Re: Communications link failure due to underlying exception...various network exceptions

[Mark Matthews]

mreichman Wrote:
-------------------------------------------------------
> Mark Matthews Wrote:
> --------------------------------------------------
> -----
> > What happens if you run with
> > "useServerPrepStmts=false"? It looks like the
> > connection is going away while the driver is
> > trying to read results, which often is one of
> two
> > things...The server is crashing, or your client
> is
> > reading rows slower than the timeout
> > 'net_write_timeout' on the server.
> >
> > Disabling server-side prepared statements
> usually
> > takes care of the former (and in fact, they're
> > disabled by default in 5.0.5 and later).
> >
> > -Mark
>
> I'm just starting to experiment with that option.
> If the server crashed, it would be indicated in
> the log or at least Windows Event Log, right? How
> would I tell about the second possible condition?

Yes, you should see server crashes or unexpected restarts in either the error log or Windows Event log (depending on version and how you have it configured).

As for the second possible condition, you'd either have to "know" your application, i.e. is it using "streaming" result sets, does it run into long stop-the-world GC events, etc. or you can change the value of net_write_timeout on the server to something very high and see if the problem goes away.

>
> Finally, is there an ETA for when 5.0.5 is out?

Within a week or so, it's just going through testing now (there's a matrix of around 25,000 tests on various platforms, MySQL server versions and JDK versions that we run), and once we get that all passing we'll do a release. It usually takes a week or so to get through this process.

-Mark

Mark Matthews
Consulting Member Technical Staff - MySQL Enterprise Tools
Oracle
http://www.mysql.com/products/enterprise/monitor.html