tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Alan Chaney <a...@compulsivecreative.com>
Subject Re: R: How to close idle connections
Date Mon, 28 Apr 2008 14:59:34 GMT


David Smith wrote:
>>
>>
>> No, I have at most 20 idle connections, that's goes right, but my boss 
>> want
>> less idle connections to avoid to overload the database server. So there
>> isn't way to close an idle connection to remove the relative process?
>> If so, I will set maxIdle="2" and everyone will be happy (expecially 
>> me :)
>>  
>>
> 
> 
> I'll bet money the added, idle postgres connections are just sleeping 
> while they wait for work.  Given idle connections contribute virtually 
> no additional load, don't see his argument that idle connections 
> contribute to a database overload.  If the minor increase in overhead 
> due to sleeping threads actually overloads the database, you need to let 
> your boss know the server hardware is way too frail for production use 
> and needs to be upgraded.
> --David
> 
Agreed. I use postgres and with ps alx | grep postgres each connection 
shows as idle (when its not being used!) and consumes about 140k bytes 
of memory. On a modern server that can hardly be considered as any use 
at all!


Alan Chaney




> Enrico Sasdelli wrote:
> 
>> Thanks for reply,
>>
>>  
>>
>>> I see you have maxIdle="20".  Do you have more that 20 connections 
>>> sitting idle?  Is this really that much of a concern?  As long as the 
>>> connections are released (closed) and returned to the pool, I don't 
>>> see the problem.
>>>   
>>
>> No, I have at most 20 idle connections, that's goes right, but my boss 
>> want
>> less idle connections to avoid to overload the database server. So there
>> isn't way to close an idle connection to remove the relative process?
>> If so, I will set maxIdle="2" and everyone will be happy (expecially 
>> me :)
>>
>>
>> Thank you,
>> Enrico
>>
>>
>>  
>>
>>> The entire idea of a connection pool is the system keeps around a set 
>>> of idle connections for borrow.  When you code get's a connection, it 
>>> comes   
>>> from the pool of idle connections and returned when you close the 
>>  
>>
>>> connection.  This speeds up your application by elliminating the 
>>> overhead of contacting the server and constructing a new connection 
>>> whenever you call for one.  The pool just grabs a pre-made one off 
>>> the shelf for you.
>>>   
>>
>>  
>>
>>> --David
>>>   
>>
>> ---------------------------------------------------------------------
>> To start a new topic, e-mail: users@tomcat.apache.org
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>>
>>
>>  
>>
> 
> 
> ---------------------------------------------------------------------
> To start a new topic, e-mail: users@tomcat.apache.org
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
> 
> 
> 
> !DSPAM:4815ddca16721381456296!
> 

---------------------------------------------------------------------
To start a new topic, e-mail: users@tomcat.apache.org
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Mime
View raw message