You can view and set it via EAS (it's the "Pending cache size limit" on the General tab of the Application Properties dialog). You need to restart the app for the change to be picked up.
You can also view and set it with MaxL:
query application appname get cache_size;
alter application appname set cache_size 1024MB;
Figuring out the optimal setting is trial an error - this affects aggregation and load performance. There is a guideline in the DBAG but my experience is it comes out too small for large databases (it hasn't changed since 2007 or thereabouts...).
I have found benefits of increasing this up to at least a couple of GB with large (100GB+) cubes before performance stops improving.