[Discuss-gnuradio] How to balance workload among cores? Laptop cannot keep up with the USRP2 data flow.

Hi all!

I am Tx/Rx a FM signal at the same time, but I can see a lot of SSSSS messages that mean my CPU cannot keep up with all frames generated by the USRP2 and drop most of them.
However I have a quite new laptop with a CPU:Intel(R) Core(TM) i5 CPU       M 520  @ 2.40GHz  on Ubuntu 10.4

I guess that my laptop is enough to run my FM Tx/Rx and I wonder if I can balance the workload among all my four cores to see if my application improves (ethernet interface doens't drop any frame).

Looking at other post of the mailing list I found:

1)"Try using numactl".
Well, for me is not possible, after installing that library and running:
:~$ numactl -s
physcpubind: 0 1 2 3
No NUMA support available on this system.

2)"Look at the output of cat /proc/cpuinfo "physical id" indicates which cores are in which sockets"
In all four processors physical id    : 0

Furthermore whe I execute top command I can see:
 PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+     COMMAND 
 3022 root         20   0  238m  66m  45m   S  166         3.6       3:32.12     python


Is my GRC file only executing in one core? How can I find it out?
Any idea to fix it?

Many thanks,
Jorge