LimeSDR streaming buffers

Hi all,

In a quest to reduce latency for an application, I want to try and minimise all of the buffers/packet sizes possible. I’m using GNU Radio, with the path LimeSuite -> SoapyLMS7 -> SoapySDR -> gr-Osmosdr -> GNU Radio.

So far, I’ve forced the config.performanceLatency parameter to zero in setupStream in streaming.cpp of the SoapyLMS7 code, which helped significantly. I also tried forcing config.bufferLength to various values, but seemingly with no effect.

I’ve found it a little tricky to drill through the code and locate any other potential buffers/packet sizes to be reduced; would anyone with a better knowledge of the LimeSDR streaming code be able to help? I am aware that there is an FPGA packet size of 1020 samples which will require editing the FPGA gateware to reduce, but I just wanted to check if there were any other buffers /anything else that would affect latency which I could try? By my calculations, the FPGA packet size is not sufficient to be responsible for quite all of the latency I am seeing.

Thanks and regards,


Hello DasSidG, did you ever find a good way to cut down the buffer sizes?