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From Dirk Verbeeck <>
Subject Re: DBCP maxActive does not set limit?
Date Sat, 09 Apr 2005 08:46:29 GMT
You are correct that the maxActive limits the total number of connections.
Can you check the number of connection on the oracle database itself?
select * from v$session
How many network connection are there at the end of the test?
Also try to set maxIdle to 50 and test again.

-- Dirk

jgelb wrote:
> All:
> Sorry if this is the wrong place -- I tried to check the archives first 
> and get the faq and info from the list itself, but none of that was 
> working, and I'm not finding anything via google (yet).
> I'm seeing something that I don't understand when using DBCP in Tomcat 
> (5.0.27 and 5.0.28) and I was wondering if anyone familiar with the code 
> might be able to enlighten me.
> Specifically, during load tests netstat is showing me that I have more 
> TCP connections in ESTABLISHED state than my maxActive settings -- 
> sometimes -many- more.
> In one test contrived to excercise the pool and nothing else, I set 
> maxActive to 50 and then ran through 20000 requests (70 simultaneous 
> requestors).  At one point I saw 198 connections to my database.
> I understand that network connectivity doesn't necessarily correlate 
> directly to a database connection, but if the pool really is limiting 
> itself to maxActive connections, I don't understand why I'd ever see 
> more than maxActive established network connections.
> Fwiw, observations were on redhat linux ES 3 (using 2.4.21 kernel?) and 
> a gentoo linux build using a 2.6.9 kernel, using oracle and postgres as 
> the backends.
> Any insight or comments much appreciated.
> -- jeff gelb

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