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From: Jim Jagielski <jim@jaguNET.com>
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Subject: Re: strange usage pattern for child processes
Date: Mon, 20 Oct 2008 09:55:37 -0400
References: <20081015115548.GA9872@eilebrecht.net> <48F651DE.5060003@sharp.fm>
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On Oct 19, 2008, at 4:20 PM, Ruediger Pluem wrote:

>
>
> On 10/19/2008 07:35 PM, Jim Jagielski wrote:
>>
>> On Oct 18, 2008, at 4:22 PM, Graham Leggett wrote:
>>
>>> Ruediger Pluem wrote:
>>>
>>>>> As a result, the connection pool has made the server slower, not
>>>>> faster,
>>>>> and very much needs to be fixed.
>>>> I agree in theory. But I don't think so in practice.
>>>
>>> Unfortunately I know so in practice. In this example we are seeing
>>> single connections being held open for 30 second or more. :(
>>>
>>>> 1. 2.0.x behaviour: If you did use keepalive connections to the  
>>>> backend
>>>>  the connection to the backenend was kept alive and as it was bound
>>>> to the
>>>>  frontend connection in 2.0.x it couldn't be used by other  
>>>> connections.
>>>>  Depending on the backend server it wasted the same number of  
>>>> resources
>>>>  as without the optimization (backend like httpd worker, httpd
>>>> prefork) or
>>>>  a small amount of resources (backend like httpd event with HTTP or
>>>> a recent
>>>>  Tomcat web connector). So you didn't benefit very well from this
>>>> optimization
>>>>  in 2.0.x as long as you did not turn off the keepalives to the
>>>> backend.
>>>
>>> Those who did need the optimisation, would have turned off  
>>> keepalives
>>> to the backend.
>>>
>>>>
>>
>> Trying to grok things better, but doesn't this imply that
>> for those who needed the optimization, disabling the
>> connection pool would be the required work-around for 2.2?
>
> No. Without a connection pool (e.g. the default reverse worker) the  
> backend
> connection does not get freed any faster than without a connection  
> pool.
> Ok strictly spoken you cannot turn off the connection pools at all  
> (reverse
> is also one), you can only turn off a reuse of the connections.
>

I thought that was the concern; that the pool wasn't released
immediately. If you disable reuse, then you don't need to
worry about when it is released... or I must be missing something
obvious here :/