diff --git a/backend/app/routers/websites.py b/backend/app/routers/websites.py
index 12892fd..43883f4 100644
--- a/backend/app/routers/websites.py
+++ b/backend/app/routers/websites.py
@@ -2,10 +2,15 @@ from __future__ import annotations
 
 import json
 import logging
+import secrets
+import queue as _queue
+import threading as _threading
+import time
 from datetime import datetime, timezone
-from typing import List
+from typing import Any, List
 
 from fastapi import APIRouter, Depends, HTTPException, Query, status
+from fastapi.responses import StreamingResponse
 from sqlalchemy.orm import Session
 
 from app.database import get_db
@@ -75,6 +80,132 @@ SENSITIVE_CREDENTIAL_KEYS = {
 }
 ALGORITHMS = {"max_plus_percent", "average_plus_percent", "min_plus_percent", "priority_weighted_plus_percent"}
 
+# ——— 服务端任务锁（防止同一网站同类任务并发执行） ———
+_running_tasks: dict[str, dict[str, Any]] = {}
+_tasks_lock = _threading.Lock()
+
+
+def _try_start_task(wid: int, task_type: str, timeout_minutes: int = 240) -> tuple[bool, str | None]:
+    """尝试获取任务锁，成功返回 (True, token)，失败返回 (False, None)。
+
+    token 用于 _finish_task 校验锁所有权：只有当前锁记录的 token 与传入 token
+    一致时才释放锁。防止旧 worker（强制过期后仍存活的线程）误删新任务的锁。
+    """
+    key = f"task:{task_type}:{wid}"
+    now = time.monotonic()
+    token = secrets.token_hex(16)
+    with _tasks_lock:
+        entry = _running_tasks.get(key)
+        if entry and (now - entry["started_at"]) < timeout_minutes * 60:
+            return False, None
+        if entry:
+            logger.warning("task lock force-expired wid=%s task_type=%s elapsed=%.1fmin", wid, task_type, (now - entry["started_at"]) / 60)
+        _running_tasks[key] = {"started_at": now, "token": token}
+        return True, token
+
+
+def _finish_task(wid: int, task_type: str, token: str | None):
+    """释放任务锁，但仅当 token 与当前锁所有者一致时执行。
+
+    如果锁已被其他任务强制过期并替换，token 不匹配，则仅记 warning，
+    不删除新任务的锁。
+    """
+    key = f"task:{task_type}:{wid}"
+    with _tasks_lock:
+        entry = _running_tasks.get(key)
+        if entry is None:
+            return
+        if entry.get("token") != token:
+            logger.warning("task lock not released: token mismatch (stale worker) wid=%s task_type=%s", wid, task_type)
+            return
+        _running_tasks.pop(key, None)
+
+
+# ——— 心跳包装器：在同步生成器执行期间确保定期有事件输出 ———
+def _with_background_heartbeat(gen_fn, interval: float = 10, timeout_factor: int = 3, *, task_wid: int | None = None, task_type: str | None = None, task_token: str | None = None, **gen_kwargs):
+    """在后台线程运行 gen_fn(**gen_kwargs)，主线程通过队列消费事件。
+
+    独立心跳线程每 *interval* 秒检查一次，若主线程消费落后（队列为空）则输出
+    heartbeat 事件。防止在单个远端请求阻塞期间无事件产生。
+
+    任务锁生命周期（解决客户端断开后锁提前释放的问题）：
+    - 任务锁的获取（_try_start_task）在路由处理函数中完成。
+    - 任务锁的释放（_finish_task）在 _run() 的 finally 中，由业务线程
+      自身执行。因此锁的释放与业务线程的结束严格绑定。
+    - 客户端断开只触发 cancel 信号和队列停止，不会调用 _finish_task。
+    - 即使业务线程阻塞在远端 HTTP 请求中，锁仍然保持持有状态，
+      直到请求返回（超时或完成）且线程退出。
+    - 取消信号拦截在下一次 Python 代码执行边界（队列写/循环头），
+      无法中断阻塞中的系统调用，但锁不会提前释放。
+
+    队列满保护：
+    - q.put(timeout=5) + 循环重试，避免队列满后后台线程永久阻塞。
+      重试时检查 cancel，允许线程在被阻塞时响应取消。
+    """
+    q = _queue.Queue(maxsize=100)
+    stop = _threading.Event()
+    cancel = _threading.Event()
+
+    def _run():
+        try:
+            for event, data in gen_fn(**gen_kwargs):
+                if cancel.is_set():
+                    return
+                # 使用超时 put 防止队列满后永久阻塞
+                while True:
+                    try:
+                        q.put((event, data), timeout=5)
+                        break
+                    except _queue.Full:
+                        if cancel.is_set():
+                            return
+        except Exception as exc:
+            try:
+                q.put(("error", {"message": str(exc)}), timeout=2)
+            except _queue.Full:
+                pass
+        finally:
+            stop.set()
+            # 业务线程结束后才释放任务锁，并通过 token 校验所有权，
+            # 防止过期后仍存活的旧 worker 误删新任务锁。
+            if task_wid is not None and task_type is not None:
+                _finish_task(task_wid, task_type, task_token)
+
+    def _heartbeat():
+        while not stop.wait(timeout=interval):
+            if cancel.is_set():
+                return
+            try:
+                q.put(("heartbeat", {}), timeout=2)
+            except _queue.Full:
+                pass
+
+    t_work = _threading.Thread(target=_run, daemon=True)
+    t_hb = _threading.Thread(target=_heartbeat, daemon=True)
+    t_work.start()
+    t_hb.start()
+
+    try:
+        while True:
+            try:
+                event, data = q.get(timeout=interval * timeout_factor)
+                yield event, data
+                if event in ("complete", "error"):
+                    break
+            except _queue.Empty:
+                cancel.set()
+                yield "error", {"message": "内部处理线程长时间无响应，任务异常中断"}
+                break
+    except GeneratorExit:
+        # 客户端断开连接或消费方异常退出 → 通知后台线程停止
+        cancel.set()
+        raise
+    finally:
+        cancel.set()
+        stop.set()
+        # 注意：不在此处释放任务锁。_finish_task 由 _run() 的 finally 负责，
+        # 确保锁释放与业务线程终止严格同步。
+
 
 def _mask(cfg: dict) -> dict:
     masked = {}
@@ -1480,6 +1611,7 @@ def _sync_upstream_models_generator(wid: int, db: Session):
             return
 
         yield "start", {"total_accounts": len(candidates)}
+        last_event_at = time.monotonic()
 
         upstream_ids = {cand["upstream_id"] for cand in candidates.values()}
         upstreams_map = {up.id: up for up in db.query(Upstream).filter(Upstream.id.in_(upstream_ids)).all()}
@@ -1500,6 +1632,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
                 continue
 
             acc_name = remote_acc.get("name")
@@ -1518,9 +1653,13 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
                 continue
 
             upstream = upstreams_map.get(cand["upstream_id"])
+
             upstream_base_url = upstream.base_url if upstream else None
 
             if not upstream_base_url or not upstream_base_url.strip():
@@ -1534,6 +1673,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
                 continue
 
             # 1. 先安全修复 base_url (不依赖同步模型结果)
@@ -1563,6 +1705,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                     )
                     items.append(item)
                     yield "item", item.model_dump()
+                    if time.monotonic() - last_event_at >= 10:
+                        yield "heartbeat", {}
+                        last_event_at = time.monotonic()
                     continue
                 current_creds["api_key"] = local_key_value
 
@@ -1579,6 +1724,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
                 continue
 
             # 2. 调用 sub2api 同步模型
@@ -1598,6 +1746,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                     )
                     items.append(item)
                     yield "item", item.model_dump()
+                    if time.monotonic() - last_event_at >= 10:
+                        yield "heartbeat", {}
+                        last_event_at = time.monotonic()
                     continue
 
