Wow, huge mea culpa on that one. I would assume that qperf is using us to mean microseconds, and judging by the source line

    char *tab[] ={ "ns", "us", "ms", "sec" };

it would certainly seem that way. I'll update the post, thanks.

Now I'll just be waiting for someone to complain about inconsistent precision. I am not a good scientist...

yes, microseconds surely - we estimate that the cost of switching from kernel to user space, and back again, several times, adds up to 2-300 microseconds. in return for this, you gain a lot of flexibility and ease of use. for apps that need lower latency, weave is currently working on implementing a fast data path option..

I think they are supposed to be 'us' based on the qperf output.