Anyone had luck with high throughput IPC to GNU Radio?

GNU Radio
1

Hi all,

Has anyone had any luck achieving high throughput (e.g., supporting
interpolation of 8 or 16 with USRP2) from Octave to a GNU Radio
flowgraph?
I am trying to stream a signal to my GR flowgraph, and at first I tried
sockets but then realized it was way too slow, and so I moved to pipes
but I
am also finding it cannot keep up.

I have tried writing/reading in larger blocks, such as using an fwrite()
in
Octave of size 20480, and then attempting a larger read within GNU Radio
using a gr.file_source(20480,’/tmp/mypipe’) and then converting it to a
stream for the USRP2 with
gr.vector_to_stream(gr.sizeof_gr_complex,20480).
But alas, still no luck… I am under-running like crazy from the looks
of
my spectrum.

Has anyone had any better luck?

Thanks!
George

2

On Fri, Jul 30, 2010 at 8:38 AM, Kunal K.
[email protected]wrote:

Hi,

I am unfamiliar with Octave, so I cannot be sure about your particular
scenario, but a potential problem could be internal buffering between
writes… Maybe try flushing the stream more?

I could be wrong, but I thought named pipes stay in memory? It seems
like
part of my problem might be that pipe size is limited to something like
4k
in size, which does not allow me to push a lot of data through. It
seems
like I could modify this in linux/limits.h to increase its size.

3

Hi,

I am unfamiliar with Octave, so I cannot be sure about your particular
scenario, but a potential problem could be internal buffering between
writes… Maybe try flushing the stream more?

Kunal