Hitachi 9900 Series User Manual
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Advanced Cache Algorithms of the Lightning 9900 Series ......................................................................18
Hitachi FlashAccess Allows Datasets to be Permanently Placed in Cache ................................................18
Read-ahead for High-performance Sequential Reads ................................................................................18
The Control Memory Hierarchical Star Network ....................................................................................18
Chapter 5 – High Performance Back-end Design____________________________________________21
High-Performance Back-end Design ........................................................................................................21
New Fibre Channel Disk Drives ..............................................................................................................21
Maximum Configuration of ACPs and Disks ..........................................................................................22
The Importance of Command Tag Queuing (CTQ) ................................................................................22
Chapter 6 – Capacities and RAID Architecture ____________________________________________23
Storage Capacity of the Lightning 9900 Series ........................................................................................23
Advantages of the Lightning 9900 Series RAID Hardware ......................................................................23
RAID-1+ ..................................................................................................................................................23
RAID-5 Distributed Parity ......................................................................................................................23
RAID Rebuild Capability ........................................................................................................................23
High-density Disk Drive Assemblies (HDDs) ..........................................................................................24
Chapter 7 – Hitachi High-Availability Software Improves Application Service Levels ______________25
An Overview of High Availability (HA) Computing Software..................................................................25
Software products contribute to High-Availability Computing ................................................................25
The Lightning 9900 has an Advanced Availability Profile compared to Competitive Products ................25
Open Systems High-Availability Middleware Support ..............................................................................26
1 - Alternate Pathing middleware switches the I/O load in the event of path failure ........................27
2 - Hitachi Dynamic Link Manager provides path failover and load balancing ................................27
3 - Host Failover................................................................................................................................27
4 - Parallel Database Clustering ........................................................................................................28
Standard Hot-swap and Redundant Power Supplies ................................................................................28
Standard Redundant Fans for Cooling......................................................................................................29
Unmatched Competitive Advantage in RAID Choices ............................................................................29
Chapter 8 – Performance Considerations __________________________________________________31
Truly Scalable Performance ......................................................................................................................31
The Advantages of the Lightning 9900 Series Hi-Star Architecture Over a Shared Bus Architecture ........31
Internal Switching Overcomes the Limitations of Shared Bus Architectures ............................................32
Test Results ..............................................................................................................................................32
Hitachi Data Systems
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