Datasheet

LLC Coherence Engine (Cbox) and Caching Agent (Sbox)
22 Datasheet Volume 2 of 2
4.1.1 LLC Major Features
•Cache size:
— 30 MB for ten Intel Xeon Processor E7-8800/4800/2800 Product Families
core topologies
• Organization:
— Associativity: 24 ways
— Line Size: 64 Bytes
•Protection:
— DECTED ECC for the data array
— SECDED ECC correct for the tag array
— SECDED ECC protection for the core valid array
— SECDED ECC protection for the LRU array
4.2 RTID Generation
The Cboxes associated with one Sbox have either 16, 24, 32, 48 or 64 RTIDs to divide
among themselves for HOM requests. In order to do this, each Cbox will have a
particular length for all freelists, and one base RTID to add to the priority-encoded
value from the selected freelist. Depending on the configuration (10 LLC, 8 LLC, 6 LLC,
or 4 LLC cache slices), Table 4- 1, Ta b le 4- 2 , and Tabl e 4 - 3 specify how the freelist
lengths and base RTIDs are programmed for the 5, 4, 3, or 2 Cboxes associated with
each Sbox respectively.
Table 4-1. RTID Generation 10 LLC (Last Level Cache) Slices
Sbox RTIDs Freelist Lengths Base RTIDs
16 4, 3, 3, 3, 3 0, 4, 7, 10, 13
24 6, 6, 4, 4, 4 or
5, 5, 5,5, 4
0, 6, 12, 16, 20
32 7, 7, 6, 6, 6, 0, 7, 14, 20, 26
48 10, 10, 10, 9, 9 0, 10, 20, 30, 39
64 12, 12, 12, 12, 12 0, 12, 24, 36, 48
Table 4-2. RTID Generation 8 LLC (Last Level Cache) Slices
Sbox RTIDs Freelist Lengths Base RTIDs
16 4, 4, 4, 4 0, 4, 8, 12
24 6, 6, 6, 6 0, 6, 12, 18
32 8, 8, 8, 8 0, 8, 16, 24
48 12, 12, 12, 12 0, 12, 24, 36
64 12, 12, 12, 12 0, 12, 24, 36