The timeout is also how WL pools work. They offer a (IIRC) flag to
allow shrinking, a time period of inactivity to wait before shrinking,
and a minimum size to shrink to. Any time I was running with a firewall
bewteem the app server and the database I alwasy used this - with the
min at 0 so they would all close out during periods of inactivity (which
is when the firewalls would try to whack the connections anyway.)
-tom
Chris Audley wrote:
>
> There reaches a point where the overhead of checking the connection to the
> database is on the same order of magnitude as just opening a new connection.
> If you're reading metadata and doing queries, I think you've reached that
> point. You might as well just ditch connection pooling.
>
> I think object timeouts are the way to go. Not only do they clear out
> connections that may have gone stale, but with commercial RDBMS, you pay for
> concurrent connections. Idle pooled connections waste money.
>
> I was actually surprised to find out that Minerva didn't provide a timeout
> for pooled objects. All of the mechanics are there, the last time an object
> was used is reported and a GC thread is run periodically. All thats needed
> is a stale object timeout ( there are already two, I though GCMinIdleTime
> was cleaning out stale objects ), and the logic in the GC method.
>
> Cheers
> Chris Audley
> Urbanfetch.com
>
> -----Original Message-----
> From: Aaron Mulder [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, September 14, 2000 12:03 PM
> To: jBoss
> Subject: Re: [jBoss-User] JDBC Connection reset by peer
>
> That's not going to work either. For one thing, it might take
> some effort to locate a table the user has select privileges on (we can't
> really tell an access denied SQLException from a collection to DB lost
> SQLException). But more importantly, I've seen Oracle instances that were
> so bloody complex that it took minutes to load the database metadata.
> Now you might argue that that represents poor database design, but it's
> not up to you.
> We could maybe let the user specify a table and then execute a
> "select 'x' from foo where 0=1" or something. But I kind of liked the
> other idea about just timing out the connections if they've been idle too
> long.
>
> Aaron
>
> On Thu, 14 Sep 2000, Rick Horowitz wrote:
> > I'm not 100% sure of the problem you're trying to solve here, but would
> > it be possible to use one of the JDBC connections to read the database
> > metadata, and from that create a JDBC query that could be executed to,
> > for example, just read some data from one of the tables?
>
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