DELL 2 x Intel Xeon E7-4860 338-BFMX User Manual

Datasheet Volume 2 of 2

21

The Intel Xeon Processor E7-8800/4800/2800 Product Families core to the last level 
cache (LLC) interface is managed by the LLC coherence engine (Cbox). All Intel Xeon 
Processor E7-8800/4800/2800 Product Families core to Intel

 

QuickPath Interconnect 

messages are handled through the Cbox and system interface logic. The Intel Xeon 
Processor E7-8800/4800/2800 Product Families contain ten instances of the Cbox, each 
managing 3 MB of the 30 MB LLC. Five instances of the Cbox, C0-C4, are associated 
with the Sbox 0, and C5-C9 are associated with Sbox 1. 

 provides a Intel Xeon Processor E7-8800/4800/2800 Product Families block 

diagram including Cbox and Sbox.

The 30 MB Last Level Cache (LLC) consists of ten 3 MB slices and are addressed via an 
address hash function. This function is designed to evenly distribute accesses among 
the cache slices, even if the access pattern is a regular stride. It is also designed to 
evenly distribute accesses among the sets (indexes) of each slice.

(LLC Coherence Engine)

(Router)

30M Last Level Cache (L3 Cache)

(Caching Agent 2)

(Home 

Agent 1)

(Home 

Agent 2)

(Memory 

Controller)

(Memory 

Controller)

(Physical 

Layer)

(Physical 

Layer)

(Caching Agent 1)

(Physical 

Layer)

(Physical 

Layer)

(Physical 

Layer)

(Physical 

Layer)

Dual Intel

®

SMI 

Channels

Dual Intel

®

SMI 

Channels

(Power Controller)

(System Config 

Controller)