Difference between RAM blocks and Memory Bits?

In report.html it also says:

Load uses a Burst-coalesced cached LSU. Load with a private 512 kilobit cache. Cache is not shared with any other load. It is flushed on kernel start. Use Dynamic Profiler to verify cache effectiveness. Other kernels should not be updating the data in global memory while this kernel is using it. Cache is created when memory access pattern is data-dependent or appears to be repetitive. Simplify access pattern or mark pointer as 'volatile' to disable generation of this cache.

what that mean? I try to mark my temp as

volatile B_parallel temp;

and it give a lot of error while Linking with IP library