commons-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Aitor Imaz" <Aitor.I...@donewtech.com>
Subject Re: [DBCP] getNumActive() returns a negative value
Date Wed, 03 Sep 2003 08:59:21 GMT
I'm still getting random ObjectIsClosedExceptions once in a while using
the nightly build (31/8), although not very often. If I'm not wrong this
nightly build uses the wrapper that checks for double-closing
connections, so I can't understand why I'm still getting a negative
value when I call getNumActive(). Shouldn't the patch deal with this
issue?

I'm doing what the Tomcat example says, except that inside the catch
block I am closing the resultset and statement and doing a rollback on
the transaction (and setting the connection to null). I wonder if this
has something to do with the negative numActive value. Should I rely on
the finally block instead?

I see your point on returning an SQLException indicating something is
wrong, but the problem is I'm logging the exceptions and my log file
grows considerably as I'm getting lots of "Already closed"
SQLExceptions. I guess this is more of an issue with the way I save the
thrown exceptions, though.

I'm afraid we haven't thoroughly load-tested our application (and
therefore DBCP). I am using a load test simply to simulate the race
condition and make the app fail.

Cheers,
Aitor



Dirk Verbeeck wrote:

>Negative getNumActive() is a clear sign that you are returning your 
>connections to the pool twice.

>In v1.0 this was possible due to a race contition in close (issue
16987) 
>like you found.

>The problem with the SAP jdbc driver exception can be a result of
>http://issues.apache.org/bugzilla/show_bug.cgi?id=22079 
><http://nagoya.apache.org/bugzilla/show_bug.cgi?id=22079>

>Both issues are solved in the latests build.

>Are you getting the ObjectIsClosedException in the nightly build ?

>Like Jamie said, the tomcat example is correct, see also my examples...

>I know that the spec specifies a no-op but a SQLException is allowed
and 
>shows where something goes wrong.
>The behaviour is unchanged since 1.0 but now you will get it always
when 
>returning a connection twice.

>I'm very interested in the stability and speed results.
>Can you compare v1.0 and the latest under high load?

>Cheers
>Dirk



---------------------------------------------------------------------
To unsubscribe, e-mail: commons-user-unsubscribe@jakarta.apache.org
For additional commands, e-mail: commons-user-help@jakarta.apache.org


Mime
View raw message