                 # 3. 模型同步成功后，在 current_creds 基础上替换 model_mapping 并写回
@@ -1615,6 +1766,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
             except Exception as e:
                 item = SyncUpstreamModelsItem(
                     account_id=aid,
@@ -1626,6 +1780,9 @@ def _sync_upstream_models_generator(wid: int, db: Session):
                 )
                 items.append(item)
                 yield "item", item.model_dump()
+                if time.monotonic() - last_event_at >= 10:
+                    yield "heartbeat", {}
+                    last_event_at = time.monotonic()
 
         success_count = sum(1 for item in items if item.status == "success")
         failed_count = sum(1 for item in items if item.status == "failed")
@@ -1655,32 +1812,45 @@ def sync_website_accounts_upstream_models(
     _=Depends(get_current_user),
 ):
     """一键同步上游模型"""
+    ok, _sync_token = _try_start_task(wid, "sync_models")
+    if not ok:
+        raise HTTPException(409, "该网站的同步上游模型正在执行中")
+
+    logger.info("sync_models start wid=%s", wid)
+    t0 = time.monotonic()
     items = []
     success = False
     message = ""
     error_occurred = False
 
-    for event, data in _sync_upstream_models_generator(wid, db):
-        if event == "item":
-            items.append(SyncUpstreamModelsItem(**data))
-        elif event == "complete":
-            success = data["success"]
-            message = data["message"]
-        elif event == "error":
-            error_occurred = True
-            message = data["message"]
+    try:
+        for event, data in _sync_upstream_models_generator(wid, db):
+            if event == "item":
+                items.append(SyncUpstreamModelsItem(**data))
+            elif event == "complete":
+                success = data["success"]
+                message = data["message"]
+            elif event == "error":
+                error_occurred = True
+                message = data["message"]
+    finally:
+        _finish_task(wid, "sync_models", _sync_token)
 
     if error_occurred:
         if message == "website not found":
             raise HTTPException(404, "website not found")
         if "only sub2api" in message:
             raise HTTPException(400, message)
+        elapsed = time.monotonic() - t0
+        logger.info("sync_models complete wid=%s error=%s elapsed=%.1fs", wid, message, elapsed)
         return SyncUpstreamModelsResponse(
             success=False,
             message=message,
             items=[]
         )
 
+    elapsed = time.monotonic() - t0
+    logger.info("sync_models complete wid=%s items=%d success=%s elapsed=%.1fs", wid, len(items), success, elapsed)
     return SyncUpstreamModelsResponse(
         success=success,
         message=message,
@@ -1695,27 +1865,43 @@ def sync_website_accounts_upstream_models_stream(
     _=Depends(get_current_user),
 ):
     """流式一键同步上游模型"""
-    from fastapi.responses import StreamingResponse
 
     def event_generator():
-        for event, data in _sync_upstream_models_generator(wid, db):
+        ok, _sync_token = _try_start_task(wid, "sync_models")
+        if not ok:
+            yield json.dumps({"event": "error", "data": {"message": "该网站的同步上游模型正在执行中"}}, ensure_ascii=False) + "\n"
+            return
+
+        logger.info("sync_models/stream start wid=%s", wid)
+        t0 = time.monotonic()
+        for event, data in _with_background_heartbeat(
+            _sync_upstream_models_generator, wid=wid, db=db,
+            task_wid=wid, task_type="sync_models", task_token=_sync_token,
+        ):
             yield json.dumps({"event": event, "data": data}, ensure_ascii=False) + "\n"
 
-    return StreamingResponse(event_generator(), media_type="application/x-ndjson")
+        elapsed = time.monotonic() - t0
+        logger.info("sync_models/stream complete wid=%s elapsed=%.1fs", wid, elapsed)
+
+    return StreamingResponse(
+        event_generator(),
+        media_type="application/x-ndjson",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+        },
+    )
 
 
-@router.post("/api/websites/{wid}/groups/organize", response_model=OrganizeGroupsResponse)
-def organize_website_groups(
-    wid: int,
-    db: Session = Depends(get_db),
-    _=Depends(get_current_user),
-):
-    """一键整理分组：按现有绑定关系导入/自愈账号"""
+def _organize_website_groups_generator(wid: int, db: Session):
+    """一键整理分组生成器，逐条产生事件供流式或批量消费。"""
     website = db.query(Website).filter(Website.id == wid).first()
     if not website:
-        raise HTTPException(404, "website not found")
+        yield "error", {"message": "website not found"}
+        return
     if website.site_type != "sub2api":
-        raise HTTPException(400, "目前只支持 sub2api")
+        yield "error", {"message": "目前只支持 sub2api"}
+        return
 
     # 1. 读取当前网站的所有启用绑定关系
     bindings = (
@@ -1742,6 +1928,23 @@ def organize_website_groups(
 
     items: list[OrganizeGroupsItem] = []
 
+    # 预计算总处理项数（用于流式进度）；missing_key 也算 1 项
+    total_items = 0
+    for b in bindings:
+        for src in binding_sources(b):
+            uid = src.get("upstream_id")
+            gid = src.get("group_id")
+            if uid and gid:
+                cnt = db.query(UpstreamGeneratedKey).filter(
+                    UpstreamGeneratedKey.upstream_id == uid,
+                    UpstreamGeneratedKey.group_id == gid,
+                    UpstreamGeneratedKey.status != "orphaned",
+                ).count()
+                total_items += max(1, cnt)
+
+    yield "start", {"total_items": total_items, "total_bindings": len(bindings)}
+    last_event_at = time.monotonic()
+
     # 2. 收集所有的 upstream_id 并执行对账，以保证本地 Key 的状态最新
     upstream_ids = set()
     for b in bindings:
@@ -1854,20 +2057,23 @@ def organize_website_groups(
                 )
 
                 if not keys:
-                    items.append(
-                        OrganizeGroupsItem(
-                            target_group_id=str(target_group_id),
-                            target_group_name=target_group_name,
-                            upstream_name=upstream_name,
-                            source_group_id=str(gid),
-                            source_group_name=str(source_group_name),
-                            key_name="",
-                            account_id=None,
-                            account_name=None,
-                            status="missing_key",
-                            message="请先生成上游 Key",
-                        )
+                    _item = OrganizeGroupsItem(
+                        target_group_id=str(target_group_id),
+                        target_group_name=target_group_name,
+                        upstream_name=upstream_name,
+                        source_group_id=str(gid),
+                        source_group_name=str(source_group_name),
+                        key_name="",
+                        account_id=None,
+                        account_name=None,
+                        status="missing_key",
+                        message="请先生成上游 Key",
                     )
+                    items.append(_item)
+                    yield "item", _item.model_dump()
+                    if time.monotonic() - last_event_at >= 10:
+                        yield "heartbeat", {}
+                        last_event_at = time.monotonic()
                     continue
 
                 # 获取来源上游的 Base URL 用于账号创建
@@ -1876,20 +2082,23 @@ def organize_website_groups(
                 for row in keys:
                     # 跳过状态为 failed 的 Key
                     if row.status == "failed":
-                        items.append(
-                            OrganizeGroupsItem(
-                                target_group_id=str(target_group_id),
-                                target_group_name=target_group_name,
-                                upstream_name=upstream_name,
-                                source_group_id=str(gid),
-                                source_group_name=str(source_group_name),
-                                key_name=row.key_name,
-                                account_id=None,
-                                account_name=None,
-                                status="failed",
-                                message="上游 Key 生成状态为失败",
-                            )
+                        _item = OrganizeGroupsItem(
+                            target_group_id=str(target_group_id),
+                            target_group_name=target_group_name,
+                            upstream_name=upstream_name,
+                            source_group_id=str(gid),
+                            source_group_name=str(source_group_name),
+                            key_name=row.key_name,
+                            account_id=None,
+                            account_name=None,
+                            status="failed",
+                            message="上游 Key 生成状态为失败",
                         )
+                        items.append(_item)
+                        yield "item", _item.model_dump()
+                        if time.monotonic() - last_event_at >= 10:
+                            yield "heartbeat", {}
+                            last_event_at = time.monotonic()
                         continue
 
