Some TiFlash operators in EXPLAIN ANALYZE don't have runtime stats
Open
component/tiflash
sig/execution
type/enhancement
- Dominant language
- Go
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Description
## Enhancement
When execution `EXPLAIN ANALYZE ...`, we can get an execution plan with runtime stats such as `actRows` and `execution info`. If there is a Limit operator on root, some operators on TiFlash miss their runtime stats(`actRows:0, tiflash_task:{time:0s, loops:0, threads:0}`). Runtime stats of TiFlash operators are sent to TiDB by last block. When the Limit operator terminates the execution of TiFlash early, TiDB cannot receive runtime stats of TiFlash operators. Fixing the problem can help us diagnose slow queries.
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