Memory Configurations; Advanced Ecc Memory Configuration; Online Spare Memory Configuration; General Dimm Slot Population Guidelines - HP APOLLO 2000 User Manual

For more information about product features, specifications, options, configurations, and compatibility, see the
product QuickSpecs on the Hewlett Packard Enterprise website.

Memory configurations

To optimize node availability, the node supports the following AMP modes:
• Advanced ECC—Provides up to 4-bit error correction and enhanced performance over Lockstep mode.
This mode is the default option for this node.
• Online spare memory—Provides protection against failing or degraded DIMMs. Certain memory is
reserved as spare, and automatic failover to spare memory occurs when the system detects a DIMM that
is degrading. This allows DIMMs that have a higher probability of receiving an uncorrectable memory error
(which would result in system downtime) to be removed from operation.
Advanced Memory Protection options are configured in the BIOS/Platform Configuration (RBSU). If the
requested AMP mode is not supported by the installed DIMM configuration, the node boots in Advanced ECC
mode. For more information, see the HPE UEFI System Utilities User Guide for ProLiant Gen9 Servers on the
Hewlett Packard Enterprise website.

Advanced ECC memory configuration

Advanced ECC memory is the default memory protection mode for this node . Standard ECC can correct
single-bit memory errors and detect multi-bit memory errors. When multi-bit errors are detected using
Standard ECC, the error is signaled to the node and causes the node to halt.
Advanced ECC protects the node against some multi-bit memory errors. Advanced ECC can correct both
single-bit memory errors and 4-bit memory errors if all failed bits are on the same DRAM device on the DIMM.
Advanced ECC provides additional protection over Standard ECC because it is possible to correct certain
memory errors that would otherwise be uncorrected and result in a node failure. Using HPE Advanced
Memory Error Detection technology, the node provides notification when a DIMM is degrading and has a
higher probability of uncorrectable memory error.

Online Spare memory configuration

Online spare memory provides protection against degraded DIMM s by reducing the likelihood of uncorrected
memory errors. This protection is available without any operating system support.
Online spare memory protection dedicates one rank of each memory channel for use as spare memory. The
remaining ranks are available for OS and application use. If correctable memory errors occur at a rate higher
than a specific threshold on any of the non-spare ranks, the node automatically copies the memory contents
of the degraded rank to the online spare rank. The node then deactivates the failing rank and automatically
switches over to the online spare rank.

General DIMM slot population guidelines

Observe the following guidelines for all AMP modes:
• Install DIMMs only if the corresponding processor is installed.
• When two processors are installed, balance the DIMMs across the two processors.
• White DIMM slots denote the first slot of a channel (Ch 1-A, Ch 2-B, Ch 3-C, Ch 4-D)
• Do not mix RDIMMs and LRDIMMs.
• When one processor is installed, install DIMMs in sequential alphabetic order: A, B, C, D, E, F, and so
forth.
• When two processors are installed, install the DIMMs in sequential alphabetic order balanced between the
two processors: P1-A, P2-A, P1-B, P2-B, P1-C, P2-C, and so forth.
• When single-rank, dual-rank, and quad-rank DIMMs are populated for two DIMMs per channel or three
DIMMs per channel, always populate the higher number rank DIMM first (starting from the farthest slot).
For example, first quad-rank DIMM, then dual-rank DIMM, and then lastly single-rank DIMM.
Memory configurations 89