                     # 检测平台类型
@@ -1906,19 +2115,22 @@ def organize_website_groups(
 
                         if remote_account_ids is None:
                             # 账号列表获取失败，无法校验状态，保守跳过
-                            items.append(
-                                OrganizeGroupsItem(
-                                    target_group_id=str(target_group_id),
-                                    target_group_name=target_group_name,
-                                    upstream_name=upstream_name,
-                                    source_group_id=str(gid),
-                                    source_group_name=str(source_group_name),
-                                    key_name=row.key_name,
-                                    account_id=old_account_id,
-                                    status="failed",
-                                    message="无法校验目标账号状态，已保守跳过",
-                                )
+                            _item = OrganizeGroupsItem(
+                                target_group_id=str(target_group_id),
+                                target_group_name=target_group_name,
+                                upstream_name=upstream_name,
+                                source_group_id=str(gid),
+                                source_group_name=str(source_group_name),
+                                key_name=row.key_name,
+                                account_id=old_account_id,
+                                status="failed",
+                                message="无法校验目标账号状态，已保守跳过",
                             )
+                            items.append(_item)
+                            yield "item", _item.model_dump()
+                            if time.monotonic() - last_event_at >= 10:
+                                yield "heartbeat", {}
+                                last_event_at = time.monotonic()
                             continue
 
                         remote_acc = remote_account_map.get(str(old_account_id))
@@ -1989,35 +2201,40 @@ def organize_website_groups(
                                     row.imported_target_group_name = target_group_names.get(str(target_group_id))
                                     db.commit()
 
-                                items.append(
-                                    OrganizeGroupsItem(
-                                        target_group_id=str(target_group_id),
-                                        target_group_name=target_group_name,
-                                        upstream_name=upstream_name,
-                                        source_group_id=str(gid),
-                                        source_group_name=str(source_group_name),
-                                        key_name=row.key_name,
-                                        account_id=old_account_id,
-                                        account_name=str(remote_acc.get("name") or ""),
-                                        status="exists",
-                                        message=msg,
-                                    )
-                                )
+                                items.append(_item := OrganizeGroupsItem(
+                                    target_group_id=str(target_group_id),
+                                    target_group_name=target_group_name,
+                                    upstream_name=upstream_name,
+                                    source_group_id=str(gid),
+                                    source_group_name=str(source_group_name),
+                                    key_name=row.key_name,
+                                    account_id=old_account_id,
+                                    account_name=str(remote_acc.get("name") or ""),
+                                    status="exists",
+                                    message=msg,
+                                ))
+                                yield "item", _item.model_dump()
+                                if time.monotonic() - last_event_at >= 10:
+                                    yield "heartbeat", {}
+                                    last_event_at = time.monotonic()
                                 continue
                             except Exception as exc:
-                                items.append(
-                                    OrganizeGroupsItem(
-                                        target_group_id=str(target_group_id),
-                                        target_group_name=target_group_name,
-                                        upstream_name=upstream_name,
-                                        source_group_id=str(gid),
-                                        source_group_name=str(source_group_name),
-                                        key_name=row.key_name,
-                                        account_id=old_account_id,
-                                        status="failed",
-                                        message=f"更新绑定失败: {exc}",
-                                    )
+                                _item = OrganizeGroupsItem(
+                                    target_group_id=str(target_group_id),
+                                    target_group_name=target_group_name,
+                                    upstream_name=upstream_name,
+                                    source_group_id=str(gid),
+                                    source_group_name=str(source_group_name),
+                                    key_name=row.key_name,
+                                    account_id=old_account_id,
+                                    status="failed",
+                                    message=f"更新绑定失败: {exc}",
                                 )
+                                items.append(_item)
+                                yield "item", _item.model_dump()
+                                if time.monotonic() - last_event_at >= 10:
+                                    yield "heartbeat", {}
+                                    last_event_at = time.monotonic()
                                 continue
                         else:
                             # 远端已删除，清理标记后进行重建
@@ -2032,18 +2249,21 @@ def organize_website_groups(
 
                     # 2. 检查是否有明文 Key
                     if not row.key_value:
-                        items.append(
-                            OrganizeGroupsItem(
-                                target_group_id=str(target_group_id),
-                                target_group_name=target_group_name,
-                                upstream_name=upstream_name,
-                                source_group_id=str(gid),
-                                source_group_name=str(source_group_name),
-                                key_name=row.key_name,
-                                status="failed",
-                                message="该 Key 无明文值，无法导入",
-                            )
+                        _item = OrganizeGroupsItem(
+                            target_group_id=str(target_group_id),
+                            target_group_name=target_group_name,
+                            upstream_name=upstream_name,
+                            source_group_id=str(gid),
+                            source_group_name=str(source_group_name),
+                            key_name=row.key_name,
+                            status="failed",
+                            message="该 Key 无明文值，无法导入",
                         )
+                        items.append(_item)
+                        yield "item", _item.model_dump()
+                        if time.monotonic() - last_event_at >= 10:
+                            yield "heartbeat", {}
+                            last_event_at = time.monotonic()
                         continue
 
                     # 3. 创建账号并绑定当前目标分组
@@ -2091,37 +2311,43 @@ def organize_website_groups(
                         if account_id:
                             remote_account_map[str(account_id)] = created
 
-                        items.append(
-                            OrganizeGroupsItem(
-                                target_group_id=str(target_group_id),
-                                target_group_name=target_group_name,
-                                upstream_name=upstream_name,
-                                source_group_id=str(gid),
-                                source_group_name=str(source_group_name),
-                                key_name=row.key_name,
-                                account_id=account_id or None,
-                                account_name=str(created.get("name") or account_name),
-                                status="recreated" if is_recreated else "created",
-                                message="清理后重建账号" if is_recreated else "已创建账号",
-                            )
+                        _item = OrganizeGroupsItem(
+                            target_group_id=str(target_group_id),
+                            target_group_name=target_group_name,
+                            upstream_name=upstream_name,
+                            source_group_id=str(gid),
+                            source_group_name=str(source_group_name),
+                            key_name=row.key_name,
+                            account_id=account_id or None,
+                            account_name=str(created.get("name") or account_name),
+                            status="recreated" if is_recreated else "created",
+                            message="清理后重建账号" if is_recreated else "已创建账号",
                         )
+                        items.append(_item)
+                        yield "item", _item.model_dump()
+                        if time.monotonic() - last_event_at >= 10:
+                            yield "heartbeat", {}
+                            last_event_at = time.monotonic()
                     except Exception as exc:
                         logger.exception("organize create account failed website=%s key=%s", wid, row.id)
                         row.status = "import_failed"
                         row.error = str(exc)
                         db.commit()
-                        items.append(
-                            OrganizeGroupsItem(
-                                target_group_id=str(target_group_id),
-                                target_group_name=target_group_name,
-                                upstream_name=upstream_name,
-                                source_group_id=str(gid),
-                                source_group_name=str(source_group_name),
-                                key_name=row.key_name,
-                                status="failed",
-                                message=str(exc),
-                            )
+                        _item = OrganizeGroupsItem(
+                            target_group_id=str(target_group_id),
+                            target_group_name=target_group_name,
+                            upstream_name=upstream_name,
+                            source_group_id=str(gid),
+                            source_group_name=str(source_group_name),
+                            key_name=row.key_name,
+                            status="failed",
+                            message=str(exc),
                         )
+                        items.append(_item)
+                        yield "item", _item.model_dump()
+                        if time.monotonic() - last_event_at >= 10:
+                            yield "heartbeat", {}
+                            last_event_at = time.monotonic()
 
     created_count = sum(1 for item in items if item.status == "created")
     recreated_count = sum(1 for item in items if item.status == "recreated")
@@ -2151,10 +2377,82 @@ def organize_website_groups(
         logger.warning("failed to sync priorities after organize for website %s: %s", wid, exc)
 
