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Determine Scratch Space to be allocated

Posted: Mon Jul 13, 2009 9:52 pm
by cdw
Hi,

We are in the design phase for an application and have the basic job designs ready.

The ADMIN team has requested for information on how much scratch space and resource disk space would we need for our project.

What is the best way to estimate this and provide requisite estimates?

We know the stages, datasets etc that we will be using. Based on this, we did a primary calculation of record length * no of records per stage type.
But during actual execution it is possible that several jobs may run in parallel. Also causing multiple stages (operator processes) to run in parallel.

How then do we determine the actual scratch and resource disk that should be sufficient during execution?

Regards,
Bakul

Posted: Tue Jul 14, 2009 1:42 am
by ArndW
You should also take into account the size of buffering between stages used (if your target is significantly slower than your source) as well as repartitioning, sorts (both implicit and explicit) and space used in lookups.