Re: [Discuss-gnuradio] UHD host resources and system suggestions

[Marc Epard]

On Sep 3, 2010, at 5:57 PM, Marcus D. Leech wrote:

> I'll comment that a 1.6GHz machine that's getting close to 4 years old
> isn't particularly "beefy" by todays standards.  Certainly not
>  beefy enough to sustain two 25Msps threads without "problems".

Thanks, Marcus. That was helpful and as I suspected. So over the weekend I 
built* a new system that should eliminate the speed concern (for now ;-). It's 
an Intel Core i7-980x with 6GB of the "world's fastest" XMP-certified RAM. 
64-bit Ubuntu screams on it. Running make with --jobs=8 builds gnu-radio and 
Ettus UHD rather quickly. My UHD app is running much better and the GUI is 
actually usable while I'm doing a transmit+receive run. 

However, the transmit side is still troublesome. Periodically, a burst of Us 
comes out of the UART and there are always a lot of 
EVENT_CODE_SEQ_ERROR_IN_BURST events -- like several thousands per second. I've 
tried this on two different ethernet NICs identified by Ubuntu as an Intel 
82567V-2 (on the motherboard) and a Realtek RTL8111/8166B (in a PCIe slot). I 
have the transmit and receive buffers set to 500,000,000.

I'm digging into the host and USRP2 source to figure out where 
EVENT_CODE_SEQ_ERROR_IN_BURST come from and how transmit flow control works. 

Any pointers would be appreciated.

-Marc

* It's the first time I've built a system as I normally leave that to Apple. It 
was fun.