Re: jdbc-IBM Connection Manager-Servlets and sql handles

Alex --

Do you see a downside to asking IBM to enhance the
releaseIBMConnection() method to call Statement.close() on any open
statements?  Seems like if you assumed it would work that way, others
will too.  I don't see any justification for keeping the Statement alive
so it seems like the method should work as you first assumed.  It sort
of beats having hard-to-diagnose handle leaks for no good reason.

Did you have any discussions with IBM in this direction?

Gary

> Alex Garrison wrote:
> 
> We recently had an interesting problem that took some help from
> Rochester to pinpoint:
> 
> After several days of uptime, jdbc accross all web server instances
> in websphere would suddenly stop working.  All subsequent sql queries
> would fail, even those from interactive green-screen sessions.  Our
> only recovery would be to end and restart all websphere instances.
> The problem seemed to happen randomly, at any time of the day or
> night.  We were at a loss to explain the problem.
> 
> We sent a sql cli trace to IBM and found out that we were running out
> of free sql handles.  Long story short: You must call the
> Statement.close() method when you are finished with a statement.  If
> you return a connection back to the IBM connection manager with
> IBMJdbcConn.releaseIBMConnection() without closing all the statements
> on the connection, you will create a sql handle leak.  Eventually you
> just run out of sql handles and, wham, you are stuck.  We had assumed
> that the connection manager would clean up everything when we called
> the releaseIBMConnection() method - it does not.
> 
> So if any of your servlets are a little sloppy about calling
> Statement.close(), fix it.
> 
> BTW:  I would like to publicly thank the IBM guys that helped us nail
> this problem.  I would also like to mildly rebuke those at IBM gave me
> a hard time declaring this a severity 1 problem (I think bringing
> websphere to its knees on a dedicated e-commerce as/400 is severity
> 1).
> 
> 
> Alex Garrison
> agarrison@logtech.com
> (423)636-7213
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