docs: add how-to guides for TiDB session variable tuning#16
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terry1purcell wants to merge 1 commit intopingcap:mainfrom
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docs: add how-to guides for TiDB session variable tuning#16terry1purcell wants to merge 1 commit intopingcap:mainfrom
terry1purcell wants to merge 1 commit intopingcap:mainfrom
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Add 7 scenario-based how-to guides covering all non-cost-factor session variables, grouped by tuning concern: query execution, cost model, statistics collection, stats loading, memory/resources, TiFlash/MPP, and plan baselines. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
winoros
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Mar 16, 2026
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We need a guide to tell it when to read the how-to directly.
fixdb
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Mar 16, 2026
| SET GLOBAL tidb_enable_historical_stats = OFF; | ||
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| **Benefit:** Stops TiDB from storing historical stats snapshots, reducing memory pressure. Only enable this if you have a specific operational need to compare stats across time periods. |
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We turned it off by default because the implementation still has bugs, causing a lot of issues
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You're right. I need to go through again and validate which ones we are actually planning to deprecate.
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/hold |
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Add 7 scenario-based how-to guides covering all non-cost-factor session variables, grouped by tuning concern: query execution, cost model, statistics collection, stats loading, memory/resources, TiFlash/MPP, and plan baselines.