Posts

Showing posts from August, 2011

Very Large Migrations

Image
Most of the time SQL Developer does a good job of migrating a database from SQL Server, Sybase ,... To Oracle. But there are some tricks to help make very large migrations perform smoother. This talks about Large migrations in terms of object numbers , not amount of data in tables. If your migrating 50 databases at once, and each has 1,000 tables, 1,000 views , 1,000 procedures . That is a lot of meta data to churn through and sometimes we find memory issues , open cursors ,... can be a problem. We are always working to reduce the amount of resources required to perform the migrations , but for the moment (SQL Dev 3.0) here are a few tricks which just might make the difference between the migration failing and the migration completing. Memory By Default SQL Developer startups with AddVMOption -XX:MaxPermSize=128M (found in sqldeveloper\sqldeveloper\bin\sqldeveloper.conf) AddVMOption -Xmx640M (found in sqldeveloper\ide\bin\ide.conf) AddVMOption -Xms128M (found in sqldev