HP ProLiant DL380 Gen9, User Manual

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Hardware options installation 66
Qualified memory is performance-tuned for ProLiant and BladeSystem servers and provides future
enhanced support through Active Health and manageability software.
Persistent memory combines the performance of memory with the persistence of traditional storage.
NVDIMMs are DIMMs that provide persistent memory and install in standard DIMM slots.
NVDIMM-Ns are NVDIMMs that combine DRAM with NAND flash memory, backing up the DRAM
contents to flash memory on power loss and restoring from NAND flash memory to DRAM on power on.
NVDIMM-Ns provide applications with the full performance capability of DRAM. NVDIMM-Ns are
supported in select HPE servers, drawing power from the HPE Smart Storage Battery to perform the
backup. The HPE 8GB NVDIMM is an NVDIMM-N.
For more information about NVDIMM-Ns and persistent memory, see the
HPE 8GB NVDIMM User Guide
on the Hewlett Packard Enterprise Information Library ( http://www.hpe.com/info/NVDIMM-docs ).
Operation stages for NVDIMM-Ns
•
While the server is powered on:
o
Each NVDIMM-N operates at the speed of a regular DDR4 DIMM and data is stored in the
DRAM.
o
Each NVDIMM-N accesses data in the DRAM based on the processor load/store instructions
and PCIe memory read and write transactions.
o
Each NVDIMM-N is accessed using special device drivers.
o
Each NVDIMM-N is not presented as regular system memory.
•
When power to the server is lost:
o
Each NVDIMM-N copies or backs up data from its DRAM to its NAND flash memory.
o
Each NVDIMM-N draws power from the HPE Smart Storage Battery on the server.
•
While the server is powered off, data is saved in the NAND flash memory of each NVDIMM-N.
•
When the server is powered on, each NVDIMM-N restores data from its NAND flash memory to its
DRAM during the server POST process.
For more information on persistent memory, see the Hewlett Packard Enterprise website
( http://www.hpe.com/info/persistentmemory ). For more information about HPE NVDIMMs, see the
product QuickSpecs on the Hewlett Packard Enterprise website (
http://www.hpe.com/info/qs
).
Memory subsystem architecture
The memory subsystem in this server is divided into channels. Each processor supports four channels,
and each channel supports three DIMM slots, as shown in the following table.
Channel Population order Slot number
1
A
E
I
12
11
10
2
B
F
J
9
8
7
3
C
G
K
1
2
3
4
D
H
L
4
5
6
For the location of the slot numbers, see "DIMM slot locations (on page 18 )."