Open polestar2012 opened 1 year ago
@Connor1996, would you please help confirm whether "There are 2 RocksDB instances in TiKV, a total of 4 CFs." is correct? Thanks.
Indeed, it should be 5 CFs: kvdb: defaultCF, writeCF, lockCF, raftCF raftdb: defaultCF
Though with raft-engine, raftdb does not exist anymore.
File: /release-6.5/storage-engine/rocksdb-overview.md
The data written to RocksDB is written to MemTable firstly. When the size of a MemTable exceeds 128 MB, it switches to a new MemTable. There are 2 RocksDB instances in TiKV, a total of 4 CFs. The size limit of a single MemTable for each CF is 128 MB. A maximum of 5 MemTables can exist at the same time; otherwise, the foreground writes is blocked. The memory occupied by this part is at most 2.5 GB (4 x 5 x 128 MB).