fix memory usage redis

tests/test_redis_service.py

@@ -18,7 +18,7 @@ def test_redis_uses_aof_everysec_and_rdb_snapshot():
         assert cmd[cmd.index("--appendfsync") + 1] == "everysec"
         assert cmd[cmd.index("--save") + 1:cmd.index("--save") + 3] == ["900", "100"]
         assert cmd[cmd.index("--dir") + 1] == td
-        assert cmd[cmd.index("--maxmemory") + 1] == "0"
+        assert cmd[cmd.index("--maxmemory") + 1] == "128mb"
         assert cmd[cmd.index("--maxmemory-policy") + 1] == "noeviction"
 
 
@@ -32,3 +32,19 @@ def test_redis_status_exposes_runtime_details_for_system_ui():
         assert status["data_dir"] == td
         assert status["snapshot_seconds"] == 1200
         assert status["persistence"] == "AOF everysec + RDB"
+
+
+def test_redis_defaults_to_bounded_transient_buffer():
+    with tempfile.TemporaryDirectory() as td:
+        supervisor = RedisSupervisor(True, td, port=6382)
+        supervisor.executable = "/usr/bin/redis-server"
+        with patch("app.redis_service.subprocess.Popen") as popen:
+            process = popen.return_value
+            process.poll.return_value = None
+            process.pid = 124
+            supervisor._spawn()
+            cmd = popen.call_args.args[0]
+        assert cmd[cmd.index("--appendonly") + 1] == "no"
+        assert cmd[cmd.index("--save") + 1] == ""
+        assert cmd[cmd.index("--maxmemory") + 1] == "128mb"
+        assert supervisor.status()["persistence"] == "disabled (SQLite archive is durable)"