Figure 6.2 shows the reduction in reposition events with speed matching enabled relative to
speed matching disabled. The statistics show that at each host data rate from 1-32 MB/sec,
Speed matching enabled reduces the number of reposition events. Data points from 33-40 were
removed for clarity. At speeds greater than 32 MB/sec, there is no difference between speed
matching enabled vs disabled. At those speeds, the drive is operating at its fastest possible speed
(same speed as speed matching disabled).
Figure 6.2: Speed Matching Comparison- Reposition Events
1946
948
615
448
349
282
234
198
171
149
131
116
103
92
82
77
126
120
113
106
98
92
84
77
71
63
55
48
41
34
27
19
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Host Data Rate MB/sec
0
50
100
150
200
250
Speed On
Constant
Speed Matching Comparison
Reposition Events
74
70
66
63
60
55
52
50
44
40
37
35
34
26
23
19
11
31
25
19
13
7
23
19
14
9
7
19
15
10
6
7
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Host Data Rate MB/sec
0
50
100
150
200
250
Speed On
Constant
Speed Matching Comparison
Reposition Events
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