# Anyone had luck with high throughput IPC to GNU Radio?

**URL:** <https://www.ruby-forum.com/t/anyone-had-luck-with-high-throughput-ipc-to-gnu-radio/192459>\
**Category:** GNU Radio\
**Created:** [July 30, 2010, 5:11pm UTC](https://www.ruby-forum.com/t/anyone-had-luck-with-high-throughput-ipc-to-gnu-radio/192459 "2010-07-30T17:11:52Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![george\_n](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@george\_n](https://www.ruby-forum.com/u/george_n)\
**Post date:** [July 30, 2010, 5:11pm UTC](https://www.ruby-forum.com/t/anyone-had-luck-with-high-throughput-ipc-to-gnu-radio/192459/1 "2010-07-30T17:11:52Z")

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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

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**Author:** ![george\_n](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@george\_n](https://www.ruby-forum.com/u/george_n)\
**Post date:** [July 31, 2010, 12:06am UTC](https://www.ruby-forum.com/t/anyone-had-luck-with-high-throughput-ipc-to-gnu-radio/192459/2 "2010-07-31T00:06:23Z")

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On Fri, Jul 30, 2010 at 8:38 AM, Kunal K.  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)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.

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**Author:** ![george\_n](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@george\_n](https://www.ruby-forum.com/u/george_n)\
**Post date:** [July 30, 2010, 5:39pm UTC](https://www.ruby-forum.com/t/anyone-had-luck-with-high-throughput-ipc-to-gnu-radio/192459/3 "2010-07-30T17:39:58Z")

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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