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Nifi Cannot swap in FlowFiles from location

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New Contributor
107641-nifiqueueswapthreshold.png


107651-swap.png


When 43,508 flow files are sent to SplitJson, they are stacked in the queue and processed within the value set in nifi.queue.swap.threshold(= 20000).

After that, a swap file was created and there are 23,508 stacks in the queue

but it is not running any more and is stopped.


nifi-app.log seems to be in progress because of an error in swap in.

2019-04-05 16:31:59,534 WARN [Timer-Driven Process Thread-6] o.a.n.controller.FileSystemSwapManager Cannot swap in FlowFiles from location D:\download\NIFI-1~1.0-B\NIFI-1~1.0\.\flowfile_repository\swap\1554449490032-01691059-3464-1fc9-0a1a-9def8b12c89e-15293fe8-c2ea-4f9d-a4fb-fd992716903d.swap because the FlowFile Repository does not know about this Swap Location. This file should be manually removed. This typically occurs when a Swap File is written but the FlowFile Repository is not updated yet to reflect this. This is generally not a cause for concern, but may be indicative of a failure to update the FlowFile Repository.


Changing nifi.queue.swap.threshold = 40,000 will process up to 40,000 and stop equally.



Thank you for your help.

5 REPLIES 5

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Contributor

We have the same issue, has anyone found any solution to this case?

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New Contributor

This seems to happen since 1.9, I reverted back to 1.8.0 and it runs again.

Before I did this, I turned off the caching for any repo in the nifi.properties. Had no effect on this issue, only made Nifi extremely slow (as expected)

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New Contributor

Breakdown down your problem into layers.after splitjson try ingesting into Kafka/HDFS then you understand why its not swapping.


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Contributor

After read the content of the link below a made some changes in both nifi.properties e boostrap.conf files. That changes solved the issue, for now.

https://community.hortonworks.com/articles/7882/hdfnifi-best-practices-for-setting-up-a-high-perfo.h...


nifi.properties file:

<nifi.queue.swap.threshold=100000/>


Bootstrap.conf file:

<# JVM memory settings

java.arg.2=-Xms4g

java.arg.3=-Xmx4g/>


coment Garbage collector usage

<# java.arg.13=-XX:+UseG1GC/>


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Super Mentor

@dhhan74 

 

The attached screenshot shows your running version as Apache NiFi 1.9.0.
There is a known issue in that released that results in the ERROR condition you have encountered:

https://issues.apache.org/jira/browse/NIFI-6285

 

This issue was addressed as of Apache NiFi 1.10.

 

Hope this helps,

Matt