AMD athlon 64 User Manual

Page of 48
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