Updating the number of replicas is slow when replication.max-replicas is changed from 3 to 1

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

Original topic: replication.max-replicas从3设置为1副本数量更新慢

| username: TiDBer_FMWXa7ja

[TiDB Usage Environment] Production Environment / Test / Poc
[TiDB Version]
[Reproduction Path]
[Encountered Problem: Problem Phenomenon and Impact] By setting replication.max-replicas to 1 through set config pd, the number of replicas of the region was adjusted from 3 to 1. It has been 4 days, and the number of region replicas of the same table is sometimes 2 and sometimes 1. Why is the adjustment of region replicas so slow?
[Resource Configuration]
[Attachments: Screenshots/Logs/Monitoring]


| username: magic | Original post link

| username: TiDBer_FMWXa7ja | Original post link

Okay, thank you.

| username: Minorli-PingCAP | Original post link

You can adjust the scheduling parameters of PD, but single replica is highly discouraged.