Specifications

HP Instant Capacity

HP iCAP is a means of adding and removing processors in a partition. With iCAP, you do not need

to worry about:

• Interleaved memory

• Application locked memory

• Server switchovers due to false failures

• Physically handling processors or memory boards

• Rebooting

iCAP is the most reliable means of reducing planned downtime for hardware upgrades.

Memory protection

Main memory failures are the single largest cause of customer downtime. The HP 9000 rp7440 and

rp8440 Servers have several features designed to reduce failures of memory:

• Double Chip Spare (DCS)

• Dynamic memory resiliency (DMR)

• Automatic deconfigure on reboot

• Hardware memory scrubbing

• Industry leadership address/control parity protection

Double Chip Spare

The HP 9000 rp7440 and rp8440 Servers support extensive state-of-the-art error detection and error

correction features. This protection is used on paths within the VLSI components and between the

chipset components and processors, memory, and I/O, including processor buses, memory buses,

I/O and fabric links, and I/O slots.

An enhanced feature in the sx2000 chipset over the sx1000 chipset is the DCS. This capability of the

memory error correcting logic reestablishes chip spare correction after another DRAM in the same

ECC codeword has failed. With DCS, firmware recognizes when the first DRAM has failed and

deletes its bits from the ECC calculations, which enables the ECC logic to correct for a second DRAM

failure in the same ECC codeword. This erasure can be applied to a single DRAM, all DRAMs sharing

a bit of a bus, or all buses of a memory subsystem. This maximizes the coverage of this unique

protection mechanism. This enhanced feature is a result of the HP advance research in memory

technology and does not require more DRAMs per MB than was required for the sx1000 single chip

sparing support. This strategy is more cost-effective than memory mirroring methods for protecting

memory. The primary benefit of this HA feature is that it reduces system downtime to replace failed

DRAMs.

Dynamic memory resiliency

DMR is the ability of the system to de-allocate failed memory pages online. This feature is similar to

DPR; if a location in memory proves to be questionable (that is, exhibits persistent errors), the memory

is de-allocated online with no visible impact. Assuming the HP 9000 rp7440 and rp8440 Servers are

equipped with adequate memory to begin with, it is unlikely that the failed memory might have to be

replaced over the life of the product, resulting in a significant reduction in both planned and

unplanned downtime. DMR is superior to industry available hardware-only techniques because

hardware-only techniques can quickly run out of spares. The HP page deallocation technique solves

this problem, resulting in more spares than can possibly be used over the life of the machine.

Hardware memory scrubbing

Software-based memory scrubbers are limited in function because many operating systems and

applications “lock down” memory, resulting in no possible access. The HP hardware scrubber