fix: cache the loaded model

examples/main_cli_example.py

@@ -70,9 +70,7 @@ async def main(args):
     # )
 
     print(f"You: {query}")
-    chat_response = chat.ask(
+    chat_response = chat.ask(query, top_k=20, recompute_embeddings=True, complexity=32)
-        query, top_k=20, recompute_beighbor_embeddings=True, complexity=32
-    )
     print(f"Leann: {chat_response}")
 
 

packages/leann-backend-diskann/leann_backend_diskann/diskann_backend.py

@@ -4,7 +4,6 @@ import struct
 from pathlib import Path
 from typing import Dict, Any, List, Literal
 import contextlib
-import pickle
 
 from leann.searcher_base import BaseSearcher
 from leann.registry import register_backend
@@ -70,7 +69,6 @@ class DiskannBuilder(LeannBackendBuilderInterface):
         data_filename = f"{index_prefix}_data.bin"
         _write_vectors_to_bin(data, index_dir / data_filename)
 
-
         build_kwargs = {**self.build_params, **kwargs}
         metric_enum = _get_diskann_metrics().get(
             build_kwargs.get("distance_metric", "mips").lower()
@@ -207,8 +205,7 @@ class DiskannSearcher(BaseSearcher):
         )
 
         string_labels = [
-            [str(int_label) for int_label in batch_labels]
+            [str(int_label) for int_label in batch_labels] for batch_labels in labels
-            for batch_labels in labels
         ]
 
         return {"labels": string_labels, "distances": distances}

packages/leann-backend-hnsw/leann_backend_hnsw/hnsw_backend.py

@@ -1,10 +1,9 @@
 import numpy as np
 import os
 from pathlib import Path
-from typing import Dict, Any, List, Literal
+from typing import Dict, Any, List, Literal, Optional
-import pickle
 import shutil
-import time
+import logging
 
 from leann.searcher_base import BaseSearcher
 from .convert_to_csr import convert_hnsw_graph_to_csr
@@ -16,6 +15,8 @@ from leann.interface import (
     LeannBackendSearcherInterface,
 )
 
+logger = logging.getLogger(__name__)
+
 
 def get_metric_map():
     from . import faiss  # type: ignore
@@ -57,9 +58,9 @@ class HNSWBuilder(LeannBackendBuilderInterface):
         index_dir.mkdir(parents=True, exist_ok=True)
 
         if data.dtype != np.float32:
+            logger.warning(f"Converting data to float32, shape: {data.shape}")
             data = data.astype(np.float32)
 
-
         metric_enum = get_metric_map().get(self.distance_metric.lower())
         if metric_enum is None:
             raise ValueError(f"Unsupported distance_metric '{self.distance_metric}'.")
@@ -81,7 +82,7 @@ class HNSWBuilder(LeannBackendBuilderInterface):
     def _convert_to_csr(self, index_file: Path):
         """Convert built index to CSR format"""
         mode_str = "CSR-pruned" if self.is_recompute else "CSR-standard"
-        print(f"INFO: Converting HNSW index to {mode_str} format...")
+        logger.info(f"INFO: Converting HNSW index to {mode_str} format...")
 
         csr_temp_file = index_file.with_suffix(".csr.tmp")
 
@@ -90,11 +91,11 @@ class HNSWBuilder(LeannBackendBuilderInterface):
         )
 
         if success:
-            print("✅ CSR conversion successful.")
+            logger.info("✅ CSR conversion successful.")
             index_file_old = index_file.with_suffix(".old")
             shutil.move(str(index_file), str(index_file_old))
             shutil.move(str(csr_temp_file), str(index_file))
-            print(
+            logger.info(
                 f"INFO: Replaced original index with {mode_str} version at '{index_file}'"
             )
         else:
@@ -131,14 +132,12 @@ class HNSWSearcher(BaseSearcher):
 
         hnsw_config = faiss.HNSWIndexConfig()
         hnsw_config.is_compact = self.is_compact
-        hnsw_config.is_recompute = self.is_pruned or kwargs.get("is_recompute", False)
+        hnsw_config.is_recompute = (
-
+            self.is_pruned
-        if self.is_pruned and not hnsw_config.is_recompute:
+        )  # In C++ code, it's called is_recompute, but it's only for loading IIUC.
-            raise RuntimeError("Index is pruned but recompute is disabled.")
 
         self._index = faiss.read_index(str(index_file), faiss.IO_FLAG_MMAP, hnsw_config)
 
