Largest buffer pool under Adabas version 7?

Hi, We have an LBP of 200 meg, and an efficiency of around 14. I am planning on trying out incremental increases to the LBP and seeing if I get any improvement, but wondered how high I could go without negative effects (assuming there is no paging). Has anyone used an LBP as high as 400 meg?

On 1 of my nuclei I am using a 700MB buffer pool backed up by 8GB of ADABAS cache.

Version is 7.4.4.