The 64-bit-mode HiRDB can allocate a larger memory area than the 32-bit-mode HiRDB, thus reducing the number of input/output operations on databases and work tables and enhancing performance. Moreover, operating HiRDB in a 64-bit space enables the 32-bit space that was used previously by HiRDB to be allocated as an area for application operations, such as a common library. Figure 11-1 compares the 32- and 64-bit modes.

Figure 11-1 Comparison between 32- and 64-bit-mode HiRDBs