Re: [Discuss-gnuradio] Mysterious rapid-capture bug

[Toby Oliver]

John Bratteli wrote:
> I brought this up some time ago, but no one was able
> to help me.  I have a little more information now, so
> maybe we can make progress.  
>
> In the application we are working on, we would like to
> perform continuous split-second captures from the USRP
> over days at a time.  Unfortunately, it hangs after an
> indeterminate amount of time.  The power of the
> computer running the program seems to have some
> bearing on the time before crash, but it is still
> pretty random.  We have run times from 2min to 23hrs. 
>   
I had a similar problem and it was really nasty to figure out, as far as
I remember it turns out it was due to memory fragmentation in the Kernel
USB buffer causing the USB bus to be starved of data. I think it was
Johnathan and Eric that tracked it down so they might have more
information.

Possibly more importantly the fix was to change the usrp.source to
include fusb_block_size=4096 and fusb_nblock=16.

Hope that helps.
Toby