Re: Rails app with maxconn 1 receiving more than 1 request at a time

We've been experiencing the same thing with 1.3.15.2: http://skitch.com/codyfauser/i5kc/shopify-haproxy

On Fri, Sep 12, 2008 at 9:23 PM, Mark Imbriaco <mark#37signals.com> wrote:

>
> For the record, I have seen this as well lately. I was planning to report
> it when I had time to dig up more data, but Rupert beat me to it. Here's
> an example of what I see on one of my instances:
> http://skitch.com/signalmark/i5j1/haproxy-maxconn-bug
>
> I'm wondering if this is a regression in 1.13.3.3 since I don't see
> similar numbers in the HAproxy stats on 1.13.3.2.
>
> -Mark
>
>
> On Sep 12, 2008, at 9:04 PM, Brian Gupta wrote:
>
> I am confused why you are seeing more "max" sessions than "limit"
>> sessions. This shouldn't be happening.
>>
>> -Brian
>>
>> On Fri, Sep 12, 2008 at 8:44 PM, Rupert Fiasco <rufiasco#gmail.com>
>> wrote:
>>
>>> The max conns on the stats seems to be crazy high.
>>>
>>> http://brockwine.com/images/haproxy_stats.png
>>>
>>> Also, what constitutes an error/warning? I seem to be seeing a lot of
>>> those as well. Does that mean by backend is returning a bunch of HTTP
>>> 500 or is it an internal haproxy error/warning?
>>>
>>> Thanks
>>> -Rupert
>>>
>>> On Fri, Sep 12, 2008 at 5:15 PM, Brian Gupta <brian.gupta#gmail.com>
>>> wrote:
>>>
>>>> Curious, what is the haproxy stats page reporting for maxconns for the
>>>> individual backends? IE: Is haproxy also seeing peaks of high
>>>> connection counts?
>>>>
>>>> -Brian
>>>>
>>>> On Fri, Sep 12, 2008 at 8:03 PM, Rupert Fiasco <rufiasco#gmail.com>
>>>> wrote:
>>>>
>>>>> We are running 1.3.15.3 and have haproxy in front of a cluster of
>>>>> mongrels. We have a plugin in the mongrels that displays the mongrels
>>>>> current queue length.
>>>>>
>>>>> With a haproxy config line like:
>>>>>
>>>>> server server-0 127.0.0.1:9000 maxconn 1 check inter 30s slowstart 10s
>>>>>
>>>>> This should mean that haproxy will *NEVER* send more than 1 request to
>>>>> that backend. Yet our plugin is reporting that it has sometimes 10+
>>>>> requests queued up.
>>>>>
>>>>> Is my config wrong?
>>>>>
>>>>> Thanks
>>>>> - Rupert
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> - Brian Gupta
>>>>
>>>> http://opensolaris.org/os/project/nycosug/
>>>>
>>>> http://www.genunix.org/wiki/index.php/OpenSolaris_New_User_FAQ
>>>>
>>>>
>>>
>>
>>
>> --
>> - Brian Gupta
>>
>> http://opensolaris.org/os/project/nycosug/
>>
>> http://www.genunix.org/wiki/index.php/OpenSolaris_New_User_FAQ
>>
>>
>
>

-- 
Cody Fauser
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