rajeev_bitspilani

 Profile Answers by rajeev_bitspilani 

• Dec 28th, 2009

 

Session performance can be improved by allocating the cache memory in a way that it can execute all the transformation within that cache size.

Mainly only those transformations are considered as a bottleneck for performance which uses CACHE.

Say for example:

We are using three transformation in our mapping-
1) Aggregator - using 1 MB for Indexing and 2MB for Data - Lets assume that after using the Aggregator cache calculator the derived value is 6MB.

Likewise use the cache calculator for calculating the cache size of all the transformation(which uses chache)
2) Joiner - 5MB
3) Look-up - 7MB

So, combining the total cache size will be 6MB+5MB+7MB = 18MB

So, minimum of 18MB must be allocated to the session cache. If we are allocating less memory to the session than the Integration service might fail the session itself.

So, for optimizing the session performance CACHE plays an important role.

Thanks. If you don't find my answer satisfactory please read
"Session Cache" chapter from Informatica guide, you will have a better picture.

--Rajeev

satoru

 Profile Answers by satoru 

• Jun 17th, 2010

 

the first thing before touching the cache of the session is doing a tuning and optimize your mapping.
The tuning is in the session in the mapping tab. It allows you to see which transformation is the heaviest. begin with sources and targets, aggregators and joiners, then the others.

The cache is the last thing you must modify.

If you want it to be quick you must also know that it's recomended to only have 3 integration services (IS) max.