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Comment by ceequof | Hacker News Reader

In the terminal snippets, latency is specified in "us", which I'm guessing is µs, microseconds.

In the table, those latency numbers are specified in "ms". Also microseconds? Couldn't possibly be milliseconds, for two VMs that should only be a couple dozen metres away from each other, right?

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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.

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