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https://issues.apache.org/jira/browse/NIFI-5024?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16474031#comment-16474031
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ASF GitHub Bot commented on NIFI-5024:
--------------------------------------

Github user nsanglar commented on the issue:

    https://github.com/apache/nifi/pull/2594
  
    @MikeThomsen The AppVeyor build failed because:
    ```Build execution time has reached the maximum allowed time for your plan 
(90 minutes).```
    Is it a common issue?


> Deadlock in ExecuteStreamCommand processor
> ------------------------------------------
>
>                 Key: NIFI-5024
>                 URL: https://issues.apache.org/jira/browse/NIFI-5024
>             Project: Apache NiFi
>          Issue Type: Bug
>    Affects Versions: 1.3.0
>            Reporter: Nicolas Sanglard
>            Priority: Minor
>         Attachments: Screen Shot 2018-03-28 at 15.34.36.png, Screen Shot 
> 2018-03-28 at 15.36.02.png
>
>
> Whenever a process is producing too much output on stderr, the current 
> implementation will run into a deadlock between the JVM and the unix process 
> started by the ExecuteStreamCommand.
> This is a known issue that is fully described here: 
> [http://java-monitor.com/forum/showthread.php?t=4067]
> In short:
>  * If the process produces too much stderr that is not consumed by 
> ExecuteStreamCommand, it will block until data is read.
>  * The current processor implementation is reading from stderr only after 
> having called process.waitFor()
>  * Thus, the two processes are waiting for each other and fall into a deadlock
>  
>  
> The following setup will lead to a deadlock:
>  
> A jar containing the following Main application:
> {code:java}
> object Main extends App {
>   import scala.collection.JavaConverters._
>   val str = 
> Source.fromInputStream(this.getClass.getResourceAsStream("/1mb.txt")).mkString
>   System.err.println(str)
> }
> {code}
> The following NiFi Flow:
>  
> !Screen Shot 2018-03-28 at 15.34.36.png!
>  
> Configuration for ExecuteStreamCommand:
>  
> !Screen Shot 2018-03-28 at 15.36.02.png!
>  
> The script is simply containing a call to the jar: 
> {code:java}
> java -jar stderr.jar
> {code}
>  
> Once the processor calls the script, it appears as "processing" indefinitely 
> and can only be stopped by restarting NiFi.
>  
> I already have a running solution that I will publish as soon as possible.
>  



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