Is the destination a topic or a queue? If it's a topic, have you considered using retroactive consumers with a timed subscription recovery policy [2] set to 6 minutes?
[1] http://activemq.apache.org/retroactive-consumer.html [2] http://activemq.apache.org/subscription-recovery-policy.html Regards, *Raúl Kripalani* *Principal Consultant | FuseSource Corp. r...@fusesource.com | fusesource.com <http://www.fusesource.com/> skype: raul.fuse | twitter: @raulvk <http://twitter.com/raulvk>, @fusenews<http://twitter.com/fusenews> * blog: F3 - Flashes From the Field<http://blog.raulkr.net/?utm_source=fusesourceemail&utm_medium=email&utm_campaign=fusesourcemail> | aboutme: http://about.me/raulkripalani <http://twitter.com/fusenews> On 7 August 2012 13:47, fenbers <mark.fenb...@noaa.gov> wrote: > I've configured my ActiveMQ client not to acknowledge messages. This is > because I want the messages redelivered if the user stops and restarts the > client app. The messages expire in 6 minutes anyway. So any older > messages > *shouldn't* be delivered. > > I notice in my $ACTIVEMQ_HOME/data/kahadb directory there are files named > db-N.log where N is a sequential number starting at 1, and these are all 33 > Megabytes in size. When N gets to 300+, we see a huge performance hit in > the apps that use the broker – even though we still have plenty of free > disk > space. The only way I've found to rectify the performance problem is to > delete the contents of the kahadb directory and restart ActiveMQ. This > fixes the problem temporarily until the log files increase to over 300 > again. > > When N > 300, the modification times of lower-numbered files are > significantly older. If the messages expire after 6 minutes, what purpose > do these older db-N.log files serve? What can I do to prevent the > performance degradation as these db-N.log files build up? What can I do to > prevent these files from accumulating in the first place? > > This article: > > http://activemq.apache.org/why-do-kahadb-log-files-remain-after-cleanup.html > suggests the problem occurs because there are un-acknowledged messages > causing the files to still be “in-use”. So I could probably eliminate the > *.log file accumulation by acknowledging the messages, but I cause another > problem in doing so, in which messages will not be not redelivered if the > client is restarted. For the purposes described in my first paragraph, the > messages are deliberately not acknowledged. Can I acknowledge messages and > yet still have the unexpired messages redelivered if my client app is > restarted? Or can I safely delete the log files that are significantly > older than 6 minutes? > > Mark > > > > -- > View this message in context: > http://activemq.2283324.n4.nabble.com/db-N-log-files-accumulating-tp4654843.html > Sent from the ActiveMQ - User mailing list archive at Nabble.com. >
