# [Critical bug] TiKV may fail to restart in 6.5.4 if Titan is enabled

## Issue

问题描述 问题发现于： [ISSUE 15459](https://github.com/tikv/tikv/issues/15459)

主要现象：TiKV 启动失败，报错日志如下：

```
[2023/08/28 23:19:48.270 +00:00] [WARN] [config.rs:688] ["compaction guard is disabled due to region info provider not available"]
[2023/08/28 23:19:48.270 +00:00] [WARN] [config.rs:805] ["compaction guard is disabled due to region info provider not available"]
[2023/08/28 23:19:50.841 +00:00] [ERROR] [init_cluster.rs:309] ["error while open kvdb: Storage Engine Status { code: IoError, sub_code: None, sev: NoError, state: "Corruption: Blob file 3965 has been deleted twice" }"]
```

## Root Cause

Titan 优化去掉了写元数据文件时候的锁，这导致可能会有两个操作都需要删掉同一个文件，就并行地在元数据里面记录了两条删除。TiKV 重启的时候检查元数据的完整性的时候就挂掉了。

## Diagnostic Steps

1. 开启了 Titan : `rocksdb.titan.enabled = true`
2. 持续更新数据
3. `drop table`  或者 触发 region 调度
4. 重启 TiKV 失败

## Affected Versions

v6.5.4

## Resolution

修复版本 v6.5.5

## Workaround

None