fix the asr infernece model, paddle.no_grad, test=doc

paddlespeech/server/engine/asr/online/asr_engine.py

@@ -356,6 +356,7 @@ class PaddleASRConnectionHanddler:
         else:
             raise Exception("invalid model name")
 
+    @paddle.no_grad()
     def decode_one_chunk(self, x_chunk, x_chunk_lens):
         logger.info("start to decoce one chunk with deepspeech2 model")
         input_names = self.am_predictor.get_input_names()
@@ -397,6 +398,7 @@ class PaddleASRConnectionHanddler:
         logger.info(f"decode one best result: {trans_best[0]}")
         return trans_best[0]
 
+    @paddle.no_grad()
     def advance_decoding(self, is_finished=False):
         logger.info("start to decode with advanced_decoding method")
         cfg = self.ctc_decode_config
@@ -503,6 +505,7 @@ class PaddleASRConnectionHanddler:
         else:
             return ''
 
+    @paddle.no_grad()
     def rescoring(self):
         if "deepspeech2online" in self.model_type or "deepspeech2offline" in self.model_type:
             return

paddlespeech/server/engine/asr/online/ctc_search.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 from collections import defaultdict
-
+import paddle
 from paddlespeech.cli.log import logger
 from paddlespeech.s2t.utils.utility import log_add
 
@@ -29,6 +29,7 @@ class CTCPrefixBeamSearch:
         self.config = config
         self.reset()
 
+    @paddle.no_grad()
     def search(self, ctc_probs, device, blank_id=0):
         """ctc prefix beam search method decode a chunk feature