Posted: Wed Nov 13, 2002 11:37 am
I believe the preload option uses the Hash File Stage Read/Write Cache sizes to determine whether or no it will preload the hash table.
Using DataStage Admin, check the project properties under Tunables for the Hash File Read/Write Cache size. By default, it is 128MB.
If the server has enough cache, it will preload. Check your DataStage log for the job to see if the cache is turned on or off.
In addition, under DataStage 6, you can possibly use Row Buffering to help speed up performance. This can be turned on at the Job level (Job Properties) or the Server level (properties - performance). I have found Row Buffering to be a good performance enhancer more so that preloading hash files into memory. There are two different types of Row Buffering. In Process and Inter Process. Check help to see which may be more applicable for you.
Kevin Janes
Using DataStage Admin, check the project properties under Tunables for the Hash File Read/Write Cache size. By default, it is 128MB.
If the server has enough cache, it will preload. Check your DataStage log for the job to see if the cache is turned on or off.
In addition, under DataStage 6, you can possibly use Row Buffering to help speed up performance. This can be turned on at the Job level (Job Properties) or the Server level (properties - performance). I have found Row Buffering to be a good performance enhancer more so that preloading hash files into memory. There are two different types of Row Buffering. In Process and Inter Process. Check help to see which may be more applicable for you.
Kevin Janes