fix: avoid SQLite lock on fast position poll by skipping DB writes

Co-authored-by: Cursor <cursoragent@cursor.com>

db_conn.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 
 import os
 import sqlite3
+import time
 
 DB_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)), "futures.db")
 
@@ -17,3 +18,27 @@ def connect_db(path: str | None = None) -> sqlite3.Connection:
     except sqlite3.OperationalError:
         pass
     return conn
+
+
+def execute_retry(
+    conn: sqlite3.Connection,
+    sql: str,
+    params: tuple = (),
+    *,
+    retries: int = 6,
+    base_delay: float = 0.05,
+) -> sqlite3.Cursor:
+    """遇 database is locked 时短暂退避重试。"""
+    last_exc: Exception | None = None
+    for attempt in range(retries):
+        try:
+            return conn.execute(sql, params)
+        except sqlite3.OperationalError as exc:
+            if "locked" not in str(exc).lower():
+                raise
+            last_exc = exc
+            if attempt < retries - 1:
+                time.sleep(base_delay * (attempt + 1))
+    if last_exc:
+        raise last_exc
+    raise sqlite3.OperationalError("database is locked")

install_trading.py

@@ -33,6 +33,7 @@ from position_stream import position_hub, start_position_worker
 from ctp_reconnect import start_ctp_reconnect_worker
 from ctp_premarket_connect import start_ctp_premarket_connect_worker
 from ctp_fee_worker import start_ctp_fee_worker
+from db_conn import execute_retry
 from sl_tp_guard import (
     cancel_monitor_exit_orders,
     ensure_monitor_order_columns,
@@ -480,7 +481,8 @@ def install_trading(app, *, login_required, require_nav, get_db, get_setting, se
                     open_time_val = ctp_open
             elif ctp_open:
                 open_time_val = ctp_open
-            conn.execute(
+            execute_retry(
+                conn,
                 """UPDATE trade_order_monitors SET lots=?, entry_price=?,
                    open_time=? WHERE id=?""",
                 (
@@ -684,7 +686,7 @@ def install_trading(app, *, login_required, require_nav, get_db, get_setting, se
                         break
             elif key in ctp_by_key:
                 used_ctp_keys.add(key)
-            if ctp and mon:
+            if ctp and mon and not fast:
                 _sync_monitor_lots_from_ctp(
                     conn, int(mon["id"]), mon.get("symbol") or "",
                     mon.get("direction") or "long", mode, ctp=ctp,
@@ -896,7 +898,6 @@ def install_trading(app, *, login_required, require_nav, get_db, get_setting, se
         try:
             init_strategy_tables(conn)
             payload = _build_trading_live_payload(conn, fast=True)
-            conn.commit()
             position_hub.set_snapshot(payload)
             return jsonify(payload)
         finally:

sl_tp_guard.py

@@ -606,12 +606,13 @@ def check_monitors_locally(
     if not is_trading_session():
         return 0
     reconcile_monitors_without_position(conn, mode)
+    conn.commit()
     closed = 0
-    rows = conn.execute(
+    rows = [dict(r) for r in conn.execute(
         "SELECT * FROM trade_order_monitors WHERE status='active'"
-    ).fetchall()
-    for r in rows:
-        mon = dict(r)
+    ).fetchall()]
+    conn.commit()
+    for mon in rows:
         mid = int(mon.get("id") or 0)
         sym = (mon.get("symbol") or "").strip()
         direction = (mon.get("direction") or "long").strip().lower()