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I am trying to understand how ActiveMQ Artemis manages the journal files (under data/journal) and when it creates new ones. I read the documentation, but it wasn't clear how the files are create. I have a broker.xml has simple settings (won't be able to share unfortunately). Here are a few:

  • journal min threads - 2
  • journal pool size - 50
  • file size is defaulted to 10MB.

ActiveMQ Artemis starts, and I see 2 files are already created under /data/journal. I am now running a request that posts a lot of messages in a very short time. These messages are being actively consumed. I am publishing a lot of messages but they are not accumulating as fast because the consumer is consuming them. However, this doesn't cause the files to grow to recreate the space issue.

As the message volume is going up I don't see the number of files going up. It goes up and stays at 12 files for a long time. I can understand the message # is not sufficient trigger additional files if only the latest journal file is being written to. However, I see all the 11 files have updated timestamps making me think they are being rotated.

My paging directory is empty.

I am trying to understand why the journal is not growing despite the message volume.

Justin Bertram
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sg1973
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  • yes these messages are being actively consumed. I am trying to understand why the journal is not growing despite the message volume. Yes I read the documentation but it wasn't clear how the files are create. Thanks for prompt responses! – sg1973 Feb 02 '22 at 21:21
  • My paging directory is empty. – sg1973 Feb 03 '22 at 02:28
  • broker.xml has simple settings (won't be able to share unfortunately). Does this mean the journal will grow if there are more messages in memory? then how about i stop consuming the messages but continue to publish them? – sg1973 Feb 03 '22 at 02:48
  • You use the phrase "message volume" and talk about how it's going up. Are you referring to the number of messages you're sending per second or the number of messages that are accumulating on the broker? If you're consuming messages as quickly as you produce them then there should be no accumulation of messages on the broker which means the journal won't grow either. – Justin Bertram Feb 03 '22 at 03:01
  • Hi Justin, Yes. I am publishing a lot of messages but they are not accumulating as fast because the consumer is consuming them. I will try to see if i can stop the consumer and see what happens. – sg1973 Feb 03 '22 at 13:48

1 Answers1

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From what I can tell, message consumption has reached a break-even point with message production so that messages are not accumulating on the broker therefore the journal is not actually growing in size. The journal files are simply being re-used as messages are being added & acknowledged.

Justin Bertram
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