I made some configuration changes to the WebSphere server that is hosting our eBusiness application. I changed the WebContainer thread count to something more reasonable (Min 7) than what it was (Min 300), and I also set the initial java heap size to be 250 MB instead of the 32 it was at, since the server is hanging around the 100 MB to 300 MB range. We'll see if those changes have any effect.
Using Snapshot Isolation with SQL Server and Hibernate
In the course of working on some deadlock issues, I found that MS SQL Server exhibits some unexpected (to me, at least) locking behaviors that can affect performance and cause deadlocks. In the end, I found that SQL Server provides an isolation level called Snapshot isolation which removes the need for locks on rows and removes lock contention. To use this isolation level, you need to execute the following SQL on the database that you want to use the isolation level with (replacing MyDatabase with your database name, of course): ALTER DATABASE MyDatabase SET ALLOW_SNAPSHOT_ISOLATION ON ALTER DATABASE MyDatabase SET READ_COMMITTED_SNAPSHOT ON Next, you need to modify your hibernate.cfg.xml file to add a property to tell Hibernate to use the Snapshot Isolation level: <!-- The 4096 isolation level is the setting to use with the jTDS or Microsoft JDBC drivers --> < property name =”hibernate.connection.isolation”>4096</property> Snapshot isolation is not a panacea...
