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26 Datasheet Volume 2 of 2
5.1.1 The Tracker Modes
The tracker modes (0..3) are specifically chosen to support systems consisting of 4
gluelessly connected Intel Xeon Processor E7-8800/4800/2800 Product Families
sockets and 2, 4 IOH/XNC nodes (IOH = I/O Hub, XNC = eXternal Node Controller).
Minimal support is also provided for 8 IOH/XNCs. Mode 5 has been added to support
glueless 8 Intel Xeon Processor E7-8800/4800/2800 Product Families sockets and 4
IOH nodes. In general, 32 entries per IOH/XNC are supplied to mitigate bandwidth
restrictions for the long latency operations typically associated with these nodes
(except for the 8 IOH/XNCs configuration).
The supported tracker modes are listed in Tab l e 5 - 1 .
Note: Tracker Modes 6 and 7 are new, and Tracker Mode 4 has been updated for the Intel
Xeon Processor E7-8800/4800/2800 Product Families.
• Some NID bits have to be zero or one.
• XNC NID assignment follows IOH’s NID, with NID<4> set 1.
• * H corresponds to the co-located Sbox.
• In Hemisphere mode, nodeID<1> in the SAD target lists XORed with the
hemisphere number (0 or 1) and is normally zero.
• Changes to the tracker mode should only be made when the system is quiesced.
Table 5-1. Tracker Allocation Modes
Mode Purpose
Sboxes x #Entries,
NID Assignment
IOH/XNCs x #Entries, NID
Assignment
0 4S HemiSphere + 4 IOH/XNC 4 x 32, 0YZH1* 4 x 32, 0/1YZ00
1 4S HemiSphere + 2 IOH/XNC 4 x 48, 0YZH1 2 x 32, 0/10Z00
2 4S Non-HemiSphere + 2 IOH/XNC 8 x 24, 0YZH1 2 x 32, 00Z00
3 4S Non-HemiSphere + 4 IOH/XNC 8 x 16, 0YZH1 4 x 32, 0YZH1
4 8S HemiSphere + 4IOH/XNC 2X48+ 6X16,
XYZ01 -->Sbox0
XYZ11
4x16, 0XY00
5 8S HemiSphere + 4IOH/XNC 4x32+4x16, XYZH1 4x16, 0YZ00
6 4S Hemisphere + 2 IOH/XNC 1 X 64 + 3 X 32,
0XY01 -->Sbox0
0XY11 -->Sbox1
2 x 32,
0XY00 (XY cant be '11)
7 4S Non-Hemisphere + 2 IOH/XNC 2 X 32 + 6 X 16
0XY01 -->Sbox0
0XY11 -->Sbox1
2 x 32,
0XY00 (XY cant be '11)
Table 5-2. TID Assignment Restrictions (Sheet 1 of 2)
Mode Configuration Sboxes IOH/XNCs
0 4S HemiSphere + 4 IOH/XNC TID [0...31]
1 4S HemiSphere + 2 IOH/XNC TID [0...47] TID [0...31]
2 4S Non-HemiSphere + 2 IOH/XNC TID [0...23] TID [0...31]
3 4S Non-HemiSphere + 4 IOH/XNC TID [0...15] TID [0...31]
4 8S Hemisphere + 4 IOH/XNC [0…47], [0…15] TID [0...15]