Re: Flink SQL:Too few memory segments provided. Hash Join needs at least 33 memory segments.

Fri, 20 Mar 2020 01:53:25 -0700 

Hi,

- 看堆栈你是用了老的planner，推荐使用blink planner.
- 如果要在老planner上解决问题，提高Taskmanager的manage内存试试。

Best,
Jingsong Lee

On Fri, Mar 20, 2020 at 4:41 PM 烟虫李彦卓 <[email protected]> wrote:

> Hi, All:
>
> &nbsp;&nbsp;&nbsp;&nbsp;我在使用Flink1.10.0的SQL时，遇到了一个问题：
>
>
> Caused by: java.lang.IllegalArgumentException: Too few memory segments
> provided. Hash Join needs at least 33 memory segments.
>
>  at
> org.apache.flink.runtime.operators.hash.MutableHashTable.<init&gt;(MutableHashTable.java:401)
>
>  at
> org.apache.flink.runtime.operators.hash.MutableHashTable.<init&gt;(MutableHashTable.java:387)
>
>  at
> org.apache.flink.runtime.operators.hash.HashJoinIteratorBase.getHashJoin(HashJoinIteratorBase.java:51)
>
>  at
> org.apache.flink.runtime.operators.hash.NonReusingBuildSecondHashJoinIterator.<init&gt;(NonReusingBuildSecondHashJoinIterator.java:89)
>
>  at
> org.apache.flink.runtime.operators.JoinDriver.prepare(JoinDriver.java:194)
>
>  at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:474)
>
>  ... 4 common frames omitted
>
> 整个项目的逻辑是使用JDBCInputFormat从MySQL读数据，然后使用Flink
> SQL做聚合计算，再通过JDBCOutputFormat写入到MySQL。
>
> 其实代码在Flink1.7.2版本下是正常可用的，并已投入生产环境。但切换到Flink1.10.0后就出现这样的问题。通过排查，在聚合计算后，将每个聚合结果Table连接成一个Table时出现上述错误。这一步涉及到30个Table,29个left
> join，且通过试验，当第10次left join时就会报错。
>
> 希望得到你的回复，非常感谢！Thanks！



-- 
Best, Jingsong Lee

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