-
     def search(
         self,
         query: np.ndarray,
@@ -146,9 +145,9 @@ class HNSWSearcher(BaseSearcher):
         complexity: int = 64,
         beam_width: int = 1,
         prune_ratio: float = 0.0,
-        recompute_embeddings: bool = False,
+        recompute_embeddings: bool = True,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        zmq_port: int = 5557,
+        expected_zmq_port: Optional[int] = None,
         batch_size: int = 0,
         **kwargs,
     ) -> Dict[str, Any]:
@@ -166,7 +165,7 @@ class HNSWSearcher(BaseSearcher):
                 - "global": Use global PQ queue size for selection (default)
                 - "local": Local pruning, sort and select best candidates
                 - "proportional": Base selection on new neighbor count ratio
-            zmq_port: ZMQ port for embedding server
+            expected_zmq_port: ZMQ port for embedding server
             batch_size: Neighbor processing batch size, 0=disabled (HNSW-specific)
             **kwargs: Additional HNSW-specific parameters (for legacy compatibility)
 
@@ -175,15 +174,9 @@ class HNSWSearcher(BaseSearcher):
         """
         from . import faiss  # type: ignore
 
-        # Use recompute_embeddings parameter
+        if not recompute_embeddings:
-        use_recompute = recompute_embeddings or self.is_pruned
+            if self.is_pruned:
-        if use_recompute:
+                raise RuntimeError("Recompute is required for pruned index.")
-            meta_file_path = self.index_dir / f"{self.index_path.name}.meta.json"
-            if not meta_file_path.exists():
-                raise RuntimeError(
-                    f"FATAL: Recompute enabled but metadata file not found: {meta_file_path}"
-                )
-            self._ensure_server_running(str(meta_file_path), port=zmq_port, **kwargs)
 
         if query.dtype != np.float32:
             query = query.astype(np.float32)
@@ -191,7 +184,7 @@ class HNSWSearcher(BaseSearcher):
             faiss.normalize_L2(query)
 
         params = faiss.SearchParametersHNSW()
-        params.zmq_port = zmq_port
+        params.zmq_port = expected_zmq_port
         params.efSearch = complexity
         params.beam_size = beam_width
 
@@ -228,8 +221,7 @@ class HNSWSearcher(BaseSearcher):
         )
 
         string_labels = [
-            [str(int_label) for int_label in batch_labels]
+            [str(int_label) for int_label in batch_labels] for batch_labels in labels
-            for batch_labels in labels
         ]
 
         return {"labels": string_labels, "distances": distances}

packages/leann-backend-hnsw/leann_backend_hnsw/hnsw_embedding_server.py

@@ -29,7 +29,6 @@ logger = logging.getLogger(__name__)
 
 def create_hnsw_embedding_server(
     passages_file: Optional[str] = None,
-    passages_data: Optional[Dict[str, str]] = None,
     zmq_port: int = 5555,
     model_name: str = "sentence-transformers/all-mpnet-base-v2",
     distance_metric: str = "mips",
@@ -39,12 +38,6 @@ def create_hnsw_embedding_server(
     Create and start a ZMQ-based embedding server for HNSW backend.
     Simplified version using unified embedding computation module.
     """
-    # Auto-detect mode based on model name if not explicitly set
-    if embedding_mode == "sentence-transformers" and model_name.startswith(
-        "text-embedding-"
-    ):
-        embedding_mode = "openai"
-
     print(f"Starting HNSW server on port {zmq_port} with model {model_name}")
     print(f"Using embedding mode: {embedding_mode}")
 
@@ -64,6 +57,7 @@ def create_hnsw_embedding_server(
     finally:
         sys.path.pop(0)
 
+
     # Check port availability
     import socket
 
@@ -84,7 +78,9 @@ def create_hnsw_embedding_server(
         meta = json.load(f)
 
     passages = PassageManager(meta["passage_sources"])
-    print(f"Loaded PassageManager with {len(passages.global_offset_map)} passages from metadata")
+    print(
+        f"Loaded PassageManager with {len(passages.global_offset_map)} passages from metadata"
+    )
 
     def zmq_server_thread():
         """ZMQ server thread"""
@@ -112,7 +108,7 @@ def create_hnsw_embedding_server(
                             f"Processing direct text embedding request for {len(request_payload)} texts in {embedding_mode} mode"
                         )
 
