添加并发请求限制，避免崩溃

app/api/qgis_map_export.py

@@ -20,7 +20,6 @@ from app.config.paths import get_logger
 from app.config.qgis_mappings import build_static_layers_config, get_gpkg_dir
 from app.repositories import qgis_repository
 from app.schemas.api_schemas import QgisMapExportResponse, QgisMapExportRequest
-from app.utils.api_deps import get_prediction_semaphore
 from app.utils.db_helper import db_helper
 from config import settings
 
@@ -179,18 +178,22 @@ def _build_qgis_config(batch_folder: str) -> dict:
 # 接口实现
 # ============================================================
 
+# 全局并发限制
+import asyncio as _asyncio
+_concurrent = getattr(settings, "QGIS_MAX_CONCURRENT", 2)
+_qgis_semaphore = _asyncio.Semaphore(_concurrent)
+
+
 @router.post("/export/map", response_model=QgisMapExportResponse, summary="QGIS 批量专题图导出")
 async def export_map(req: QgisMapExportRequest):
     """
-    根据模拟ID批量导出专题图。同一 occurred_time 视为同一场灾害，共享文件夹
+    根据模拟ID批量导出专题图。同一 inferenceId 共享文件夹，增量产出缺失图片。
     """
     from app.services.qgis.qgis_env import is_qgis_available
     if not is_qgis_available():
-        raise HTTPException(status_code=503, detail="QGIS 环境不可用（未找到 QGIS Python 3.12 解释器）")
+        raise HTTPException(status_code=503, detail="QGIS 环境不可用")
 
-    semaphore = get_prediction_semaphore()
-
-    async with semaphore:
+    async with _qgis_semaphore:
         inference_id = req.inferenceId
         loop = asyncio.get_event_loop()