QLogic 10000 Series Realize Significant Performance Gains in Oracle RAC with QLogic FabricCache - Manual (Page 6)

SN0451405-00 rev. B 07/13 6
White PaPer
Summary and Conclusions
QLogic recommends using the QLogic 10000 Series Fibre Channel adapter
in an Oracle raC database with Oracle’s aSM feature and providing LUNs in
a multiple of the nodes in the raC cluster.
Oracle recommends four LUNs for a disk group and, for best cache
optimization, making the LUN quantity a multiple of the node quantity. at a
minimum, use the following LUN counts:
• two-node raC = four LUNs per disk group
– Server1 has cache ownership on LUNs 1 and 3
– Server2 has cache ownership on LUNs 2 and 4
• three-node raC = six LUNs per disk group
– Server1 has cache ownership on LUNs 1 and 4
– Server2 has cache ownership on LUNs 2 and 5
– Server3 has cache ownership on LUNs 3 and 6
• Four-node raC = four LUNs per disk group
– Server1 has cache ownership on LUN 1
– Server2 has cache ownership on LUN 2
– Server3 has cache ownership on LUN 3
– Server4 has cache ownership on LUN 4
repeat the pattern to ensure that the LUN caching is distributed evenly
across the LUNs. Because the Oracle aSM balances the i/O load across the
LUNs, this configuration provides the best caching performance.