TiKV Write Stall

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

Original topic: tikv write stall

| username: Raymond

May I ask, when the number of Immutable MemTables in RocksDB reaches a certain threshold, it triggers a write stall. However, are there specific parameters to control this? For example, when the number of Immutable MemTables reaches a certain threshold, it triggers a write stall slowdown, and when it reaches another threshold, it triggers a write stall stop. Similar to how when the number of files in level 0 of RocksDB reaches the value set by level0-slowdown-writes-trigger, it triggers a slowdown write stall, and when it reaches the value set by level0-stop-writes-trigger, it triggers a stop write stall. Are there corresponding parameters to control the write stall for Immutable MemTables?

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

It seems that there can be at most 5 Immutable MemTables.

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| username: alfred | Original post link

When disk IO reaches its bottleneck, it will trigger a write stall. It seems there are no parameters to control this at the TiDB level.

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| username: TiDBer_jYQINSnf | Original post link

You can change the number of memtables in the TiKV configuration.

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| username: h5n1 | Original post link

When there are no parameters and fixed rules, increase max-write-buffer in such cases.