Dmitry Grinberg wrote:
> Running extremely select-heavy application. Using
> Connector/J 3.0 we reached limitation of some sort
> using mysql version 4.0.x, that appears to be a
> limitation on how the full text search index is
> built in 4.0.x. So we tested the same on 4.1.x and
> found that index is built much better (queries
> that slowed down from 1 sec to 20 sec are running
> close to 1 sec again). But we had to upgrade to
> Connector/J 3.1, since mysql 4.1.x doesn’t work
> with Connector/J 3.0.x. Now that where my warning
> begins. Don’t use that combination (Mysql 4.1
> with Connector/J 3.1). It runs fine for 4-5 hours
> and then starts locking connections. I wasted a
> week (restarting the app every 4-5 hours) trying
> to find a problem somewhere else, but the code
> hasn’t changed in more then a year. So I
> reverted to Mysql 4.0.x and Connector/J 3.0.x and
> no problems since then. So it appears it’s not
> production ready version after all.
Dimitry,
Connector/J 3.0 works fine with MySQL-4.1, and we have quite a few customers in production with 3.1 and 4.1 together under heavy loads, so I'd take your warning with a bit of skepticism, only because it's not something we've heard from a lot of users, and you don't seem to tell the full story here :|
If you'd care to share details of your issues (you don't state what exact versions of either server of JDBC driver you're using, and you don't give us thread dumps of where connections are hung up), we'd sure like to fix them, as they seem specific to your environment. Without that level of information, I don't see how you can possibly expect anyone to magically fix things :(
-Mark
Mark Matthews
Consulting Member Technical Staff - MySQL Enterprise Tools
Oracle
http://www.mysql.com/products/enterprise/monitor.html