Upstream least_conn behavior irregularity

[Ruslan Ermilov]

On Thu, Mar 21, 2013 at 12:03:59PM -0700, John Watson wrote:
>    Well doesn't make sense when theres >4 concurrent requests
>    At any given time there's around 12 active_connections, but sock-3 is
>    still never being used

Can you see a difference with only one worker process?

Currently, different workers have distinct counters of active connections.
It should be unnoticed under a high load.

>    On Thu, Mar 21, 2013 at 9:34 AM, John Watson <[1]john at disqus.com> wrote:
> 
>      Ohhhh... that makes complete sense now.
>      Had 4 workers.
>      Thanks!
> 
>      On Thu, Mar 21, 2013 at 4:47 AM, Ruslan Ermilov <[2]ru at nginx.com> wrote:
> 
>        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?