-                        # Use unified embedding computation
+                        # Use unified embedding computation (now with model caching)
                         embeddings = compute_embeddings(
                             request_payload, model_name, mode=embedding_mode
                         )
@@ -148,15 +144,15 @@ def create_hnsw_embedding_server(
                             texts.append(txt)
                         except KeyError:
                             print(f"ERROR: Passage ID {nid} not found")
-                            raise RuntimeError(f"FATAL: Passage with ID {nid} not found")
+                            raise RuntimeError(
+                                f"FATAL: Passage with ID {nid} not found"
+                            )
                         except Exception as e:
                             print(f"ERROR: Exception looking up passage ID {nid}: {e}")
                             raise
 
                     # Process embeddings
-                    embeddings = compute_embeddings(
+                    embeddings = compute_embeddings(texts, model_name, mode=embedding_mode)
-                        texts, model_name, mode=embedding_mode
-                    )
                     print(
                         f"INFO: Computed embeddings for {len(texts)} texts, shape: {embeddings.shape}"
                     )
@@ -204,7 +200,9 @@ def create_hnsw_embedding_server(
                         passage_data = passages.get_passage(str(nid))
                         txt = passage_data["text"]
                         if not txt:
-                            raise RuntimeError(f"FATAL: Empty text for passage ID {nid}")
+                            raise RuntimeError(
+                                f"FATAL: Empty text for passage ID {nid}"
+                            )
                         texts.append(txt)
                     except KeyError:
                         raise RuntimeError(f"FATAL: Passage with ID {nid} not found")

packages/leann-core/src/leann/api.py

@@ -5,7 +5,9 @@ with the correct, original embedding logic from the user's reference code.
 
 import json
 import pickle
+from leann.interface import LeannBackendSearcherInterface
 import numpy as np
+import time
 from pathlib import Path
 from typing import List, Dict, Any, Optional, Literal
 from dataclasses import dataclass, field
@@ -126,6 +128,7 @@ class PassageManager:
     def get_passage(self, passage_id: str) -> Dict[str, Any]:
         if passage_id in self.global_offset_map:
             passage_file, offset = self.global_offset_map[passage_id]
+            # Lazy file opening - only open when needed
             with open(passage_file, "r", encoding="utf-8") as f:
                 f.seek(offset)
                 return json.loads(f.readline())
@@ -373,10 +376,12 @@ class LeannBuilder:
 
 class LeannSearcher:
     def __init__(self, index_path: str, enable_warmup: bool = False, **backend_kwargs):
-        meta_path_str = f"{index_path}.meta.json"
+        self.meta_path_str = f"{index_path}.meta.json"
-        if not Path(meta_path_str).exists():
+        if not Path(self.meta_path_str).exists():
-            raise FileNotFoundError(f"Leann metadata file not found at {meta_path_str}")
+            raise FileNotFoundError(
-        with open(meta_path_str, "r", encoding="utf-8") as f:
+                f"Leann metadata file not found at {self.meta_path_str}"
+            )
+        with open(self.meta_path_str, "r", encoding="utf-8") as f:
             self.meta_data = json.load(f)
         backend_name = self.meta_data["backend_name"]
         self.embedding_model = self.meta_data["embedding_model"]
@@ -390,7 +395,9 @@ class LeannSearcher:
             raise ValueError(f"Backend '{backend_name}' not found.")
         final_kwargs = {**self.meta_data.get("backend_kwargs", {}), **backend_kwargs}
         final_kwargs["enable_warmup"] = enable_warmup
-        self.backend_impl = backend_factory.searcher(index_path, **final_kwargs)
+        self.backend_impl: LeannBackendSearcherInterface = backend_factory.searcher(
+            index_path, **final_kwargs
+        )
 
     def search(
         self,
@@ -399,9 +406,9 @@ class LeannSearcher:
         complexity: int = 64,
         beam_width: int = 1,
         prune_ratio: float = 0.0,
-        recompute_embeddings: bool = False,
+        recompute_embeddings: bool = True,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        expected_zmq_port: Optional[int] = None,
+        expected_zmq_port: int = 5557,
         **kwargs,
     ) -> List[SearchResult]:
         print("🔍 DEBUG LeannSearcher.search() called:")
@@ -409,16 +416,21 @@ class LeannSearcher:
         print(f"  Top_k: {top_k}")
         print(f"  Additional kwargs: {kwargs}")
 
-        # Use backend's compute_query_embedding method
-        # This will automatically use embedding server if available and needed
-        import time
-
         start_time = time.time()
 
