Hi, i am using connext v. 6.0.0
I have large data with struct that you can see in sample that attached to this message.
I dont want to change sequences and strings to arrays.
I want to send samples periodically there for I dont want to change its qos to reliable.
It works correctly sometimes, as you can see in admin console if qos settings was compatible with your OS. But regularly it doesnt work currectly.
What is the best way to sending data with that limitations?
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I'm not sure what you mean by "works correctly sometimes" versus "doesn't work currently". What do you mean by "doesn't work"?
DDS must break up data packets > 64 KB into fragments and then reassemble the fragments into the original data sample. If a fragment is lost, then without using RELIABLE qos settings, the entire sample will be lost. If that's what you mean by "doesn't work", then there is no solution unless you use RELIABLE QoS settings that will force DDS to repair the lost fragment.
Sorry, there is no "magic". If the network loses fragments of a larger data packet, the entire data packet is lost unless the middleware is allowed to use a reliable protocol to repair the lost fragments.
Hi,
I think you should try to send large data periodically without changing sequences or strings to arrays and without using reliable QoS you may want to adjust the best effort QoS settings. Try lowering the send and receive buffer sizes to handle larger data more efficiently, and consider increasing the history depth to ensure your data is available for a longer period before being overwritten. Additionally, check your network configuration and the compatibility of your DDS (Data Distribution Service) settings with the operating system to ensure smooth data flow.
Thanks
Wow, the above sounds like it was AI generated.
It sounds like it's giving good advice, but the actual advice that it gives is entirely wrong. When sending large data that needs to be set in fragments, you absolutely need to use RELIABLE QoS and adjust the reliability protocol settings to accommodate your situation. There are really no settings for BEST EFFORT that change how DDS sends data...other than setting Reliability to BEST_EFFORT.
"lowering the send and receive buffer sizes to handle large data more efficiently"...what a load of crap. That's totally the opposite of what you need to do.
Please ignore the post above...and search community.rti.com for "large data" and you'll get a bunch of posts as well as examples of how to do that properly with Connext DDS.