Fix mistranslation in titan-overview.md (#12257) (#12300)

storage-engine/titan-overview.md

@@ -29,7 +29,7 @@ The prerequisites for enabling Titan are as follows:
 
 - The average size of values is large, or the size of all large values accounts for much of the total value size. Currently, the size of a value greater than 1 KB is considered as a large value. In some situations, this number (1 KB) can be 512 B. Note that a single value written to TiKV cannot exceed 8 MB due to the limitation of the TiKV Raft layer. You can adjust the [`raft-entry-max-size`](/tikv-configuration-file.md#raft-entry-max-size) configuration value to relax the limit.
 - No range query will be performed or you do not need a high performance of range query. Because the data stored in Titan is not well-ordered, its performance of range query is poorer than that of RocksDB, especially for the query of a large range. According PingCAP's internal test, Titan's range query performance is 40% to a few times lower than that of RocksDB.
-- Sufficient disk space (consider reserving a space twice of the RocksDB memory consumption with the same data volume). This is because Titan reduces write amplification at the cost of disk space. In addition, Titan compresses values one by one, and its compression rate is lower than that of RocksDB. RocksDB compresses blocks one by one. Therefore, Titan consumes more storage space than RocksDB, which is expected and normal. In some situations, Titan's storage consumption can be twice that of RocksDB.
+- Sufficient disk space (consider reserving a space twice of the RocksDB disk consumption with the same data volume). This is because Titan reduces write amplification at the cost of disk space. In addition, Titan compresses values one by one, and its compression rate is lower than that of RocksDB. RocksDB compresses blocks one by one. Therefore, Titan consumes more storage space than RocksDB, which is expected and normal. In some situations, Titan's storage consumption can be twice that of RocksDB.
 
 If you want to improve the performance of Titan, see the blog post [Titan: A RocksDB Plugin to Reduce Write Amplification](https://pingcap.com/blog/titan-storage-engine-design-and-implementation/).