Everything was working fine until an upgrade on AS400 to O/S 5.1. The remote queries have dramatically slowed down.
We can see the job opening the SYSTABLES and SYSCOLUMNS files which contain an entry for every AS400 file and field respectively. Obviously these are very large files. Right at the end of the processing the target data file is opened momentarily. This doesn't happen on servers without the upgrade.
Why is it doing this? Can we stop it? Is there a config setting which needs to be changed? On db2? On the AS400?