Memory Bandwidth - IBM Power 595 Technical Overview And Introduction

Figure 2-32 Memory system logical view
Each processor book supports a total of eight memory units (32 DIMMS or eight memory
features). A fully configured Power 595 server with eight processor books supports up to 64
memory units (256 DIMMs). Using memory features that are based on 64 GB DIMMs, the
resulting maximum memory configuration is four TB.
Note: One memory unit is equal to an orderable memory feature. One memory unit
contains four memory DIMMs.

2.7.1 Memory bandwidth

The Power 595 memory subsystem consists of L1, L2, and L3 caches along with the main
memory. The bandwidths for these memory components is shown in Table 2-14
Table 2-14 Memory bandwidth
Description
L1 (data)
L2
L3
Main memory
Bus size
2 x 8 bytes
2 x 32 bytes
4 x 8 bytes
4 x 1 byte (write)
4 x 2 bytes (read)
Chapter 2. Architectural and technical overview
Bandwidth
80 GBps
160 GBps
80 GBps (per 2-core MCM)
2.56 TBps (per 64-core system)
42.7 GBps (per 2-core MCM)
1.33 TBps (per 64-core system)
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