Re: Tuning IDS 9.30 after migration from IDS7.31

Hi Dave, We migrated from informix 5.x to IDS 9.21 . We also had a lot of performace issues. The main reasons for our problems were - 1) Informix 5 did not have OPTCOMPIND param . In 9 we used 2 , a lot of queries started doing sequential scans instead of indexed reads. After changing this to 0, it was ok more or less. In ur case, u might not have changed OPTCOMPIND, but it would be advisable to check the main queries of the application which slowed down and then run these queries with explain on IDS 7 and 9 to see if there is any difference. 2) We had to increase resources ( buffers especially ) to get to the informix 5.x performance. You can also try to create a new database and physically load the data from ur migrated database and check the performance ( In place migration might be different from this ) or u can try to drop and re-create indexes ( assuming inplace migration did not do that ). Rgds Preetinder >Dave Thacker > > sending to informix-list