Seagate ST9900705SS 用户手册
Savvio 10K.5 SAS Product Manual, Rev. D
9
5.0
Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of Sav-
vio drives.
vio drives.
5.1
Internal drive characteristics
ST9900805SS ST9600205SS
ST9450405SS ST9300605SS
ST9900705SS ST9600105SS
ST9450305SS ST9300505SS
ST9900605SS ST9600005SS
ST9450205SS ST9300405SS
Drive capacity
900
600
450
300
GB
(formatted, rounded off value)
Read/write data heads
6
4
3
2
Bytes per track
821.4
821.4
821.4
821.4
KBytes
(avg, rounded off values)
Bytes per surface
151,800
151,800
151,800
151,800
MB
(unformatted, rounded off value
)
Tracks per surface (total)
184,799
184,799
184,799
184,799
Tracks
(user accessible)
Tracks per inch
300
300
300
300
KTPI
(average)
Peak bits per inch
1686
1686
1686
1686
kBPI
Areal density
506
506
506
506
Gb/in
2
Disc rotation speed
10K
10K
10K
10K
rpm
Avg rotational latency
3.0
3.0
3.0
3.0
ms
5.2
Seek performance characteristics
See Section 12.4.1, "SAS physical interface" on page 67 and the SAS Interface Manual (part number
100293071) for additional timing details.
100293071) for additional timing details.
5.2.1
Access time
Including controller overhead
2
(ms)
1
1.
Execution time measured from receipt of the Command to the Response.
,
Average
900GB models
Typical
3,4
3.9
4.3
3.7
4.1
Single track
0.4
0.6
0.2
0.4
Full stroke
7.9
8.3
7.7
8.1
Average
600, 450, 300GB
models
Typical
4
3
3.
Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as
measured on a representative sample of drives.
measured on a representative sample of drives.
,
4.
Access time = controller overhead + average seek time and applies to all data transfer commands.
Access to data = access time + latency time.
3.6
4.0
3.4
3.8
Single track
0.4
0.6
0.2
0.4
Full stroke
7.3
7.6
7.1
7.4
2.
Assumes no errors and no sector has been relocated.
Not including controller overhead
1,2
(ms)
Read
Write
Read
Write