     message = "整理完成：" + " / ".join(parts) if parts else "整理完成：无任何绑定或数据"
-    return OrganizeGroupsResponse(
-        success=failed_count == 0,
-        message=message,
-        items=items,
+    yield "complete", {
+        "success": failed_count == 0,
+        "message": message,
+        "items": [item.model_dump() for item in items],
+    }
+
+
+@router.post("/api/websites/{wid}/groups/organize", response_model=OrganizeGroupsResponse)
+def organize_website_groups(
+    wid: int,
+    db: Session = Depends(get_db),
+    _=Depends(get_current_user),
+):
+    """一键整理分组：按现有绑定关系导入/自愈账号（JSON 接口，兼容前端和测试）"""
+    ok, _organize_token = _try_start_task(wid, "organize")
+    if not ok:
+        raise HTTPException(409, "该网站的一键整理正在执行中")
+
+    logger.info("organize start wid=%s", wid)
+    t0 = time.monotonic()
+    items: list[OrganizeGroupsItem] = []
+    message = ""
+    success = False
+    try:
+        for event, data in _organize_website_groups_generator(wid, db):
+            if event == "item":
+                items.append(OrganizeGroupsItem(**data))
+            elif event == "complete":
+                success = data["success"]
+                message = data["message"]
+            elif event == "error":
+                if data["message"] == "website not found":
+                    raise HTTPException(404, "website not found")
+                if "only sub2api" in data["message"] or "目前只支持" in data["message"]:
+                    raise HTTPException(400, data["message"])
+                return OrganizeGroupsResponse(success=False, message=data["message"], items=[])
+    finally:
+        _finish_task(wid, "organize", _organize_token)
+
+    elapsed = time.monotonic() - t0
+    logger.info("organize complete wid=%s items=%d success=%s elapsed=%.1fs", wid, len(items), success, elapsed)
+    return OrganizeGroupsResponse(success=success, message=message, items=items)
+
+
+@router.post("/api/websites/{wid}/groups/organize/stream")
+def organize_website_groups_stream(
+    wid: int,
+    db: Session = Depends(get_db),
+    _=Depends(get_current_user),
+):
+    """流式一键整理分组"""
+
+    def event_generator():
+        ok, _organize_token = _try_start_task(wid, "organize")
+        if not ok:
+            yield json.dumps({"event": "error", "data": {"message": "该网站的一键整理正在执行中"}}, ensure_ascii=False) + "\n"
+            return
+
+        logger.info("organize/stream start wid=%s", wid)
+        t0 = time.monotonic()
+        for event, data in _with_background_heartbeat(
+            _organize_website_groups_generator, wid=wid, db=db,
+            task_wid=wid, task_type="organize", task_token=_organize_token,
+        ):
+            yield json.dumps({"event": event, "data": data}, ensure_ascii=False) + "\n"
+
+        elapsed = time.monotonic() - t0
+        logger.info("organize/stream complete wid=%s elapsed=%.1fs", wid, elapsed)
+
+    return StreamingResponse(
+        event_generator(),
+        media_type="application/x-ndjson",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+        },
     )
 
 
diff --git a/backend/test_background_heartbeat.py b/backend/test_background_heartbeat.py
new file mode 100644
index 0000000..f007849
--- /dev/null
+++ b/backend/test_background_heartbeat.py
@@ -0,0 +1,159 @@
+import time
+import threading
+from app.routers.websites import _with_background_heartbeat, _try_start_task, _finish_task
+import app.routers.websites as _websites_module
+
+
+def test_heartbeat_emitted_during_blocking_operation():
+    """生成器阻塞超过心跳间隔时，仍然能收到 heartbeat 事件。"""
+    # 模拟一个每 6 秒产生一条 item 的生成器
+    def slow_gen():
+        yield "item", {"n": 1}
+        time.sleep(7)  # 阻塞时间 > interval=4
+        yield "item", {"n": 2}
+        yield "complete", {"success": True, "message": "done"}
+
+    events = list(_with_background_heartbeat(slow_gen, interval=4, timeout_factor=5))
+
+    heartbeat_count = sum(1 for e, _ in events if e == "heartbeat")
+    assert heartbeat_count >= 1, f"阻塞 7s 应产生至少 1 个 heartbeat，实际 {heartbeat_count}"
+    items = [(e, d) for e, d in events if e == "item"]
+    assert len(items) == 2
+    assert items[0][1]["n"] == 1
+    assert items[1][1]["n"] == 2
+
+
+def test_heartbeat_multiple_during_long_block():
+    """长时间阻塞（>2 个心跳周期）时产生多个 heartbeat。"""
+    def long_block_gen():
+        yield "item", {"n": 1}
+        time.sleep(11)  # > 2 * interval=5
+        yield "complete", {"success": True, "message": "done"}
+
+    events = []
+    for event, data in _with_background_heartbeat(long_block_gen, interval=5, timeout_factor=5):
+        events.append(event)
+        if event == "complete":
+            break
+
+    heartbeat_count = sum(1 for e in events if e == "heartbeat")
+    assert heartbeat_count >= 2, f"11s 阻塞 (interval=5) 应产生至少 2 个 heartbeat，实际 {heartbeat_count}"
+
+
+def test_queue_full_does_not_deadlock():
+    """生产速度超过消费速度且队列满时，后台线程不会永久阻塞。"""
+    n_items = 300
+
+    def fast_gen():
+        for i in range(n_items):
+            yield "item", {"n": i}
+        yield "complete", {"success": True, "message": "done"}
+
+    # 使用大 timeout_factor 确保主线程有充足时间消费
+    events = list(_with_background_heartbeat(fast_gen, interval=10, timeout_factor=20))
+
+    item_count = sum(1 for e, _ in events if e == "item")
+    assert item_count == n_items, f"应有 {n_items} 个 item，实际 {item_count}"
+    assert any(e == "complete" for e, _ in events), "应收到 complete 事件"
+
+
+def test_generator_close_stops_background_thread_immediately():
+    """生成器关闭后后台线程停止，不阻塞 join 超时。"""
+    thread_done = threading.Event()
+
+    def infinite_gen():
+        try:
+            i = 0
+            while True:
+                yield "item", {"n": i}
+                i += 1
+        finally:
+            thread_done.set()
+
+    gen = _with_background_heartbeat(infinite_gen, interval=10, timeout_factor=10)
+
+    # 消费 3 个事件
+    count = 0
+    for event, data in gen:
+        count += 1
+        if count >= 3:
+            break
+
+    # 关闭生成器模拟客户端断开
+    gen.close()
+
+    # 后台线程应快速响应 cancel 并退出
+    assert thread_done.wait(timeout=10), "后台线程未在 10s 内停止"
+
+
+def test_worker_exception_caught_as_error_event():
+    """生成器内部抛出异常时，产生 error 事件而非崩溃。"""
+    def crashing_gen():
+        yield "item", {"n": 1}
+        raise RuntimeError("模拟意外错误")
+
+    events = list(_with_background_heartbeat(crashing_gen, interval=10, timeout_factor=5))
+
+    error_events = [(e, d) for e, d in events if e == "error"]
+    assert len(error_events) == 1
+    assert "模拟意外错误" in error_events[0][1]["message"]
+    # 不应收到 complete
+    assert not any(e == "complete" for e, _ in events)
+
+
+def test_worker_timeout_emits_error_and_cancels():
+    """worker 长时间不产生事件时，主线程超时并产生 error。"""
+    def stuck_gen():
+        yield "start", {}
+        time.sleep(15)  # 远远超过 queue.get 超时时间
+        yield "complete", {"success": True, "message": "done"}
+
+    # interval=5, timeout_factor=0.5 → queue.get 超时 = 2.5s
+    # 心跳间隔(5s) > queue.get 超时(2.5s)，所以不会因心跳重置超时计数器
+    events = list(_with_background_heartbeat(stuck_gen, interval=5, timeout_factor=0.5))
+
+    error_events = [(e, d) for e, d in events if e == "error"]
+    assert len(error_events) == 1
+    assert "长时间无响应" in error_events[0][1]["message"]
+
+
+def test_lock_held_until_worker_finishes_after_disconnect():
+    """生成器关闭后任务锁保持持有，直到业务线程真正退出。"""
+    wid = 9999
+
+    ok, _task_token = _try_start_task(wid, "test_lock")
+    assert ok, "应成功获取锁"
+
+    worker_done = threading.Event()
+
+    def blocking_gen():
+        try:
+            yield "item", {"n": 1}
+            time.sleep(5)  # 模拟长时间阻塞（HTTP 请求等）
+            yield "complete", {"success": True, "message": "done"}
+        finally:
+            worker_done.set()
+
+    gen = _with_background_heartbeat(
+        blocking_gen, interval=10, timeout_factor=10,
+        task_wid=wid, task_type="test_lock", task_token=_task_token,
+    )
+
+    # 消费一个 item 后关闭生成器（模拟客户端断开）
+    next(gen)
+    gen.close()
+
+    # 关闭后锁应当仍然被持有（worker 还在 sleep(5) 中）
+    ok, _ = _try_start_task(wid, "test_lock")
+    assert not ok, "断开后锁应继续保持持有"
+
+    # 等待 worker 真正结束
+    assert worker_done.wait(timeout=10), "worker 未在预期时间内结束"
+
+    # worker 结束后，_finish_task 已在 _run() 的 finally 中执行，
+    # 新请求应能获取锁
+    ok, _ = _try_start_task(wid, "test_lock")
+    assert ok, "worker 结束后应能重新获取锁"
+
+    # 清理
+    _finish_task(wid, "test_lock", _task_token)
diff --git a/backend/test_organize_groups.py b/backend/test_organize_groups.py
index ac11de4..1034832 100644
--- a/backend/test_organize_groups.py
+++ b/backend/test_organize_groups.py
@@ -327,9 +327,347 @@ def test_organize_groups_list_accounts_none_conservatively_skips(db_session, mon
     assert k3.status == "imported"
 
