1 Reply Latest reply on Aug 20, 2010 12:42 AM by clebert.suconic

    Large number of paging files

    johnnysoccer

      We have a large number of topics (800) that can create a large number of small paging files. Seems like if we get to around 5000 paging files, HornetQ chokes, and we are not able to recover without removing the paging and journal directories.

       

      Is this a known issue?

      Is there an upper bound to the number of paging files a queue can have?

       

      A little more insight on the scenario...

       

      We have a main topic that all our clients connect to with a durable subscription. it is possible that any number of these clients could be slow, or disconnected for a period of time, and we don't want paging on the primary topic to prevent other clients from receiving messages.  To avoid this, we have set a message count threshold where we move messages for a specific client to their "offload" topic so that they can be picked up later.

       

      The offload topics have a much smaller memory and page file size setting so that we can try to accommodate up to 15% of the clients being unavailable.  In some scenarios, up to 4 of the topics (though we've seen it with just 1) will end up with over 5000 paging files, causing the crash.

        • 1. Re: Large number of paging files
          clebert.suconic

          You didn't provide much information... so it's hard to me to say anything. (I'm not really sure what choke would mean here.. an exception trace... logs would provide me more info).

           

           

          You should probably look at 2.1.2 as we fixed a few issues around journal, compacting and paging.

           

           

          One of the issues on paging was a JDK bug (as it was getting out of memory what would require a restart), that we've implemented a workaround.