The configuration for number of query errors in the `show queries` does not work anymore · confluentinc/ksql#9533

(3 留言) (0 反應) (1 負責人)Java (5,739 star) (1,048 fork)batch import

P1buggood first issuestreaming-engine

描述

Describe the bug When a query has errors, a list of errors collected is displayed by the SHOW QUERIES EXTENDED or EXPLAIN <query> commands. This list has a config to limit the number of errors displayed. The config is ksql.query.error.max.queue.size and is default to 10. However, the SHOW QUERIES command is displaying more errors than what it is configured and it keeps growing.

Looking at the code, I found the issue was caused by this fix https://github.com/confluentinc/ksql/pull/8875

The queue used to use an EvictionQueue class which evicts queue elements when a size/capacity has been reached. After the previous fix, the capacity is not used anymore, so the queue becomes unbounded on size. It is still time-bounded because the evict() method is called after adding an element. This evict method removes elements that expired in 1 hour window (configured).

Fix: We should keep the queue bounded to capacity and time (as configured). It is important to keep the queue thread-safe, so maybe the fix should be in the evict() method to remove elements if the queue has reach the configured capacity.

貢獻者指南

技術棧: java
領域: backenddata
議題類型: bug
難度: 3
預計時間: 1-3 hours
活動狀態: stale
清晰度: clear
前置要求: Java programmingUnderstanding of queue data structures
新手友善度: 60
研究方向: Examine the current implementation of the EvictionQueue class and its evict() method. Review the changes introduced in PR #8875 to understand why the capacity limit was removed. The fix should ensure the queue remains bounded both by capacity (ksql.query.error.max.queue.size) and time (1 hour window). Pay attention to thread safety requirements.