Re: [Babeldoc-devel] perils of synchronization in PooledJdbc.java

[Bruce M. <br...@mc...>]

Jonathan,

I haven't heard from you in some time - how is it going?   The work that you 
have done on babeldoc in recent weeks and months has been excellent.  I am 
hoping to see your work on the xml entity resolver.

regards,
Bruce.

On Thursday 10 July 2003 06:42 pm, Leech, Jonathan wrote:
> I think we need to remove synchronization from the checkIn() and checkOut()
> methods of PooledJdbc.java, and here's the reason why: It causes deadlock
> every time the connection pool is exhausted.
>
> Example:
> - All database connections in the pool are being used by various threads.
> - A thread calls checkOut(), which locks the PooledJdbc object, and the
> connection pool is waiting for a checkin.
> - As the various threads finish using their database connections, they call
> checkIn(), but are locked out.
>
> The only problem I see with it doing it is that there's a chance that
> multiple threads could ask for the first connection, which calls
> setupJdbc(), and that might be not well behaved.  I think moving the
> setupJdbc to the default constructor would handle this.
>
> Thoughts?
>
> -Jonathan