Re: 怀疑源码中的一个方法是never reached code

[Jing Ge]

Hi,

友情提醒：开ticket以及以后在dev里讨论，记得用英语哈。

祝好
Jing


On Tue, Jun 14, 2022 at 3:23 PM Yun Tang  wrote:

> Hi，育锋
>
> 我觉得你的分析应该是没问题的。可以创建一个ticket来修复该问题。另外，关于代码实现的具体讨论，建议在dev邮件列表讨论。
>
> 祝好
> 唐云
> 
> From: 朱育锋 
> Sent: Tuesday, June 14, 2022 19:33
> To: user-zh@flink.apache.org 
> Subject: 怀疑源码中的一个方法是never reached code
>
> Hello Everyone
>
>
> 在阅读ProcessMemoryUtils类的代码时，我怀疑sanityCheckTotalProcessMemory方法[1]中的主体逻辑永远都不会执行：
>
> 1.
> 在deriveJvmMetaspaceAndOverheadFromTotalFlinkMemory方法中，判断了是否显式配置了TotalProcessMemory[2]
> 2.
> false分支（也就是没有显式配置TotalProcessMemory）的逻辑中调用了sanityCheckTotalProcessMemory方法，而sanityCheckTotalProcessMemory方法的主体逻辑
>
> 只有在显式配置了TotalProcessMemory时[3]才会执行，所以sanityCheckTotalProcessMemory方法的主体逻辑应该永远不会执行
>
>
> 参照TaskExecutorFlinkMemoryUtils类中的sanityCheckTotalFlinkMemory方法（该方法与sanityCheckTotalProcessMemory方法逻辑类似，都是比较衍生的内存大小与显式配置的内存大小是否一致）的调用位置[4][5]，
>
> 我猜测sanityCheckTotalProcessMemory方法是不是应该放在deriveJvmMetaspaceAndOverheadFromTotalFlinkMemory方法中if分支的后面，而不是在分支里面
>
> 也有可能是对这段代码的理解不够，没有揣测到这么写的意图，希望大佬们帮忙确认下
>
> [1]
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L239
> <
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L239
> >
> [2]
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L170
> <
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L170
> >
> [3]
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L247
> <
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L247
> >
> [4]
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L101
> <
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L101
> >
> [5]
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L192
> <
> https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L192
> >
>
> Best regards
> YuFeng
>

Re: 怀疑源码中的一个方法是never reached code

[Yun Tang]

Hi，育锋

我觉得你的分析应该是没问题的。可以创建一个ticket来修复该问题。另外，关于代码实现的具体讨论，建议在dev邮件列表讨论。

祝好
唐云

From: 朱育锋 
Sent: Tuesday, June 14, 2022 19:33
To: user-zh@flink.apache.org 
Subject: 怀疑源码中的一个方法是never reached code

Hello Everyone

在阅读ProcessMemoryUtils类的代码时，我怀疑sanityCheckTotalProcessMemory方法[1]中的主体逻辑永远都不会执行：

1. 
在deriveJvmMetaspaceAndOverheadFromTotalFlinkMemory方法中，判断了是否显式配置了TotalProcessMemory[2]
2. 
false分支（也就是没有显式配置TotalProcessMemory）的逻辑中调用了sanityCheckTotalProcessMemory方法，而sanityCheckTotalProcessMemory方法的主体逻辑
只有在显式配置了TotalProcessMemory时[3]才会执行，所以sanityCheckTotalProcessMemory方法的主体逻辑应该永远不会执行

参照TaskExecutorFlinkMemoryUtils类中的sanityCheckTotalFlinkMemory方法（该方法与sanityCheckTotalProcessMemory方法逻辑类似，都是比较衍生的内存大小与显式配置的内存大小是否一致）的调用位置[4][5]，
我猜测sanityCheckTotalProcessMemory方法是不是应该放在deriveJvmMetaspaceAndOverheadFromTotalFlinkMemory方法中if分支的后面，而不是在分支里面

也有可能是对这段代码的理解不够，没有揣测到这么写的意图，希望大佬们帮忙确认下

[1] 
https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L239
 

[2] 
https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L170
 

[3] 
https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/ProcessMemoryUtils.java#L247
 

[4] 
https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L101
 

[5] 
https://github.com/apache/flink/blob/master/flink-runtime/src/main/java/org/apache/flink/runtime/util/config/memory/taskmanager/TaskExecutorFlinkMemoryUtils.java#L192
 


Best regards
YuFeng