cocoon-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Andrew C. Oliver" <acoli...@apache.org>
Subject Re: SQLTransformer bug that appears under load
Date Mon, 08 Apr 2002 12:06:27 GMT
A Dangerous fix.  But if I had to speculate:  I imagine conn.close() is
synchronized.  Secondly, I imagine its logged.  Cause this to be a
warning (not be logged) and there should be a performance increase.. 
Cause conn.close() to not be synchronized (haven't looked...just a
guess) and there should be a performance increase.  close() probably
doesn't need to be synchronized necessarily.  (again, just guesses).

-Andy

On Mon, 2002-04-08 at 03:38, neil wrote:
> I've been load testing my cocoon app with jmeter and I think I've found a
> SQLTransformer bug.
> My (MS SQL Server) JDBC driver was complaining about attempts to use various
> objects after they had been closed (Connections, ResultSets and Statements).
> 
> In Query.execute() I think this bit should be removed:
>             } finally {
>                 conn.close();
>                 conn = null;        // To make sure we don't use this
> connection again.
>             }
> 
> as it's incorrect to close the connection before you've finished with the
> ResultSets, Statements etc.
> The connection is closed later when SQLTransformer.executeQuery() calls
> Query.close() anyway.
> 
> I know Connection.close() doesn't really close the connection to the DB
> (because its a pooled connection it just allows it to be recycled), but I
> think its reuse under load does cause problems. By removing these lines I
> was able to get my app to work correctly under heavy loads on a dual CPU
> Windows 2000 box.
> 
> 
> ---------------------------------------------------------------------
> Please check that your question has not already been answered in the
> FAQ before posting. <http://xml.apache.org/cocoon/faqs.html>
> 
> To unsubscribe, e-mail: <cocoon-users-unsubscribe@xml.apache.org>
> For additional commands, e-mail: <cocoon-users-help@xml.apache.org>
> 
-- 
http://www.superlinksoftware.com
http://jakarta.apache.org/poi - port of Excel/Word/OLE 2 Compound
Document 
                            format to java
http://developer.java.sun.com/developer/bugParade/bugs/4487555.html 
			- fix java generics!
The avalanche has already started. It is too late for the pebbles to
vote.
-Ambassador Kosh


---------------------------------------------------------------------
Please check that your question has not already been answered in the
FAQ before posting. <http://xml.apache.org/cocoon/faqs.html>

To unsubscribe, e-mail: <cocoon-users-unsubscribe@xml.apache.org>
For additional commands, e-mail: <cocoon-users-help@xml.apache.org>


Mime
View raw message