Publishers & Subscribers : queue_size, blocking, synchronous/asynchronous
I've been working with ROS for quite a long time and now I feel that I am somewhere between the valley of despair and sole of enlightenment portions of the Dunning-Kruger effect curve.
I have some basic doubts about publishers, subscribers, and their internal working.
1) Can someone give a brief overview of the low-level working of publishers and subscribers? I want to know how to messages flow through queues, buffers, etc., and the serialization process. What exactly do all these terms mean?
2) I know what do the terms synchronous and asynchronous mean, but I want to know them in the terms of publishers and subscribers. Are publishers and subscribers sync/async or are their callback functions and publish() methods syn/async?
3) I want to understand the queue_size parameter in detail. I'm more bothered to know what exactly it is rather than what should be a good way to choose its value.
I would be really thankful to the community to help me and others understand these basic concepts via this post.
Thanks!
Why did you post a duplicate and why did you delete #q396293?
@gvdhoom I deleted it because I posted the same question again by mistake. It's draft had been lying around in text case to ask question.