Can anyone please explain in english the difference between blocked and
non-pages in a bufferpool.

What would be a typical ration one would use for say a 100,000 4kb size
BP. 50/50 blocked v unblocked ?

Applications that employ sequential prefetching can benefit from
improved performance through the use of blockbased buffer pools, which
allow blocks of contiguous pages to be moved into contiguous portions
of memory. Keep in mind that block-based pages will be wasted if your
application doesn't perform sequential prefetching.

Typically, SQL statements that do table scans large tables will do
sequential prefetching Blockbased buffer pool pages should not be used
for OLTP applications or whenever sequential prefetch is not common.

Where you have large data warehouse tables that are often accessed via
full table scans, you can place those tables in tablespaces that are
specifically linked to bufferpools with block based pages.