 
+def test_organize_groups_streaming_basic_event_sequence(db_session, monkeypatch):
+    """流式一键整理：验证基本 NDJSON 事件序列、响应头、total_items 准确性。"""
+    w = Website(
+        name="W1",
+        site_type="sub2api",
+        base_url="http://w1",
+        enabled=True,
+        auth_config_json="{}",
+        timeout_seconds=30
+    )
+    u1 = Upstream(name="U1", base_url="http://u1")
+    db_session.add_all([w, u1])
+    db_session.commit()
+    db_session.refresh(w)
+    db_session.refresh(u1)
+
+    b1 = WebsiteGroupBinding(
+        website_id=w.id,
+        target_group_id="TG1",
+        target_group_name="TG1-Group",
+        source_groups_json=json.dumps([
+            {"upstream_id": u1.id, "group_id": "G1"},
+        ]),
+        enabled=True
+    )
+    db_session.add(b1)
+
+    k1 = UpstreamGeneratedKey(
+        upstream_id=u1.id,
+        group_id="G1",
+        group_name="G1-Name",
+        key_name="Key-G1",
+        key_value="sk-g1-secret",
+        status="created",
+    )
+    db_session.add(k1)
+    db_session.commit()
+
+    created_accounts = []
+
+    class MockClient:
+        def __init__(self, **kwargs): pass
+        def __enter__(self): return self
+        def __exit__(self, *a): pass
+        def get_groups(self, *a, **kw):
+            return [{"id": "TG1", "name": "TG1-Group"}]
+        def list_accounts(self): return []
+        def extract_id(self, val): return val.get("id") if isinstance(val, dict) else str(val)
+        def create_account(self, body):
+            acc_id = f"NEW-{body['name']}"
+            new_acc = {"id": acc_id, "name": body["name"], "group_ids": body["group_ids"]}
+            created_accounts.append(new_acc)
+            return new_acc
+
+    monkeypatch.setattr("app.routers.websites.Sub2ApiWebsiteClient", MockClient)
+    monkeypatch.setattr("app.routers.websites.sync_account_priorities_for_website", lambda db, wid: [])
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        resp = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+        assert resp.status_code == 200
+        assert resp.headers["content-type"] == "application/x-ndjson"
+        assert resp.headers.get("cache-control") == "no-cache"
+        assert resp.headers.get("x-accel-buffering") == "no"
+
+        lines = [line if isinstance(line, str) else line.decode("utf-8") for line in resp.iter_lines() if line]
+        parsed_events = [json.loads(line) for line in lines]
+
+        # Event sequence: start → item → complete
+        assert len(parsed_events) >= 2
+        assert parsed_events[0]["event"] == "start"
+        assert parsed_events[0]["data"]["total_items"] == 1
+
+        item_events = [e for e in parsed_events if e["event"] == "item"]
+        assert len(item_events) == 1
+        assert item_events[0]["data"]["source_group_id"] == "G1"
+        assert item_events[0]["data"]["status"] == "created"
+
+        complete_event = next(e for e in parsed_events if e["event"] == "complete")
+        assert complete_event["data"]["success"] is True
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_organize_groups_streaming_409_concurrent_lock(db_session, monkeypatch):
+    """流式一键整理：同一网站并发调用返回 409 错误。"""
+    w = Website(
+        name="W1",
+        site_type="sub2api",
+        base_url="http://w1",
+        enabled=True,
+        auth_config_json="{}",
+        timeout_seconds=30
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    # Mock to make the first call run long enough to trigger concurrency
+    import time
+    original_generator = None
+
+    class MockClient:
+        def __init__(self, **kwargs): pass
+        def __enter__(self): return self
+        def __exit__(self, *a): pass
+        def get_groups(self, *a, **kw): return [{"id": "TG1", "name": "TG1-Group"}]
+        def list_accounts(self): return []
+        def extract_id(self, val): return val.get("id") if isinstance(val, dict) else str(val)
+
+    monkeypatch.setattr("app.routers.websites.Sub2ApiWebsiteClient", MockClient)
+    monkeypatch.setattr("app.routers.websites.sync_account_priorities_for_website", lambda db, wid: [])
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        # First request starts the task lock
+        resp1 = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+        assert resp1.status_code == 200
+
+        # Second request while first is still "running" (lock not yet released)
+        # But the first request already completed, so we need to simulate
+        # by calling the task lock manually.
+        from app.routers.websites import _try_start_task, _finish_task
+        ok, _task_token = _try_start_task(w.id, "organize")
+        assert ok
+        try:
+            resp2 = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+            assert resp2.status_code == 200
+            lines = [line if isinstance(line, str) else line.decode("utf-8") for line in resp2.iter_lines() if line]
+            parsed_events = [json.loads(line) for line in lines]
+            assert len(parsed_events) == 1
+            assert parsed_events[0]["event"] == "error"
+            assert "正在执行中" in parsed_events[0]["data"]["message"]
+        finally:
+            _finish_task(w.id, "organize", _task_token)
+
+        # Task lock released: third request should succeed
+        resp3 = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+        assert resp3.status_code == 200
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_organize_groups_streaming_non_sub2api_returns_error_event(db_session, monkeypatch):
+    """流式一键整理：非 sub2api 网站返回 error 事件而非 HTTP 错误。"""
+    w = Website(
+        name="W1",
+        site_type="other",
+        base_url="http://w1",
+        enabled=True,
+        auth_config_json="{}",
+        timeout_seconds=30
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        resp = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+        assert resp.status_code == 200
+        lines = [line if isinstance(line, str) else line.decode("utf-8") for line in resp.iter_lines() if line]
+        parsed_events = [json.loads(line) for line in lines]
+        assert len(parsed_events) == 1
+        assert parsed_events[0]["event"] == "error"
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_organize_groups_streaming_total_items_matches_items(db_session, monkeypatch):
+    """流式一键整理：total_items 应当等于实际产生的 item 数量。"""
+    w = Website(
+        name="W1",
+        site_type="sub2api",
+        base_url="http://w1",
+        enabled=True,
+        auth_config_json="{}",
+        timeout_seconds=30
+    )
+    u1 = Upstream(name="U1", base_url="http://u1")
+    db_session.add_all([w, u1])
+    db_session.commit()
+    db_session.refresh(w)
+    db_session.refresh(u1)
+
+    # Two bindings, each with one key
+    b1 = WebsiteGroupBinding(
+        website_id=w.id,
+        target_group_id="TG1",
+        target_group_name="TG1-Group",
+        source_groups_json=json.dumps([{"upstream_id": u1.id, "group_id": "G1"}]),
+        enabled=True
+    )
+    b2 = WebsiteGroupBinding(
+        website_id=w.id,
+        target_group_id="TG2",
+        target_group_name="TG2-Group",
+        source_groups_json=json.dumps([{"upstream_id": u1.id, "group_id": "G2"}]),
+        enabled=True
+    )
+    db_session.add_all([b1, b2])
+
+    k1 = UpstreamGeneratedKey(
+        upstream_id=u1.id, group_id="G1", group_name="G1-Name",
+        key_name="Key-G1", key_value="sk-g1", status="created",
+    )
+    k2 = UpstreamGeneratedKey(
+        upstream_id=u1.id, group_id="G2", group_name="G2-Name",
+        key_name="Key-G2", key_value="sk-g2", status="created",
+    )
+    db_session.add_all([k1, k2])
+    db_session.commit()
+
+    class MockClient:
+        def __init__(self, **kwargs): pass
+        def __enter__(self): return self
+        def __exit__(self, *a): pass
+        def get_groups(self, *a, **kw):
+            return [{"id": "TG1", "name": "TG1-Group"}, {"id": "TG2", "name": "TG2-Group"}]
+        def list_accounts(self): return []
+        def extract_id(self, val): return val.get("id") if isinstance(val, dict) else str(val)
+        def create_account(self, body):
+            return {"id": "NEW-" + body["name"], "name": body["name"], "group_ids": body["group_ids"]}
+
+    monkeypatch.setattr("app.routers.websites.Sub2ApiWebsiteClient", MockClient)
+    monkeypatch.setattr("app.routers.websites.sync_account_priorities_for_website", lambda db, wid: [])
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        resp = client.post(f"/api/websites/{w.id}/groups/organize/stream")
+        assert resp.status_code == 200
+        lines = [line if isinstance(line, str) else line.decode("utf-8") for line in resp.iter_lines() if line]
+        parsed_events = [json.loads(line) for line in lines]
+
+        start_event = next(e for e in parsed_events if e["event"] == "start")
+        item_events = [e for e in parsed_events if e["event"] == "item"]
+        assert start_event["data"]["total_items"] == len(item_events)
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_organize_groups_original_json_endpoint_still_works(db_session, monkeypatch):
+    """一键整理 JSON 接口的回归测试：HTTP 状态码和错误处理仍然正确。"""
+    # Non-sub2api → HTTP 400
+    w = Website(
+        name="W1", site_type="other", base_url="http://w1",
+        enabled=True, auth_config_json="{}", timeout_seconds=30
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        resp = client.post(f"/api/websites/{w.id}/groups/organize")
+        assert resp.status_code == 400
+        assert "只支持" in resp.json()["detail"] or "only sub2api" in resp.json()["detail"]
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_organize_groups_json_409_concurrent_lock(db_session, monkeypatch):
+    """一键整理 JSON 接口：并发调用返回 HTTP 409。"""
+    w = Website(
+        name="W1", site_type="sub2api", base_url="http://w1",
+        enabled=True, auth_config_json="{}", timeout_seconds=30,
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        # Hold lock manually to simulate concurrent request
+        from app.routers.websites import _try_start_task, _finish_task
+        ok, _task_token = _try_start_task(w.id, "organize")
+        assert ok
+        try:
+            resp = client.post(f"/api/websites/{w.id}/groups/organize")
+            assert resp.status_code == 409
+            assert "正在执行中" in resp.json()["detail"]
+        finally:
+            _finish_task(w.id, "organize", _task_token)
+
+        # Lock released: second request should succeed
+        resp2 = client.post(f"/api/websites/{w.id}/groups/organize")
+        assert resp2.status_code == 200
+    finally:
+        app.dependency_overrides.clear()
+
+
 def test_organize_groups_force_alignment(db_session, monkeypatch):
     """测试强对齐场景：
-    1. 已存在账号在旧 SmartUp 分组，整理后移除旧分组并加入新分组。
     2. 已存在账号同时有非 SmartUp 分组，整理后保留非 SmartUp 分组。
     3. 已存在账号已经完全一致，整理不重复调用更新接口。
     4. 多目标分组、多上游来源时，每个账号按自己的当前绑定关系对齐。
diff --git a/backend/test_sync_upstream_models.py b/backend/test_sync_upstream_models.py
index b7d242e..ba9a11e 100644
--- a/backend/test_sync_upstream_models.py
+++ b/backend/test_sync_upstream_models.py
@@ -408,3 +408,79 @@ def test_sync_upstream_models_empty_key_value_skips_account(db_session, monkeypa
         assert len(update_calls) == 0, f"不应调用 update_account，实际调用：{update_calls}"
     finally:
         app.dependency_overrides.clear()
+
+
+def test_sync_upstream_models_concurrent_lock_json_endpoint(db_session, monkeypatch):
+    """同步上游模型 JSON 接口：并发调用返回 HTTP 409。"""
+    w = Website(
+        name="W1", site_type="sub2api", base_url="http://w1",
+        enabled=True, auth_config_json="{}", timeout_seconds=30,
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        from app.routers.websites import _try_start_task, _finish_task
+        ok, _sync_token = _try_start_task(w.id, "sync_models")
+        assert ok
+        try:
+            resp = client.post(f"/api/websites/{w.id}/accounts/sync-upstream-models")
+            assert resp.status_code == 409
+            assert "正在执行中" in resp.json()["detail"]
+        finally:
+            _finish_task(w.id, "sync_models", _sync_token)
+
+        resp2 = client.post(f"/api/websites/{w.id}/accounts/sync-upstream-models")
+        assert resp2.status_code == 200
+    finally:
+        app.dependency_overrides.clear()
+
+
+def test_sync_upstream_models_concurrent_lock_stream_endpoint(db_session, monkeypatch):
+    """同步上游模型流式接口：并发调用返回 error 事件。"""
+    w = Website(
+        name="W1", site_type="sub2api", base_url="http://w1",
+        enabled=True, auth_config_json="{}", timeout_seconds=30,
+    )
+    db_session.add(w)
+    db_session.commit()
+    db_session.refresh(w)
+
+    from fastapi.testclient import TestClient
+    from app.main import app
+    from app.database import get_db
+    from app.utils.auth import get_current_user
+
+    app.dependency_overrides[get_db] = lambda: db_session
+    app.dependency_overrides[get_current_user] = lambda: None
+
+    try:
+        client = TestClient(app)
+        from app.routers.websites import _try_start_task, _finish_task
+        ok, _sync_token = _try_start_task(w.id, "sync_models")
+        assert ok
+        try:
+            resp = client.post(f"/api/websites/{w.id}/accounts/sync-upstream-models/stream")
+            assert resp.status_code == 200
+            lines = [line if isinstance(line, str) else line.decode("utf-8") for line in resp.iter_lines() if line]
+            parsed_events = [json.loads(line) for line in lines]
+            assert len(parsed_events) == 1
+            assert parsed_events[0]["event"] == "error"
+            assert "正在执行中" in parsed_events[0]["data"]["message"]
+        finally:
+            _finish_task(w.id, "sync_models", _sync_token)
+
+        resp2 = client.post(f"/api/websites/{w.id}/accounts/sync-upstream-models/stream")
+        assert resp2.status_code == 200
+    finally:
+        app.dependency_overrides.clear()
diff --git a/frontend/src/api/index.ts b/frontend/src/api/index.ts
index 48e7f9f..c5769b1 100644
--- a/frontend/src/api/index.ts
+++ b/frontend/src/api/index.ts
@@ -67,6 +67,117 @@ export const authApi = {
   me: () => api.get<{ email: string }>('/api/auth/me'),
 }
 