+        zmq_port = None
+        if recompute_embeddings:
+            zmq_port = self.backend_impl._ensure_server_running(
+                self.meta_path_str,
+                port=expected_zmq_port,
+                **kwargs,
+            )
+            del expected_zmq_port
+
         query_embedding = self.backend_impl.compute_query_embedding(
             query,
-            expected_zmq_port,
             use_server_if_available=recompute_embeddings,
+            zmq_port=zmq_port,
         )
         print(f"  Generated embedding shape: {query_embedding.shape}")
         embedding_time = time.time() - start_time
@@ -433,7 +445,7 @@ class LeannSearcher:
             prune_ratio=prune_ratio,
             recompute_embeddings=recompute_embeddings,
             pruning_strategy=pruning_strategy,
-            expected_zmq_port=expected_zmq_port,
+            expected_zmq_port=zmq_port,
             **kwargs,
         )
         search_time = time.time() - start_time
@@ -488,10 +500,10 @@ class LeannChat:
         complexity: int = 64,
         beam_width: int = 1,
         prune_ratio: float = 0.0,
-        recompute_embeddings: bool = False,
+        recompute_embeddings: bool = True,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        expected_zmq_port: Optional[int] = None,
         llm_kwargs: Optional[Dict[str, Any]] = None,
+        expected_zmq_port: int = 5557,
         **search_kwargs,
     ):
         if llm_kwargs is None:

packages/leann-core/src/leann/embedding_compute.py

@@ -6,11 +6,14 @@ Preserves all optimization parameters to ensure performance
 
 import numpy as np
 import torch
-from typing import List
+from typing import List, Dict, Any, Optional
 import logging
 
 logger = logging.getLogger(__name__)
 
+# Global model cache to avoid repeated loading
+_model_cache: Dict[str, Any] = {}
+
 
 def compute_embeddings(
     texts: List[str], model_name: str, mode: str = "sentence-transformers",is_build: bool = False
@@ -45,25 +48,12 @@ def compute_embeddings_sentence_transformers(
     is_build: bool = False,
 ) -> np.ndarray:
     """
-    Compute embeddings using SentenceTransformer
+    Compute embeddings using SentenceTransformer with model caching
-    Preserves all optimization parameters to ensure consistency with original embedding_server
-
-    Args:
-        texts: List of texts to compute embeddings for
-        model_name: SentenceTransformer model name
-        use_fp16: Whether to use FP16 precision
-        device: Device selection ('auto', 'cuda', 'mps', 'cpu')
-        batch_size: Batch size for processing
-
-    Returns:
-        Normalized embeddings array, shape: (len(texts), embedding_dim)
     """
     print(
         f"INFO: Computing embeddings for {len(texts)} texts using SentenceTransformer, model: '{model_name}'"
     )
 
-    from sentence_transformers import SentenceTransformer
-
     # Auto-detect device
     if device == "auto":
         if torch.cuda.is_available():
@@ -73,62 +63,72 @@ def compute_embeddings_sentence_transformers(
         else:
             device = "cpu"
 
-    print(f"INFO: Using device: {device}")
+    # Create cache key
+    cache_key = f"sentence_transformers_{model_name}_{device}_{use_fp16}"
     
-    # Prepare model and tokenizer optimization parameters (consistent with original embedding_server)
+    # Check if model is already cached
-    model_kwargs = {
+    if cache_key in _model_cache:
-        "torch_dtype": torch.float16 if use_fp16 else torch.float32,
+        print(f"INFO: Using cached model: {model_name}")
-        "low_cpu_mem_usage": True,
+        model = _model_cache[cache_key]
-        "_fast_init": True,  # Skip weight initialization checks for faster loading
+    else:
-    }
+        print(f"INFO: Loading and caching SentenceTransformer model: {model_name}")
+        from sentence_transformers import SentenceTransformer
 
-    tokenizer_kwargs = {
+        print(f"INFO: Using device: {device}")
-        "use_fast": True,  # Use fast tokenizer for better runtime performance
-    }
 
-    # Load SentenceTransformer (try local first, then network)
+        # Prepare model and tokenizer optimization parameters
-    print(f"INFO: Loading SentenceTransformer model: {model_name}")
+        model_kwargs = {
+            "torch_dtype": torch.float16 if use_fp16 else torch.float32,
+            "low_cpu_mem_usage": True,
+            "_fast_init": True,
+        }
 
-    try:
+        tokenizer_kwargs = {
-        # Try local loading (avoid network delays)
+            "use_fast": True,
-        model_kwargs["local_files_only"] = True
+        }
-        tokenizer_kwargs["local_files_only"] = True
 
