Seagate ST4000NM0043 ユーザーズマニュアル

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Constellation ES Series SAS Product Manual, Rev. F
5.0
Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of Con-
stellation ES drives.
5.1
Internal drive characteristics
ST32000444SS
ST31000424SS
ST3500414SS
 
ST32000445SS
ST31000425SS
ST3500415SS
 
ST32000446SS
ST31000426SS
ST3500416SS
Drive capacity
2000
1000
500
GB (formatted, rounded off value)
Read/write data heads
8
4
2
Bytes per track
1,012,608
1,012,608
1,012,608
Bytes (average, rounded off values)
Bytes per surface
250,000
250,000
250,000
MB (unformatted, rounded off value)
Tracks per surface (total)
248,600
248,600
248,600
Tracks (user accessible)
Tracks per inch
237,000
237,000
237,000
TPI (average)
Peak bits per inch
1,515,000
1,515,000
1,515,000
BPI
 
Areal density
347
347
347
Gb/in
2
Internal data rate
95 - 212
95 - 212
95 - 212
MB/s (variable with zone)
Disc rotation speed
7200
7200
7200
rpm
Avg rotational latency
4.16
4.16
4.16
ms
5.2
Seek performance characteristics
See Section 12.4.1, "SAS physical interface" on page 64  and  the  SAS Interface Manual (part number 
100293071) for additional timing details.
5.2.1
Access time 
Not including controller overhead
2
 (ms)
1
1.
Execution time measured from receipt of the Command to the Response.
Average
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.
,
4.
Access time = controller overhead + average seek time and applies to all data transfer commands.
 
Access to data = access time + latency time.
8.3
9.3
8.5
9.5
Single track
Typical
3,4
0.5
0.8
0.7
1.0
Full stroke
Typical
3,4
18
19
18.2
19.2
2.
Assumes no errors and no sector has been relocated.
Including controller overhead
1, 2
 (ms)
Read
Write
Read
Write