OOM even when using paging

[takeshi10]

Hello everybody i just have a quick question:

We have a hornetq server running here (not clustered) and we deliver something around 250 messages per second.

Over the weekend, the consumers had stopped (for some external reason) on our test server and sunday, hornetQ stopped with an OOM: Heap Space even though we use PAGE as our address full policy. Now, the application (witch embedds hornetq) will not even start (throwing OOM) unless i clean the paging directories. At the moment, the heap is dominated (80%) by instances of PageSubscriptionImpl and JournalImpl

The settings looks as follows:

-max size bytes is 20k

-page size bytes is 10k

-ack batch size is 1k

-4 queues and 1 topic (which doesnt have any durable subscriber)

Im sure i'm doing something wrong so can anybody help me out?

Thanks in advance

edit:

I forgot to mention that im using hornetq 2.2.21.Final. The application is running with 1gb of maximum heap and nothing else is using significant amounts of memory.

[clebert.suconic]

If you are using transactions, the system will also need to add the page-transaction into memory, so you still can get out of memory on that case.

[takeshi10]

Oh right well im not using transaction either. I wonder why is hornet trying to load all pages into memory at all.

[takeshi10]

Ok so i managed to get it to come up again by decreasing the number of consumers (to 1 for each queue). I was using 4 for each queue. Could that be the problem? How do i properly size the memory requirements? In other words, how do i know how much memory i need, given Q queues, C consumers, M max size and J journal size?

[clebert.suconic]

What's probably happening then is that you have a large consumer-window size for each consuemr, and that's depaging a lot of stuff?

It's hard to tell.. this is all about sizing on each consumer.