+// ——— NDJSON 流式读取工具 ———
+export type NdjsonEvent = {
+  event: string
+  data: Record<string, unknown>
+}
+
+export type NdjsonStreamHandlers = {
+  onStart?: (data: Record<string, unknown>) => void
+  onItem?: (data: Record<string, unknown>) => void
+  onComplete?: (data: Record<string, unknown>) => void
+  onError?: (data: Record<string, unknown>) => void
+  onHeartbeat?: () => void
+}
+
+/**
+ * 读取 NDJSON 流，按 event 类型分派处理器。
+ * 返回 { ok, message }，ok=false 表示流未正常完成（含 HTTP 错误、解析错误、断流）。
+ */
+export async function readNdjsonStream(
+  url: string,
+  options: RequestInit & { token?: string },
+  handlers: NdjsonStreamHandlers,
+): Promise<{ ok: boolean; message: string }> {
+  const { token, ...fetchOpts } = options
+  const headers: Record<string, string> = {
+    'Content-Type': 'application/json',
+    ...((fetchOpts.headers as Record<string, string>) || {}),
+  }
+  if (token) {
+    headers['Authorization'] = `Bearer ${token}`
+  }
+
+  let response: Response
+  try {
+    response = await fetch(url, { ...fetchOpts, headers })
+  } catch (e: any) {
+    return { ok: false, message: e.message || '网络请求失败' }
+  }
+
+  if (!response.ok) {
+    let errMsg = `请求失败 (${response.status})`
+    try {
+      const errJson = await response.json()
+      if (errJson?.detail) errMsg = errJson.detail
+    } catch {}
+    return { ok: false, message: errMsg }
+  }
+
+  const reader = response.body?.getReader()
+  if (!reader) {
+    return { ok: false, message: '无法读取响应流' }
+  }
+
+  const decoder = new TextDecoder()
+  let buffer = ''
+  let gotComplete = false
+
+  try {
+    while (true) {
+      const { done, value } = await reader.read()
+      if (done) break
+
+      buffer += decoder.decode(value, { stream: true })
+      const lines = buffer.split('\n')
+      buffer = lines.pop() || ''
+
+      for (const line of lines) {
+        if (!line.trim()) continue
+        let parsed: NdjsonEvent
+        try {
+          parsed = JSON.parse(line)
+        } catch {
+          continue
+        }
+        const { event, data } = parsed
+        if (event === 'start') handlers.onStart?.(data)
+        else if (event === 'item') handlers.onItem?.(data)
+        else if (event === 'complete') {
+          handlers.onComplete?.(data)
+          gotComplete = true
+        } else if (event === 'error') handlers.onError?.(data)
+        else if (event === 'heartbeat') handlers.onHeartbeat?.()
+      }
+    }
+
+    // 处理尾部缓冲
+    if (buffer.trim()) {
+      try {
+        const parsed = JSON.parse(buffer)
+        const { event, data } = parsed
+        if (event === 'complete') {
+          handlers.onComplete?.(data)
+          gotComplete = true
+        } else if (event === 'error') {
+          handlers.onError?.(data)
+        } else if (event === 'item') {
+          handlers.onItem?.(data)
+        }
+      } catch {}
+    }
+
+    if (!gotComplete) {
+      return { ok: false, message: '流异常中断，未获取到完整执行报告' }
+    }
+  } catch (e: any) {
+    return { ok: false, message: e.message || '流读取异常' }
+  }
+
+  return { ok: true, message: '' }
+}
+
 // ——— Upstreams ———
 export type FinanceCostMode = 'usage_stats' | 'balance_delta'
 
