I'm new to the Yún. Does the latest OpenWRT YUN 1.5.3 image include real-time extensions, such as RTAI or Xenomai? From what I've ready, OpenWRT isn't real-time, but there are forks that add real-time extensions. I haven't been able to determine whether the Yún image includes any such extensions.
I have an application where I would like to put two Yún's alone on the same wifi network to chat with each other in near real-time. I need to characterize the worst-case response that I could expect when sending a message from one to the other. I know that real-time extensions could help.
The absolute response time isn't that important to me. What is more important is that once I know the response time, I could reasonably expect that time (plus a safety margin) to not be exceeded under normal circumstances.
The answer you are looking for is that the YunOS is based on OpenWRT, which is based on Linux.
Does Linux have any realtime extension? Yes.
Are these extension ported to OpenWRT? Some.
Do I have a list of them? No.
Is more information available? Yes
SonnyYu might have some information, but from what I know. It is best to ask these question at OpenWRT. Then you may need to recompile the kernel, or at the very lest install the extra module on your system.
ejubenville:
I'm new to the Yún. Does the latest OpenWRT YUN 1.5.3 image include real-time extensions, such as RTAI or Xenomai? From what I've ready, OpenWRT isn't real-time, but there are forks that add real-time extensions. I haven't been able to determine whether the Yún image includes any such extensions.
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Yún = ATmega32U4+ AR9331
ATmega32U4 is MCU, and it is hardware real-time extensions.
ejubenville:
...
I have an application where I would like to put two Yún's alone on the same wifi network to chat with each other in near real-time. I need to characterize the worst-case response that I could expect when sending a message from one to the other. I know that real-time extensions could help.
The absolute response time isn't that important to me. What is more important is that once I know the response time, I could reasonably expect that time (plus a safety margin) to not be exceeded under normal circumstances.
The WebSocket specification defines an API establishing "socket" connections between a client and a server. In plain words: There is an persistent connection between the client and the server and both parties can start sending data at any time. It is low latency (response time) and real time.