-        model = SentenceTransformer(
-            model_name,
-            device=device,
-            model_kwargs=model_kwargs,
-            tokenizer_kwargs=tokenizer_kwargs,
-            local_files_only=True,
-        )
-        print("✅ Model loaded successfully! (local + optimized)")
-    except Exception as e:
-        print(f"Local loading failed ({e}), trying network download...")
-        # Fallback to network loading
-        model_kwargs["local_files_only"] = False
-        tokenizer_kwargs["local_files_only"] = False
-
-        model = SentenceTransformer(
-            model_name,
-            device=device,
-            model_kwargs=model_kwargs,
-            tokenizer_kwargs=tokenizer_kwargs,
-            local_files_only=False,
-        )
-        print("✅ Model loaded successfully! (network + optimized)")
-
-    # Apply additional optimizations (if supported)
-    if use_fp16 and device in ["cuda", "mps"]:
         try:
-            model = model.half()
+            # Try local loading first
-            model = torch.compile(model)
+            model_kwargs["local_files_only"] = True
-            print(f"✅ Using FP16 precision and compile optimization: {model_name}")
+            tokenizer_kwargs["local_files_only"] = True
-        except Exception as e:
-            print(
-                f"FP16 or compile optimization failed, continuing with default settings: {e}"
-            )
 
-    # Compute embeddings (using SentenceTransformer's optimized implementation)
+            model = SentenceTransformer(
+                model_name,
+                device=device,
+                model_kwargs=model_kwargs,
+                tokenizer_kwargs=tokenizer_kwargs,
+                local_files_only=True,
+            )
+            print("✅ Model loaded successfully! (local + optimized)")
+        except Exception as e:
+            print(f"Local loading failed ({e}), trying network download...")
+            # Fallback to network loading
+            model_kwargs["local_files_only"] = False
+            tokenizer_kwargs["local_files_only"] = False
+
+            model = SentenceTransformer(
+                model_name,
+                device=device,
+                model_kwargs=model_kwargs,
+                tokenizer_kwargs=tokenizer_kwargs,
+                local_files_only=False,
+            )
+            print("✅ Model loaded successfully! (network + optimized)")
+
+        # Apply additional optimizations (if supported)
+        if use_fp16 and device in ["cuda", "mps"]:
+            try:
+                model = model.half()
+                model = torch.compile(model)
+                print(f"✅ Using FP16 precision and compile optimization: {model_name}")
+            except Exception as e:
+                print(f"FP16 or compile optimization failed: {e}")
+
+        # Cache the model
+        _model_cache[cache_key] = model
+        print(f"✅ Model cached: {cache_key}")
+
+    # Compute embeddings
     print("INFO: Starting embedding computation...")
 
     embeddings = model.encode(
@@ -136,7 +136,7 @@ def compute_embeddings_sentence_transformers(
         batch_size=batch_size,
         show_progress_bar=is_build,  # Don't show progress bar in server environment
         convert_to_numpy=True,
-        normalize_embeddings=False,  # Keep consistent with original API behavior
+        normalize_embeddings=False,
         device=device,
     )
 
@@ -166,7 +166,14 @@ def compute_embeddings_openai(texts: List[str], model_name: str) -> np.ndarray:
     if not api_key:
         raise RuntimeError("OPENAI_API_KEY environment variable not set")
 
-    client = openai.OpenAI(api_key=api_key)
+    # Cache OpenAI client
+    cache_key = "openai_client"
+    if cache_key in _model_cache:
+        client = _model_cache[cache_key]
+    else:
+        client = openai.OpenAI(api_key=api_key)
+        _model_cache[cache_key] = client
+        print("✅ OpenAI client cached")
 
     print(
         f"INFO: Computing embeddings for {len(texts)} texts using OpenAI API, model: '{model_name}'"
@@ -214,7 +221,6 @@ def compute_embeddings_mlx(
     try:
         import mlx.core as mx
         from mlx_lm.utils import load
-        from tqdm import tqdm
     except ImportError as e:
         raise RuntimeError(
             "MLX or related libraries not available. Install with: uv pip install mlx mlx-lm"
@@ -224,8 +230,16 @@ def compute_embeddings_mlx(
         f"INFO: Computing embeddings for {len(chunks)} chunks using MLX model '{model_name}' with batch_size={batch_size}..."
     )
 