diff --git a/frontend/src/views/Websites.vue b/frontend/src/views/Websites.vue
index cfe136f..3f60971 100644
--- a/frontend/src/views/Websites.vue
+++ b/frontend/src/views/Websites.vue
@@ -751,55 +751,80 @@
       </template>
     </el-dialog>
 
-    <el-dialog v-model="organizeDialog" title="一键整理分组结果" width="850px" destroy-on-close>
-      <div v-if="organizeMessage" style="margin-bottom:12px; font-weight:bold; color:var(--el-color-primary)">
-        {{ organizeMessage }}
+    <el-dialog
+      v-model="organizeDialog"
+      title="一键整理分组结果"
+      width="850px"
+      destroy-on-close
+      :show-close="!organizeLoading"
+      :close-on-click-modal="!organizeLoading"
+      :close-on-press-escape="!organizeLoading"
+      :before-close="handleOrganizeDialogBeforeClose"
+    >
+      <div>
+        <div style="margin-bottom: 15px; display: flex; align-items: center; justify-content: space-between; font-size: 14px;">
+          <div>
+            <span style="margin-right: 15px;">已处理: <strong style="color: var(--el-color-primary);">{{ organizeProcessedCount }}{{ organizeTotal ? '/' + organizeTotal : '' }}</strong></span>
+            <span style="margin-right: 15px;">成功: <strong style="color: var(--el-color-success);">{{ organizeSuccessCount }}</strong></span>
+            <span style="margin-right: 15px;">跳过: <strong style="color: var(--el-color-warning);">{{ organizeSkippedCount }}</strong></span>
+            <span style="margin-right: 15px;">失败: <strong style="color: var(--el-color-danger);">{{ organizeFailedCount }}</strong></span>
+          </div>
+          <div v-if="organizeLoading" style="color: var(--el-color-info); display: flex; align-items: center;">
+            <span class="is-loading" style="margin-right: 5px; display: inline-flex;"><el-icon><Refresh /></el-icon></span>
+            正在整理分组...
+          </div>
+        </div>
+
+        <div v-if="organizeMessage" style="margin-bottom:12px; font-weight:bold; color:var(--el-color-primary)">
+          {{ organizeMessage }}
+        </div>
+
+        <el-table :data="organizeResults" size="small" border style="width:100%; max-height: 400px; overflow-y: auto;">
+          <el-table-column label="目标分组" min-width="150">
+            <template #default="{ row }">
+              <div>{{ row.target_group_name }}</div>
+              <div style="font-size:11px;color:var(--text-muted)">ID: {{ row.target_group_id }}</div>
+            </template>
+          </el-table-column>
+          <el-table-column label="来源上游/分组" min-width="165">
+            <template #default="{ row }">
+              <div>{{ row.upstream_name }}</div>
+              <div style="font-size:11px;color:var(--text-muted)">{{ row.source_group_name }} (ID: {{ row.source_group_id }})</div>
+            </template>
+          </el-table-column>
+          <el-table-column label="上游 Key" min-width="140">
+            <template #default="{ row }">
+              <span v-if="row.key_name">{{ row.key_name }}</span>
+              <span v-else class="muted">—</span>
+            </template>
+          </el-table-column>
+          <el-table-column label="目标账号" min-width="150">
+            <template #default="{ row }">
+              <div v-if="row.account_id">
+                <div>{{ row.account_name }}</div>
+                <div style="font-size:11px;color:var(--text-muted)">ID: {{ row.account_id }}</div>
+              </div>
+              <span v-else class="muted">—</span>
+            </template>
+          </el-table-column>
+          <el-table-column label="状态" width="110">
+            <template #default="{ row }">
+              <el-tag v-if="row.status === 'created'" size="small" type="success">已创建</el-tag>
+              <el-tag v-else-if="row.status === 'recreated'" size="small" type="warning">清理后重建</el-tag>
+              <el-tag v-else-if="row.status === 'exists'" size="small" type="info">已存在</el-tag>
+              <el-tag v-else-if="row.status === 'missing_key'" size="small" type="danger">缺少 Key</el-tag>
+              <el-tag v-else size="small" type="danger">{{ keyStatusLabel(row.status) }}</el-tag>
+            </template>
+          </el-table-column>
+          <el-table-column prop="message" label="说明/原因" min-width="150">
+            <template #default="{ row }">
+              <span :class="{ 'error-text': row.status === 'failed' }">{{ row.message }}</span>
+            </template>
+          </el-table-column>
+        </el-table>
       </div>
-      <el-table :data="organizeResults" size="small" border style="width:100%">
-        <el-table-column label="目标分组" min-width="150">
-          <template #default="{ row }">
-            <div>{{ row.target_group_name }}</div>
-            <div style="font-size:11px;color:var(--text-muted)">ID: {{ row.target_group_id }}</div>
-          </template>
-        </el-table-column>
-        <el-table-column label="来源上游/分组" min-width="165">
-          <template #default="{ row }">
-            <div>{{ row.upstream_name }}</div>
-            <div style="font-size:11px;color:var(--text-muted)">{{ row.source_group_name }} (ID: {{ row.source_group_id }})</div>
-          </template>
-        </el-table-column>
-        <el-table-column label="上游 Key" min-width="140">
-          <template #default="{ row }">
-            <span v-if="row.key_name">{{ row.key_name }}</span>
-            <span v-else class="muted">—</span>
-          </template>
-        </el-table-column>
-        <el-table-column label="目标账号" min-width="150">
-          <template #default="{ row }">
-            <div v-if="row.account_id">
-              <div>{{ row.account_name }}</div>
-              <div style="font-size:11px;color:var(--text-muted)">ID: {{ row.account_id }}</div>
-            </div>
-            <span v-else class="muted">—</span>
-          </template>
-        </el-table-column>
-        <el-table-column label="状态" width="110">
-          <template #default="{ row }">
-            <el-tag v-if="row.status === 'created'" size="small" type="success">已创建</el-tag>
-            <el-tag v-else-if="row.status === 'recreated'" size="small" type="warning">清理后重建</el-tag>
-            <el-tag v-else-if="row.status === 'exists'" size="small" type="info">已存在</el-tag>
-            <el-tag v-else-if="row.status === 'missing_key'" size="small" type="danger">缺少 Key</el-tag>
-            <el-tag v-else size="small" type="danger">{{ keyStatusLabel(row.status) }}</el-tag>
-          </template>
-        </el-table-column>
-        <el-table-column prop="message" label="说明/原因" min-width="150">
-          <template #default="{ row }">
-            <span :class="{ 'error-text': row.status === 'failed' }">{{ row.message }}</span>
-          </template>
-        </el-table-column>
-      </el-table>
       <template #footer>
-        <el-button @click="organizeDialog = false">关闭</el-button>
+        <el-button @click="organizeDialog = false" :disabled="organizeLoading">关闭</el-button>
       </template>
     </el-dialog>
 
