Re: [Discuss-gnuradio] Good laptop for GR/USRP

[Greg Troxel]

It would be good to see benchmarks of the blocks that dominate
receivers on various processors.  I think for our 802.11 receiver the
most time went to FIR filters.

You didn't specify if your workload was floating point or integer; I
suspect that the chip with best performance will be different.


  3) Memory probably isn't a huge concern. We will probably be getting 1GB
  of ram.

Maybe that's enough, but I wouldn't buy a machine with < 2 GB for any
purpose today.

You didn't mention the USRP bandwidth you want, but I'll guess that
you'll be maxed out at 32 MB/s.  Intel EHCI chips work well, and I
have the impression that many other implementations do not.

Perhaps obvious, but hardware reliability and having the devices
supported by the OS you are going to run, without binary drivers, is
also in general important.

I am using a Thinkpad T60 with Core Duo T2300:
cpu0: Intel Pentium M (Yonah) (686-class), 2161.46 MHz, id 0x6e8
cpu0: "Genuine Intel(R) CPU           T2600  @ 2.16GHz"
cpu0: I-cache 32 KB 64B/line 8-way, D-cache 32 KB 64B/line 8-way
cpu0: L2 cache 2 MB 64B/line 8-way
cpu0: using thermal monitor 1

There is L2 cache, but I don't have that handy. 


Now you can get T60s with Core 2 Duos.

With the 100 GB disk that came with the T60, I get 39 MB/s raw
read rate (at the beginning), and I think write is similar.   I have
more RAM than free disk space so can't benchmark writing reasonably.

An external disk may well be faster, but typically you'd use USB and
I'm not sure the controller can deal with that at the same time as the
USRP and max them both out.  You might consider some sort of
network-attached storage - I'm unclear on your portability/cost
requirements.

What data rate do you need to sustain?

Eric has an X60 that he's been happy with.

If you're going to run GNU Radio semi-constantly on laptops, I bet
you're going to have grief from too much heat.  If so, get a 3-yr
warranty (e.g. Thinkpad) and install them with risers for good
airflow.  The T60 is a lot better in this regard than the T30 I had
before, which ran very hot, and in which the video card failed after
3.5 years (of very hard and frequent use, so I was happy overall).