Online Spare Memory - NEC Express5800 120Rj-2 User Manual

User Guide

Online Spare Memory

The online memory spare feature puts a group of memory devices within a memory
branch into standby status as spare devices. If an unrecoverable error occurs in a
DIMM of the running group, the feature automatically changes the running DIMM
from the failed one to a DIMM in the standby group to continue the processing.
E
F
devices as those with capacities less than the actual physical
capacities. (The recognized capacities vary depending on the
number of DIMMs and the physical capacity per DIMM.)
The online spare memory feature can be used under the following conditions:
■ Install memory devices to more than one group in each memory branch. The server
can operate even if the memory branches are different in the number of DIMMs.
For example, no error occurs if memory branches 0 and 1 include four DIMMs (or
two groups) and six DIMMs (or three groups), respectively.
C
#1
#3
#5
Figure 117: Online Spare Memory
A: Motherboard
B: Memory Controller
C: Branch #0
D: Branch #1
E: In Operation
F: Standbys
Note: The operating system recognizes the memory
A
B
D
#2
#4
#6
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