IBM DTNA-22160 - Travelstar 2.1 GB Hard Drive, Specifications

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The seek time is measured from the start of motion of the actuator to the start of a reliable read or write
operation. Reliable read or write implies that error correction/recovery is not employed to correct for arrival
problems. The Average Seek Time is measured as the weighted average of all possible seek combinations.
m a x
S U M ( m a x + 1
Ä
n ) ( T n . i n + T n . o u t )
n = 1
W e i g h t e d A v e r a g e =
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
( m a x + 1 ) ( m a x )
W h e r e :
m a x = M a x i m u m S e e k L e n g t h
n = S e e k L e n g t h ( 1 t o m a x )
T n . i n = I n w a r d m e a s u r e d s e e k t i m e f o r a n t r a c k s e e k
T n . o u t = O u t w a r d m e a s u r e d s e e k t i m e f o r a n t r a c k s e e k
3.3.3 Single Track Seek Time
Figure 7. Single Track Seek Time
Single track seek is measured as the average of one (1) single track seek from every track in both directions
(inward and outward).
Function Typical Max
R E A D 4 msec 5.5 msec
Write 4 msec 6.5 msec
Drive Characteristics
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