Details on changing singleusrp buffer allocations

Could anybody please tell me how to set the following parameters? I am
working on supporting UHD in the Python digital communication example
and hopefully I can soon share my code with the list.

* *recv_frame_size:* The size of a single receive buffer in bytes
* *num_recv_frames:* The number of receive buffers to allocate
* *send_frame_size:* The size of a single send buffer in bytes
* *num_send_frames:* The number of send buffers to allocate
* *concurrency_hint:* The number of threads to run the IO service

Andrew

Pass them in with the device arguments, just like addr, serial and the
rest. Its just more optional key/value string pairs

device_address[“recv_frame_size”] = “1024”

-josh

Josh,

Thanks very much.

When I use UHD transmitting packets, after each packet, there is a “U”
printed out. Would you tell me what “U” means?

In early GNU Radio versions, “U” means CPU underrun–GNU Radio not
sending data fast enough to a sink, either a USRP or an audio. But UHD
uses UDP packets, so I cannot correlate “U” with CPU underrun.

Andrew