Savvio 15K SAS Product Manual, Rev. B
4.0 Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of Sav-
vio drives.
4.1 Internal drive characteristics
ST973451SS ST936751SS
Drive capacity 73.4 36.7 Gbytes (formatted, rounded off value)
Read/write data heads 4 2
Tracks per surface (total) 42,554 42,554 Tracks (user accessible including spare tracks)
Tracks per inch 150 150 kTPI (average)
Peak bits per inch 861.81 861.81 kBPI
Areal density 130.58 130.58 Gbit/in
2
Internal data rate 957.51 to 1,282.08 957.51 to 1,282.08 Mbits/sec (variable with zone)
Disc rotation speed 15k 15k rpm
Avg rotational latency 2 2 msec
4.2 Seek performance characteristics
See Section 9.4.1, "SAS physical interface" on page 54 and the SAS Interface Manual (part number
100293071) for additional timing details.
4.2.1 Access time (Gen 2.0 LP data)
Not including controller overhead (msec)
Read Write
Average Typical
1
,
2
1. Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as
measured on a representative sample of drives.
2. Access to data = access time + latency time.
2.9 3.3
Single track Typical
1,2
0.2 0.4
Full stroke Typical
1,2
5.1 5.5
