# Tiflash Core Feature: Asynchronous Replication


![left](./student-guide/diagram/30-Asynchronous-replication-01-01.png)

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Raft synchronization, region
Do not vote in Raft
Does not affect TP

The following figure is an illustration of TiFlash participating in TiKV replication. First of all, we know that the region in TiFlash and TiKV's region data are the same, but the column store version is used.

Second, the region in TiFlash uses the learner role to access the original Raft Group of TiKV to form a new Raft Group. However, the region in TiFlash does not participate in voting or elect, and is not counted as a majority member. That is, if the Leader has written the follower of the majority, you can confirm that the data was written successfully, regardless of whether the learner node in TiFlash was written successfully. In this way, TiFlash is an asynchronous replication, which has very little impact on the performance of TiKV.

Finally, TiFlash internally uses a fast update mechanism based on the primary key, so that although it is an asynchronous replication, it does not have much delay with TiKV.