[Feature] Support repetition early stop (#3024)

* support repetition early stop and support user to set the parameter

* remove log

* fix codestyle

* add the early_stop_config to rollout_config

* update config and EarlyStopper class

* fix the bug for triton

* modify the stop method

* update description

* modify the usage for stop_flags

---------

Co-authored-by: Yuanle Liu <yuanlehome@163.com>

fastdeploy/config.py

@@ -567,6 +567,74 @@ class GraphOptimizationConfig:
             argument = self.use_cudagraph
 
 
+class EarlyStopConfig:
+    def __init__(
+        self,
+        args,
+    ):
+        """
+        Early Stop Configuration class.
+
+        Attributes:
+            window_size: size of the window
+            threshold: trigger early stop when the ratio of probs exceeds the threshold
+        """
+        """enable to use early stop"""
+        self.enable_early_stop: bool = False
+        """strategy for early stop, the strategy lists are ['repetition']"""
+        self.strategy: str = "repetition"
+        """ the maximum length of verify window for early stop """
+        self.window_size: int = 3000
+        """ the probs threshold for early stop """
+        self.threshold: float = 0.99
+
+        if args is not None:
+            for key, value in args.items():
+                if hasattr(self, key):
+                    setattr(self, key, value)
+        self.check_legality_parameters()
+
+    def to_json_string(self):
+        """
+        Convert early_stop_config to json string.
+        """
+        return json.dumps({key: value for key, value in self.__dict__.items()})
+
+    def __str__(self) -> str:
+        return self.to_json_string()
+
+    def check_legality_parameters(
+        self,
+    ) -> None:
+        """Check the legality of parameters passed in from the command line"""
+        if self.enable_early_stop is not None:
+            assert isinstance(
+                self.enable_early_stop, bool
+            ), "In early stop config, type of enable_early_stop must is bool."
+        if self.window_size is not None:
+            assert isinstance(self.window_size, int), "In early stop config, type of window_size must be int."
+            assert self.window_size > 0, "window_size must large than 0"
+        if self.threshold is not None:
+            assert isinstance(self.threshold, float), "In early stop config, type of threshold must be float."
+            assert self.threshold >= 0 and self.threshold <= 1, "threshold must between 0 and 1"
+
+    def update_enable_early_stop(self, argument: bool):
+        """
+        Unified user specifies the enable_early_stop parameter through two methods,
+        '--enable-early-stop' and '--early-stop-config'
+        """
+        if self.enable_early_stop is None:
+            # User only set '--enable-early-stop'
+            self.enable_early_stop = argument
+        else:
+            # User both set '--enable-early-stop' and '--early-stop-config'
+            if self.enable_early_stop is False and argument is True:
+                raise ValueError(
+                    "Invalid parameter: Cannot set ---enable-early-stop and --early-stop-config '{\"enable_early_stop\":false}' simultaneously."
+                )
+            argument = self.enable_early_stop
+
+
 class LoadConfig:
     """
     Configuration for dynamic weight loading strategies
@@ -776,6 +844,7 @@ class FDConfig:
     load_config: LoadConfig = field(default=None, init=True)
     quant_config: Optional[QuantConfigBase] = None
     graph_opt_config: Optional[GraphOptimizationConfig] = None
+    early_stop_config: Optional[EarlyStopConfig] = None
     decoding_config: DecodingConfig = field(default=None, init=True)  # type: ignore
     cache_config: CacheConfig = field(default=None, init=True)  # type: ignore