[eagle2] fix end check when target model verify (#2723)

python/sglang/srt/speculative/eagle_utils.py

@@ -550,8 +550,37 @@ class EagleVerifyInput(SpecInfo):
             triton.next_power_of_2(max_draft_len),
         )
 
-        accept_index = accept_index[accept_index != -1]
+        draft_input = EAGLEDraftInput()
+        new_accept_index = []
+        unfinished_index = []
+        finished_extend_len = {}  # {rid:accept_length + 1}
+        accept_index_cpu = accept_index.tolist()
+        predict_cpu = predict.tolist()
+        # iterate every accepted token and check if req has finished after append the token
+        # should be checked BEFORE free kv cache slots
+        for i, (req, accept_index_row) in enumerate(zip(batch.reqs, accept_index_cpu)):
+            new_accept_index_ = []
+            for j, idx in enumerate(accept_index_row):
+                if idx == -1:
+                    break
+                id = predict_cpu[idx]
+                # if not found_finished:
+                req.output_ids.append(id)
+                finished_extend_len[req.rid] = j + 1
+                req.check_finished()
+                if req.finished():
+                    draft_input.has_finished = True
+                    # set all tokens after finished token to -1 and break
+                    accept_index[i, j + 1 :] = -1
+                    break
+                else:
+                    new_accept_index_.append(idx)
+            if not req.finished():
+                new_accept_index.extend(new_accept_index_)
+                unfinished_index.append(i)
+        accept_length = (accept_index != -1).sum(dim=1) - 1
 
+        accept_index = accept_index[accept_index != -1]
         accept_length_cpu = accept_length.tolist()
         verified_id = predict[accept_index]
         verified_id_cpu = verified_id.tolist()
@@ -570,26 +599,9 @@ class EagleVerifyInput(SpecInfo):
             triton.next_power_of_2(bs),
         )
         batch.seq_lens.add_(accept_length + 1)
-        new_accept_index = []
-        unfinished_index = []
-        finished_extend_len = {}  # {rid:accept_length + 1}
-        # retracted_reqs, new_token_ratio = batch.retract_decode()
-
-        low = 0
-        draft_input = EAGLEDraftInput()
-        for i, (req, verified_len) in enumerate(zip(batch.reqs, accept_length_cpu)):
-            req.output_ids.extend(verified_id_cpu[low : low + verified_len + 1])
-            req.check_finished()
-            if req.finished():
-                draft_input.has_finished = True
-            else:
-                new_accept_index.append(accept_index[low : low + verified_len + 1])
-                unfinished_index.append(i)
-            low += verified_len + 1
-            finished_extend_len[req.rid] = verified_len + 1
 
         if len(new_accept_index) > 0:
-            new_accept_index = torch.cat(new_accept_index, dim=0)
+            new_accept_index = torch.tensor(new_accept_index, device="cuda")
             draft_input.verified_id = predict[new_accept_index]
             draft_input.hidden_states = batch.spec_info.hidden_states[new_accept_index]
             draft_input.accept_length = accept_length[unfinished_index]

test/srt/test_eagle_infer.py

@@ -1,5 +1,7 @@
 import unittest
 
+from transformers import AutoConfig, AutoTokenizer
+
 import sglang as sgl
 
 
@@ -34,6 +36,33 @@ class TestEAGLEEngine(unittest.TestCase):
         print(out2)
         self.assertEqual(out1, out2)
 
+    def test_eagle_end_check(self):
+        prompt = "[INST] <<SYS>>\\nYou are a helpful assistant.\\n<</SYS>>\\nToday is a sunny day and I like [/INST]"
+        target_model_path = "meta-llama/Llama-2-7b-chat-hf"
+        tokenizer = AutoTokenizer.from_pretrained(target_model_path)
+        speculative_draft_model_path = "lmzheng/sglang-EAGLE-llama2-chat-7B"
+
+        sampling_params = {
+            "temperature": 0,
+            "max_new_tokens": 1024,
+            "skip_special_tokens": False,
+        }
+
+        engine = sgl.Engine(
+            model_path=target_model_path,
+            speculative_draft_model_path=speculative_draft_model_path,
+            speculative_algorithm="EAGLE",
+            speculative_num_steps=3,
+            speculative_eagle_topk=4,
+            speculative_num_draft_tokens=16,
+        )
+        out1 = engine.generate(prompt, sampling_params)["text"]
+        engine.shutdown()
+        print("==== Answer 1 ====")
+        print(repr(out1))
+        tokens = tokenizer.encode(out1, truncation=False)
+        assert tokenizer.eos_token_id not in tokens
+
 
 if __name__ == "__main__":
     unittest.main()