I would like to add few points to it, during pre-compilation process it creates an consistency token (not time-stamp) between bind package and load module.
Best way is to choose small CI size for random access and large CI size for direct access. Without specifying CISZ the defaults will be 4096 for data and 1024 for index. Remember these sizes are obtai...
1024 and 4096 are powers of 2. You could specify 1000 and 4000 but VSAM would actually use 1024 and 4096 although I'm not sure if the full 1024 would actually be available to you. Short answer is that since that is the number VSAM will use, 1000 or 4000 will not save you anything.