AMD ATHLON 64 - Manual (Page 33)

Chapter 3 Analysis and Recommendations 33
Performance Guidelines for AMD Athlon™ 64 and AMD Opteron™
ccNUMA Multiprocessor Systems
40555 Rev. 3.00 June 2006
Figure 13. Both Write-Only Threads Running on Node 0 (Different Cores) under
Medium Background Load (High Subscription)
Figure 14. Both Write-Only Threads Running on Node 0 (Different Cores) under High
Background Load (High Subscription)
As shown in Figure 15 below, the advantage disappears at very high loads and the 0 hop-1 hop case
becomes slower than the 0 hop-0 hop case.
Medium: Total Time for both threads (write-write)
146%
129% 129%
139%
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
0.0.w.0 0.1.w.0 (0 Hops) (0 Hops)
0.0.w.0 0.1.w.1 (0 Hops) (1 Hops)
0.0.w.0 0.1.w.2 (0 Hops) (1 Hops)
0.0.w.0 0.1.w.3 (0 Hops) (2 Hops)
0 Hop
0 Hop 0 Hop
1 Hop 0 Hop
1 Hop 0 Hop
2 Hop
High: Total Time for both threads (write-write)
146%
136% 135%
146%
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
0.0.w.0 0.1.w.0 (0 Hops) (0 Hops)
0.0.w.0 0.1.w.1 (0 Hops) (1 Hops)
0.0.w.0 0.1.w.2 (0 Hops) (1 Hops)
0.0.w.0 0.1.w.3 (0 Hops) (2 Hops)
0 Hop
0 Hop 0 Hop
1 Hop 0 Hop
1 Hop 0 Hop
2 Hop