Advanced ecc memory population guidelines, Online spare memory population guidelines – HP ProLiant DL580 G7 Server User Manual
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Hardware options installation 50
AMP modes are configured in RBSU. If the requested AMP mode is not supported by the installed DIMM
configuration, the server boots in Advanced ECC mode. For more information, see "HP ROM-Based Setup
Utility (on page
)."
For the latest memory configuration information, see the QuickSpecs on the HP website
Advanced ECC memory population guidelines
Advanced ECC memory is the default memory protection mode for the server. Up to 1 TB of active memory
using 16-GB DIMMs is supported in this AMP mode.
Using (E7) processors, up to 2 TB of active memory using 32-GB DIMMs is supported in this AMP mode.
Advanced ECC can correct single-bit and multi-bit memory errors on a single x8 or two adjacent x4 DRAM
devices.
The server provides notification when correctable error events have exceeded a pre-defined threshold rate.
When uncorrectable errors are detected using Advanced ECC, the server notifies the user and shuts down
the operating system.
Online Spare memory population guidelines
Online spare memory provides protection against persistent DRAM failure. It monitors DIMMs for excessive
correctable errors and copies the content of an unhealthy rank to an available spare rank in advance of
multi-bit or persistent single-bit failures that may result in uncorrectable faults. Rank-sparing is more efficient
than DIMM-sparing since only a portion of a DIMM is set aside for memory protection.
When Online Spare memory is enabled, the first ranks of DIMM pair, 1A/8A, are set aside as the sparing
ranks. Therefore, the available memory is reduced by the size of the first ranks of DIMM pair 1A/8A.
If a DIMM rank on either of the SMI buses exceeds its correctable ECC threshold, then the contents of the
failing DIMM ranks are copied to the spare DIMM ranks. Once the copy is complete, all memory accesses
to the previous failing DIMM ranks go to the spare DIMM ranks.
No performance penalty occurs for rank-sparing, other than the time it takes to copy the data from the failing
rank to the spare rank upon an error condition.
The following population rules apply to each memory cartridge. Begin with the DIMM installation guidelines
) with these additional constraints:
•
All installed processors must contain a valid sparing configuration.
•
If installing mixed rank DIMMs in a cartridge, follow the mixed rank installation rules of the DIMM
installation guidelines (on page
•
Rank sparing requires that the spare ranks of the DIMM pair 1A/8A be at least as large as any other
DIMM rank on the DDR3 channels of the cartridge. To determine the size of a single rank in a DIMM,
divide the total DIMM size by the number of ranks.
For example, the rank size of a dual-rank 2-GB DIMM is 1 GB and the rank size of a dual-rank 4-GB
DIMM is 2 GB. Therefore, it is possible to support rank sparing with mixed DIMM pair sizes in the
cartridge if the 1A/8A pair is populated with the 4-GB DIMMs and the other pairs are populated with
either the identical 4-GB or 2-GB DIMMs (pairs C and D are not required to be populated). In this case,
the 2-GB rank size of the 4-GB DIMMs in the 1A/8A pair is equal to or greater than the rank size of the
other installed DIMMs.