@@ -1125,6 +1150,7 @@ import {
   type CleanupInvalidAccountsItem,
   type SetConcurrencyItem,
   type SyncUpstreamModelsItem,
+  readNdjsonStream,
 } from '@/api'
 
 const websites = ref<(WebsiteData & { _testing?: boolean })[]>([])
@@ -1276,6 +1302,18 @@ const organizeDialog = ref(false)
 const organizeLoading = ref(false)
 const organizeResults = ref<OrganizeGroupsItem[]>([])
 const organizeMessage = ref('')
+const organizeTotal = ref(0)
+const organizeSuccessCount = computed(() => organizeResults.value.filter(r => r.status === 'created' || r.status === 'recreated' || r.status === 'exists').length)
+const organizeFailedCount = computed(() => organizeResults.value.filter(r => r.status === 'failed').length)
+const organizeSkippedCount = computed(() => organizeResults.value.filter(r => r.status === 'missing_key').length)
+const organizeProcessedCount = computed(() => organizeResults.value.length)
+
+function handleOrganizeDialogBeforeClose(done: () => void) {
+  if (organizeLoading.value) {
+    return
+  }
+  done()
+}
 
 const cleanupDialog = ref(false)
 const cleanupLoading = ref(false)
@@ -1971,19 +2009,42 @@ async function organizeWebsiteGroups() {
     return
   }
 
+  organizeResults.value = []
+  organizeMessage.value = ''
+  organizeTotal.value = 0
   organizeLoading.value = true
-  try {
-    const res = await websitesApi.organizeGroups(selectedWebsite.value.id)
-    organizeMessage.value = res.data.message
-    organizeResults.value = res.data.items
-    organizeDialog.value = true
+  organizeDialog.value = true
+
+  const authStore = useAuthStore()
+  const { ok, message } = await readNdjsonStream(
+    `/api/websites/${selectedWebsite.value.id}/groups/organize/stream`,
+    { method: 'POST', token: authStore.token },
+    {
+      onStart(data) { organizeTotal.value = (data.total_items as number) || 0 },
+      onItem(data: any) { organizeResults.value.push(data) },
+      onComplete(data) {
+        organizeMessage.value = (data.message as string) || ''
+        if (data.success) ElMessage.success('整理完成')
+        else ElMessage.warning((data.message as string) || '部分账号整理失败')
+      },
+      onError(data) { throw new Error((data.message as string) || '流式整理出错') },
+    },
+  )
+
+  if (!ok) {
+    if (message.includes('正在执行中')) {
+      ElMessage.warning(message)
+    } else {
+      ElMessage.error(message || '一键整理分组失败')
+    }
+    if (organizeResults.value.length === 0) {
+      organizeDialog.value = false
+    }
+  } else {
     // 刷新相关数据
     await Promise.all([loadLogs(), loadWebsiteGroups(), loadBindings()])
-  } catch (e: any) {
-    ElMessage.error(e.response?.data?.detail || '一键整理分组失败')
-  } finally {
-    organizeLoading.value = false
   }
+  organizeLoading.value = false
 }
 
 async function openCleanupDialog() {
@@ -2127,105 +2188,37 @@ async function triggerSyncUpstreamModels() {
   syncModelsDialog.value = true
 
   let hasProcessedStart = false
-  let gotComplete = false
 
-  try {
-    const authStore = useAuthStore()
-    const headers: Record<string, string> = {
-      'Content-Type': 'application/json',
-    }
-    if (authStore.token) {
-      headers['Authorization'] = `Bearer ${authStore.token}`
-    }
-
-    const response = await fetch(`/api/websites/${selectedWebsite.value.id}/accounts/sync-upstream-models/stream`, {
-      method: 'POST',
-      headers,
-    })
-
-    if (!response.ok) {
-      let errMsg = `请求失败 (${response.status})`
-      try {
-        const errJson = await response.json()
-        if (errJson?.detail) errMsg = errJson.detail
-      } catch {}
-      throw new Error(errMsg)
-    }
-
-    const reader = response.body?.getReader()
-    if (!reader) {
-      throw new Error('无法读取响应流')
-    }
-
-    const decoder = new TextDecoder()
-    let buffer = ''
-
-    while (true) {
-      const { done, value } = await reader.read()
-      if (done) {
-        break
-      }
-
-      buffer += decoder.decode(value, { stream: true })
-      const lines = buffer.split('\n')
-      buffer = lines.pop() || ''
-
-      for (const line of lines) {
-        if (!line.trim()) continue
-        const eventObj = JSON.parse(line)
-        const { event, data } = eventObj
-
-        if (event === 'start') {
-          syncModelsTotal.value = data.total_accounts || 0
-          hasProcessedStart = true
-        } else if (event === 'item') {
-          syncModelsResults.value.push(data)
-        } else if (event === 'complete') {
-          syncModelsMessage.value = data.message
-          gotComplete = true
-          if (data.success) {
-            ElMessage.success('同步完成')
-          } else {
-            ElMessage.warning(data.message || '部分账号同步模型失败')
-          }
-        } else if (event === 'error') {
-          throw new Error(data.message || '流式同步出错')
-        }
-      }
-    }
-
-    if (buffer.trim()) {
-      const eventObj = JSON.parse(buffer)
-      const { event, data } = eventObj
-      if (event === 'start') {
-        syncModelsTotal.value = data.total_accounts || 0
+  const authStore = useAuthStore()
+  const { ok, message } = await readNdjsonStream(
+    `/api/websites/${selectedWebsite.value.id}/accounts/sync-upstream-models/stream`,
+    { method: 'POST', token: authStore.token },
+    {
+      onStart(data) {
+        syncModelsTotal.value = (data.total_accounts as number) || 0
         hasProcessedStart = true
-      } else if (event === 'item') {
-        syncModelsResults.value.push(data)
-      } else if (event === 'complete') {
-        syncModelsMessage.value = data.message
-        gotComplete = true
-        if (data.success) {
-          ElMessage.success('同步完成')
-        } else {
-          ElMessage.warning(data.message || '部分账号同步模型失败')
-        }
-      } else if (event === 'error') {
-        throw new Error(data.message || '流式同步出错')
-      }
-    }
+      },
+      onItem(data: any) { syncModelsResults.value.push(data) },
+      onComplete(data) {
+        syncModelsMessage.value = (data.message as string) || ''
+        if (data.success) ElMessage.success('同步完成')
+        else ElMessage.warning((data.message as string) || '部分账号同步模型失败')
+      },
+      onError() { /* handled via !ok */ },
+    },
+  )
 
-    if (!gotComplete) {
-      throw new Error('同步流异常中断，未获取到完整执行报告')
+  if (!ok) {
+    if (message.includes('正在执行中')) {
+      ElMessage.warning(message)
+    } else {
+      ElMessage.error(message || '同步上游模型失败')
     }
-  } catch (e: any) {
-    ElMessage.error(e.message || '同步上游模型失败')
     if (!hasProcessedStart || syncModelsResults.value.length === 0) {
       syncModelsDialog.value = false
     }
-  } finally {
-    syncModelsExecuting.value = false
   }
+  syncModelsExecuting.value = false
 }
 
 async function toggleBinding(row: GroupBindingData) {