Upstream least_conn behavior irregularity

[Ruslan Ermilov]

On Thu, Mar 21, 2013 at 01:45:14AM -0700, John Watson wrote:
>    Was investigating some issues today when we noticed that least_conn wasn't
>    behaving as expected.
>    upstream backend {
>      least_conn;
>      server unix:/tmp/sock-1.sock;
>      server unix:/tmp/sock-2.sock;
>      server unix:/tmp/sock-3.sock;
>    }
>    The expected behavior for 4 simultaneous requests it should distribute
>    them:
>    sock-1: 2
>    sock-2: 1
>    sock-3: 1
>    However, what we're seeing is:
>    sock-1: 3
>    sock-2: 1
>    sock-3: 0
>    Which coincidentally lines up with the number of requests a socket can
>    service simultaneously.
>    This is using 1.2.7

And the number of configured worker processes is?