Intel MFS5520VI User Manual

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Intel® Compute Module MFS5520VI TPS  
Functional Architecture 
Revision 1.3 
 
13 
Intel order number: E64311-005 
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The compute module Quick Reference Label DIMM slot identifiers provide information 
about the channel, and therefore the processor to which they belong. For example, 
DIMM_A1 is the first slot on Channel A on processor 1; DIMM_D1 is the first DIMM 
socket on Channel D on processor 2. 
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The memory slots associated with a given processor are unavailable if the given 
processor socket is not populated. 
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A processor may be installed without populating the associated memory slots provided a 
second processor is installed with associated memory. In this case, the memory is 
shared by the processors. However, the platform suffers performance degradation and 
latency due to the remote memory. 
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Processor sockets are self-contained and autonomous. However, all memory subsystem 
support (that is, Memory RAS, Error Management, and so on) in the BIOS setup are 
applied commonly across processor sockets. 
3.2.4 
Memory RAS 
3.2.4.1 
RAS Features 
The Compute Module supports the following memory RAS features: 
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Channel Independent Mode 
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Channel Mirroring Mode 
The memory RAS offered by the Intel
®
 Xeon
®
 Processor 5500 series and Intel
®
 Xeon
®
 
Processor 5600 series processors is done at channel level, that is, during mirroring, channel B 
mirrors channel A. All DIMM matching requirements are on a slot to slot basis on adjacent 
channels. For example, to enable mirroring, corresponding slots on channel A and channel B 
must have DIMMs of identical parameters. 
If one socket fails the population requirements for RAS, the BIOS sets all six channels to the 
Channel Independent mode. 
The memory slots of DDR3 channels from the Intel
®
 Xeon
®
 Processor 5500 series and Intel
®
 
Xeon
®
 Processor 5600 series processors should be populated on a farthest first fashion. This 
holds true even in the Channel Independent mode. This means that A2 cannot be 
populated/used if A1 is empty. 
3.2.4.2 
Channel Independent Mode 
In the Channel Independent mode, multiple channels can be populated in any order (for 
example, channels B and C can be populated while channel A is empty). Therefore, all DIMMs 
are enabled and utilized in the Channel Independent mode.  
3.2.4.3 
Channel Mirroring Mode 
The Intel
®
 Xeon
®
 Processor 5500 series and Intel
®
 Xeon
®
 Processor 5600 series support 
channel mirroring to configure available channels of DDR3 DIMMs in the mirrored configuration. 
The mirrored configuration is a redundant image of the memory, and can continue to operate 
despite the presence of sporadic uncorrectable errors. 
Channel mirroring is a RAS feature in which two identical images of memory data are 
maintained, thus providing maximum redundancy. On the Intel
®
 Xeon
®
 Processor 5500 series 
and Intel
®
 Xeon
®
 Processor 5600 series processors based Intel
®
 server boards, mirroring is