|
Mass Parallelism The IBM XIV system's revolutionary approach ensures that all disks and modules are used equally, regardless of access patterns. The system keeps the load perfectly balanced, even if certain applications access certain volumes, or certain parts within a volume, more frequently. The pseudo-random distribution ensures consistent load-balancing, even after volumes are added, deleted or resized, or hardware is added or removed.
Unique Cache Architecture
Unlike any other storage system, the IBM XIV system's design embeds the read/write cache into the same hardware module as the disks. This has distinct advantages:
Distributed cache. All cache units can concurrently serve host I/O and perform cache-to-disk I/O ensuring that the cache will never become a bottle-neck.
High cache-to-disk bandwidth. Cache-to-disk bandwidth is the internal bandwidth of a module. Implemented over two PCI-X buses, a module thus provides dozens of gigabytes per second for the whole system.
Powerful cache management. The unique IBM XIV design enables the system to read a large cache slot per disk read, while managing least-recently-used statistics in small cache slots. This dual capability is made possible by the combination of the XIV system's huge processing power and high cache-to-disk bandwidth.
Massive CPU Power
The fact that each data module has its own processing power provides the IBM XIV system with dozens of powerful CPUs. This power is used for sophisticated caching algorithms, support for small cache slots, snapshot performance, and so on. IBM XIV also offers dual processors in its interface modules, enabling up to a 30% increase in performance, depending on workload. The massive CPU power ensures high performance through higher cache hit rates and smaller snapshot overhead. Consistent Performance The IBM XIV system's revolutionary new architecture is designed for consistent performance. Its distributed rebuild approach and avoidance of cache write-through keep its high performance consistent through any hardware failure.
|
