This page is a collection of FAQ and How to-s for Qpid. If you have a question, post it to the users list and we will place the answer here to build out our FAQ/ How to.

FAQ

How To

How to use RDMA with Qpid

The RDMA plugin uses native OFED1.3 and puts AMQP directly onto the DMA. When using the RDMA plug-in for Qpid note the following

• IP over IB or Fibre needs to be setup for the initial negociation
• You need to make sure you have enough memory to pin for DMA use ulimit -l something large
• you might need to edit /etc/security/limits.conf first then log in again

Once you have it up and running, use latencytest to make sure it is working. You should see latencies between 50 and 80us round trip.

> The TTL can be set in the message headers and the messages get dequeued if TTL expires.

Message TTL, auto expire

I need to be able to set time for a message that I send to be removed from the queue if it is not read by my subscriber. For example: I enqueue a message and I want it to be automatically dequeued after a certain amount of time has passed.Is there a feature like this in qpid?

yes, the TTL can be set in the message headers and the messages get dequeued if TTL expires

E.g. from c++:

    Message m("Hello World!");
    m.getDeliveryProperties().setTtl(500);

Sets a 500 millisecond timeout.