Introduction
error is then reported so that preventative maintenance can be performed. As
long as there are enough good locations to allow the proper operation of the
server, no further action is taken other than recording the error in the error logs.
If the error is not recoverable, then Memory Scrubbing sends an error message
to the LED Diagnostic Path, which then turns on the proper lights and LEDs to
guide you to the damaged DIMM. If Memory Mirroring is enabled, then the
mirrored copy of the data in the damaged DIMM is used to refresh the new
DIMM once it is installed.
Redundant Bit Steering
This is the equivalent of a hot-spare drive in a RAID array. Redundant Bit
Steering is based in the memory controller, giving the server the ability to sense
when a chip on a DIMM has failed and route the data around the failed chip.
Redundant Bit Steering reassigns memory bits to new locations within memory
when recoverable errors have been detected. Once a recoverable error is found
by Memory Scrubbing, Redundant Bit Steering writes the data that was to be
stored in the damaged memory locations to spare memory locations within the
same DIMM.
Memory Scrubbing and Redundant Bit Steering work in conjunction with
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each other and do not require Memory Mirroring to be enabled to work
properly.
Memory Mirroring
Memory Mirroring allows you to improve the memory reliability of the server by
creating a mirror of the data in memory port one and storing it in memory port
two.
When Memory Mirroring is enabled in BIOS code, the data that is written to
memory is stored in two locations. One copy is kept in the memory port one
DIMMs, while a second copy is kept in the memory port two DIMMs. During the
execution of the read command, the data is read from the DIMM with the least
amount of reported memory errors through Memory Scrubbing, which is
enabled with Memory Mirroring.
For Memory Mirroring to work, you must have the same amount of
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memory in both memory ports.
U41621-J-Z156-1-76
Features
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