Hard Partitioning: Dynamic Domains - Oracle Solaris 10 System Virtualization Essentials - page 53

For the XSB configurations on the M8000/M9000, each quad has two PCIe slots,
while quads 00-0 and 00-2 are also able to access two disk drives each.
Figure 2.8 shows the complete crossbar interconnect on an M9000-64 with
only two domains configured; the specific domain pathways are highlighted. The
darker, thicker paths indicate secure and isolated paths for use only by the specific
domain. The orange path shows the board-to-board communication of Domain 1.
Notice how this configuration utilizes both Uni-XSB and Quad-XSB configured
system boards. The board that is configured in Quad-XSB mode has one XSB as-
signed to Domain 1 and two domains assigned to Domain 2; the fourth XSB is
a floater XSB, free to be assigned to any domain. The SC ASICs on that system
board ensure the complete isolation and security between each Quad-XSB.
Although Figure 2.8 shows boards spread out across the M9000-64 system, this
was done to make it easier to see the unique data pathways on the crossbar inter-
connect. In practice, domains should be built out of adjacent boards to minimize
memory access latency.
Figure 2.8 Multiple Domains on M9000-64
Table 2.2 shows the minimum and maximum latency for memory access on the
M4000 to M9000.