Can multiple replicas of the same region exist on a single TiKV node?

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This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: 一个TiKV节点上是否可以存在同一个region的多个副本

| username: alfred

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| username: 啦啦啦啦啦 | Original post link

No, when PD schedules, it will not store multiple replicas of a region in the same TiKV, as this would be meaningless.

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| username: 特雷西-迈克-格雷迪 | Original post link

If the number of region replicas is greater than the number of nodes, it might be possible; if the number of replicas is less than the number of nodes, it should not be possible.

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| username: wuxiangdong | Original post link

With this placement rule in version 6.2, you can specify the number of replicas and place multiple replicas on a specific label.

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| username: alfred | Original post link

Yes, I saw this feature, although placing multiple replicas on a single TiKV node is meaningless.

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| username: h5n1 | Original post link

TiDB strictly ensures that there is only one replica within one TiKV. Please note the distinction between TiKV and host.

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| username: xiaohetao | Original post link

Under normal PD scheduling, a region’s replicas will not be placed on the same TiKV instance, but they may be placed on another TiKV instance on the same host.