config配置支持：min-slaves-to-write/min-slaves-max-lag

[yili1991]

Which PikiwiDB functionalities are relevant/related to the feature request?

No response

Description

v3.5.5支持一下config，减少哨兵模式下主从切换导致的数据丢失情况。

• min-slaves-to-write
• min-slaves-max-lag

Proposed solution

• min-slaves-to-write
• min-slaves-max-lag

Alternatives considered

• min-slaves-to-write
• min-slaves-max-lag

[chejinge]

主从切换的时候可能会数据丢失或者主从不一致

[Issues-translate-bot]

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Data may be lost or master-slave inconsistency may occur when switching between master and slave.

[Mixficsol]

后续看一下参数作用

[Issues-translate-bot]

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Let’s take a look at the parameters later

[cheniujh]

这一块考虑了一下，暂时认为在控制面加这个逻辑比较合适，具体做法可以是：
当发现某个从节点lag超过阈值，向该节点发送config set slave-priority 0，这样redis-sentinel就不会再failover的时候将他列为候选人。相应的，当该滞后节点的进度追上时，再执行config set slave-priority 100，让其重新获得候选资格。

[Issues-translate-bot]

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After thinking about this for a while, I temporarily think it is more appropriate to add this logic to the control surface. The specific method can be:
When it is found that a slave node lag exceeds the threshold, send config set slave-priority 0 to the node, so that redis-sentinel will not list him as a candidate in failover. Correspondingly, when the progress of the lagging node catches up, execute config set slave-priority 100 to allow it to regain candidacy.