Revert "make radix cache deterministic" (#11728)

python/sglang/srt/server_args.py

@@ -1411,6 +1411,13 @@ class ServerArgs:
                     f"Currently only {DETERMINISTIC_ATTENTION_BACKEND_CHOICES} attention backends are supported for deterministic inference."
                 )
 
+            # Currently, only FA3 supports radix cache. Support for other backends is in progress
+            if self.attention_backend != "fa3":
+                self.disable_radix_cache = True
+                logger.warning(
+                    f"Currently radix cache is not compatible with {self.attention_backend} attention backend for deterministic inference. It will be supported in the future."
+                )
+
             # Check TP size
             if self.tp_size > 1:
                 os.environ["NCCL_ALGO"] = "allreduce:tree"