Seagate ST9500621SS ユーザーズマニュアル
Constellation.2 SAS Product Manual, Rev. H
11
5.0
Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of Con-
stellation.2 drives.
stellation.2 drives.
5.1
Internal drive characteristics
ST91000640SS
ST9500620SS
ST91000641SS
ST9500621SS
ST91000642SS
ST9500622SS
Drive capacity
1000
500
Gbytes (formatted, rounded off value)
Read/write data heads
8
4
Bytes per track
732,998
732,998
Bytes (average, rounded off values)
Bytes per surface
125,069
125,069
MB (unformatted, rounded off value)
Tracks per surface (total)
165,800
165,800
Tracks (user accessible)
Tracks per inch
270,000
270,000
TPI (average)
Peak bits per inch
1,544,000
1,544,000
BPI
Areal density
417
417
Gb/in
2
Internal data rate
84 - 163
84 - 163
MB/s (variable with zone)
Disk rotation speed
7200
7200
rpm
Avg rotational latency
4.16
4.16
ms
5.2
Seek performance characteristics
and
the
SAS Interface Manual
(part number
100293071) for additional timing details.
5.2.1
Access time
Including controller overhead
2
1
1.
Execution time measured from receipt of the Command to the Response.
,
(ms)
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.
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.
Access to data = access time + latency time.
7.7
8.7
7.5
8.5
Single track
Typical
3,4
0.23
0.44
0.23
0.44
Full stroke
Typical
3,4
17.26
18.28
17.06
18.08
2.
Assumes no errors and no sector has been relocated.
Not including controller overhead
1, 2
(ms)
Read
Write
Read
Write