Issues with Parameter Configuration Effectiveness

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

Original topic: 参数配置生效问题

| username: TiDBer_1111

[TiDB Usage Environment] Production Environment
[TiDB Version] v4.0.10
[Encountered Problem]
Problem Description: When expanding drainer with tiup, the parameter was not closed. Later, the drainer.toml was modified and took effect after restarting. After a period of time, drainer restarted, and it seems that the [sync ddl] parameter became the default again?

Dear experts, can it only take effect permanently after modifying the metadata? Additionally, are there any recommended documents related to large table DDL?

| username: xfworld | Original post link

DDL for large tables in 4.x… seems like there’s no feature support, just a bunch of pitfalls… :rofl:

There are actually several ways to modify configurations, for example:

  • File configuration
  • In-memory configuration
  • Global in-memory configuration
  • Automatic loading configuration with tiup

Each corresponds to different scenarios and parameters…

As for the configuration of driner.toml, there are two ways to modify it:

  1. Through tiup edit-config, by overriding parameters to replace the default values
  2. By adjusting the configuration information in the local deploy directory’s toml to ensure successful loading, which is quite troublesome…
  3. Or by specifying a configuration file to make the configuration effective…

You can refer to this:

| username: TiDBer_1111 | Original post link

Thank you, boss~

| username: 呢莫不爱吃鱼 | Original post link

Learned.

| username: TiDBer_JUi6UvZm | Original post link

:+1:

| username: 舞动梦灵 | Original post link

I also have version 4.0x here. It was upgraded from 2.0, and it’s very bad. I’m afraid to modify any parameters. It feels safe only if it’s upgraded to at least 6.5 or above.

| username: 不想干活 | Original post link

Old versions can be worrisome; it’s best to upgrade.