feat(server): Provide ability to dynamically allocate all threads if desired using -1 (#1364)

Author: sean-bailey

llama_cpp/server/settings.py

@@ -3,7 +3,7 @@
 import multiprocessing
 
 from typing import Optional, List, Literal, Union
-from pydantic import Field
+from pydantic import Field, root_validator
 from pydantic_settings import BaseSettings
 
 import llama_cpp
@@ -67,12 +67,12 @@ class ModelSettings(BaseSettings):
     n_threads: int = Field(
         default=max(multiprocessing.cpu_count() // 2, 1),
         ge=1,
-        description="The number of threads to use.",
+        description="The number of threads to use. Use -1 for max cpu threads",
     )
     n_threads_batch: int = Field(
         default=max(multiprocessing.cpu_count(), 1),
         ge=0,
-        description="The number of threads to use when batch processing.",
+        description="The number of threads to use when batch processing. Use -1 for max cpu threads",
     )
     rope_scaling_type: int = Field(
         default=llama_cpp.LLAMA_ROPE_SCALING_TYPE_UNSPECIFIED
@@ -173,6 +173,16 @@ class ModelSettings(BaseSettings):
         default=True, description="Whether to print debug information."
     )
 
+    @root_validator(pre=True)  # pre=True to ensure this runs before any other validation
+    def set_dynamic_defaults(cls, values):
+        # If n_threads or n_threads_batch is -1, set it to multiprocessing.cpu_count()
+        cpu_count = multiprocessing.cpu_count()
+        if values.get('n_threads', 0) == -1:
+            values['n_threads'] = cpu_count
+        if values.get('n_threads_batch', 0) == -1:
+            values['n_threads_batch'] = cpu_count
+        return values
+
 
 class ServerSettings(BaseSettings):
     """Server settings used to configure the FastAPI and Uvicorn server."""