr": 1.0,
+                    "betas": [0.9, 0.95]
+                }
+            },
+            "train_batch_size": batch_size,
+            "fp16": {
+                "enabled": True,
+                "initial_scale_power": 12
+            },
+            "hybrid_engine": {
+                "enabled": True,
+                "pin_parameters": True
+            },
+            "zero_optimization": {
+                "stage": zero_stage,
+                "offload_optimizer": {
+                    "device": offload_device
+                }
+            }
+        }
+
+        model, *_ = deepspeed.initialize(model=model, config=ds_config)
 
         # Verify gradient norm is larger than 0
         before_grad_update_layer0_params = [
@@ -187,7 +211,9 @@ class TestHybridEngineLoRA(DistributedTest):
 
         # Verify fuse will mutate layer_params
         model.eval()
-        model.fuse_lora_weight()
+        with GatheredParameters(model.parameters()):
+            model.fuse_lora_weight()
+
         after_grad_update_layer0_params_lora_fused = [
             ele.detach().cpu().float().numpy() for ele in model.layer_params[0]
             if ele is not None and len(ele.shape) > 1
@@ -196,4 +222,6 @@ class TestHybridEngineLoRA(DistributedTest):
         for lhs, rhs in zip(before_grad_update_layer0_params, after_grad_update_layer0_params_lora_fused):
             with pytest.raises(AssertionError):
                 npt.assert_allclose(lhs, rhs, 1E-5, 1E-5)
-        model.unfuse_lora_weight()
+
+        with GatheredParameters(model.parameters()):
+            model.unfuse_lora_weight()