Re: balance by selecting host with lowest latency?

From: Wout Mertens <wmertens#cisco.com>
Date: Mon, 12 Dec 2011 12:14:09 +0100

Actually, I now realized the use of the "track" keyword so the second question is solved.

I did come up with a different feature request: Please provide an average queue time for the connections in a backend. It would be nice if an option could be set to log errors if the queue time exceeds x seconds too. I just had a configuration change result in a 30s queue time and I didn't realize it until someone complained :-(

Thanks,

Wout.

On Dec 12, 2011, at 8:41 , Wout Mertens wrote:

> Hi Willy,
>
> On Dec 9, 2011, at 19:03 , Willy Tarreau wrote:
>

>> Then I realized that setting a low maxconn on the servers was already doing
>> exactly what we want : once the maxconn is reached, connections get queued,
>> and the faster servers get more connections than the slower ones, following
>> a ratio which is *exactly* their response time ratio. So if one wants to
>> ensure fair response times between servers, a little bit of queuing is all
>> what's needed.

>
> This is very interesting. It would be a great addition to the configuration manual :-)
>
>
> Two vaguely related questions now that I have your attention:
>
> - Would it be possible to add the average response time for a server in the statistics page? It would be interesting to monitor that number.
>
> - When you have the same server in multiple backends, does each backend do checking separately, or does it share the info once you enable it? I have some backends with just the one server and I don't enable checking on it because I don't want to burden the server with extra connections.
>
> Thanks!
>
> Wout.
Received on 2011/12/12 12:14