-    # Load model and tokenizer
+    # Cache MLX model and tokenizer
-    model, tokenizer = load(model_name)
+    cache_key = f"mlx_{model_name}"
+    if cache_key in _model_cache:
+        print(f"INFO: Using cached MLX model: {model_name}")
+        model, tokenizer = _model_cache[cache_key]
+    else:
+        print(f"INFO: Loading and caching MLX model: {model_name}")
+        model, tokenizer = load(model_name)
+        _model_cache[cache_key] = (model, tokenizer)
+        print(f"✅ MLX model cached: {cache_key}")
 
     # Process chunks in batches with progress bar
     all_embeddings = []

packages/leann-core/src/leann/interface.py

@@ -34,6 +34,13 @@ class LeannBackendSearcherInterface(ABC):
         """
         pass
 
+    @abstractmethod
+    def _ensure_server_running(
+        self, passages_source_file: str, port: Optional[int], **kwargs
+    ) -> int:
+        """Ensure server is running"""
+        pass
+
     @abstractmethod
     def search(
         self,
@@ -44,7 +51,7 @@ class LeannBackendSearcherInterface(ABC):
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = False,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        expected_zmq_port: Optional[int] = None,
+        zmq_port: Optional[int] = None,
         **kwargs,
     ) -> Dict[str, Any]:
         """Search for nearest neighbors
@@ -57,7 +64,7 @@ class LeannBackendSearcherInterface(ABC):
             prune_ratio: Ratio of neighbors to prune via approximate distance (0.0-1.0)
             recompute_embeddings: Whether to fetch fresh embeddings from server vs use stored PQ codes
             pruning_strategy: PQ candidate selection strategy - "global" (default), "local", or "proportional"
-            expected_zmq_port: ZMQ port for embedding server communication
+            zmq_port: ZMQ port for embedding server communication
             **kwargs: Backend-specific parameters
 
         Returns:
@@ -69,14 +76,14 @@ class LeannBackendSearcherInterface(ABC):
     def compute_query_embedding(
         self,
         query: str,
-        expected_zmq_port: Optional[int] = None,
         use_server_if_available: bool = True,
+        zmq_port: Optional[int] = None,
     ) -> np.ndarray:
         """Compute embedding for a query string
 
         Args:
             query: The query string to embed
-            expected_zmq_port: ZMQ port for embedding server
+            zmq_port: ZMQ port for embedding server
             use_server_if_available: Whether to try using embedding server first
 
         Returns:

packages/leann-core/src/leann/searcher_base.py

@@ -1,5 +1,4 @@
 import json
-import pickle
 from abc import ABC, abstractmethod
 from pathlib import Path
 from typing import Dict, Any, Literal, Optional
@@ -88,15 +87,15 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
     def compute_query_embedding(
         self,
         query: str,
-        expected_zmq_port: int = 5557,
         use_server_if_available: bool = True,
+        zmq_port: int = 5557,
     ) -> np.ndarray:
         """
         Compute embedding for a query string.
 
         Args:
             query: The query string to embed
-            expected_zmq_port: ZMQ port for embedding server
+            zmq_port: ZMQ port for embedding server
             use_server_if_available: Whether to try using embedding server first
 
         Returns:
@@ -110,7 +109,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
                     self.index_dir / f"{self.index_path.name}.meta.json"
                 )
                 zmq_port = self._ensure_server_running(
-                    str(passages_source_file), expected_zmq_port
+                    str(passages_source_file), zmq_port
                 )
 
                 return self._compute_embedding_via_server([query], zmq_port)[
@@ -168,7 +167,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
         prune_ratio: float = 0.0,
         recompute_embeddings: bool = False,
         pruning_strategy: Literal["global", "local", "proportional"] = "global",
-        expected_zmq_port: Optional[int] = None,
+        zmq_port: Optional[int] = None,
         **kwargs,
     ) -> Dict[str, Any]:
         """
@@ -182,7 +181,7 @@ class BaseSearcher(LeannBackendSearcherInterface, ABC):
             prune_ratio: Ratio of neighbors to prune via approximate distance (0.0-1.0)
             recompute_embeddings: Whether to fetch fresh embeddings from server vs use stored PQ codes
             pruning_strategy: PQ candidate selection strategy - "global" (default), "local", or "proportional"
-            expected_zmq_port: ZMQ port for embedding server communication
+            zmq_port: ZMQ port for embedding server communication
             **kwargs: Backend-specific parameters (e.g., batch_size, dedup_node_dis, etc.)
 
         Returns: