Seagate ST9100828SB Server User Manual


 
Momentus 5400.3 SATA Blade Server Product Manual, Rev. E
7
2.7 Seek time
Seek measurements are taken with nominal power at 25°C ambient temperature. All times are measured using
drive diagnostics. The specifications in the table below are defined as follows:
Track-to-track seek time is an average of all possible single-track seeks in both directions.
Average seek time is a true statistical random average of at least 5,000 measurements of seeks between
random tracks, less overhead.
Note. These drives are designed to consistently meet the seek times represented in this manual. Physical
seeks, regardless of mode (such as track-to-track and average), are expected to meet the noted
values. However, due to the manner in which these drives are formatted, benchmark tests that
include command overhead or measure logical seeks may produce results that vary from these
specifications.
2.8 Time to ready
2.9 Power specifications
The drive receives DC power (+5V) through a native SATA power connector.
2.9.1 Power consumption
Power requirements for the drives are listed in the table on page 7. Typical power measurements are based on
an average of drives tested, under nominal conditions, at 25°C ambient temperature, after 25 minutes of oper-
ation.
Spinup power
Spinup power is measured from the time of power-on to the time that the drive spindle reaches operating speed.
Seek mode
During seek mode, the read/write actuator arm moves toward a specific position on the disc surface and does
not execute a read or write operation. Servo electronics are active. Seek mode power is measured based on
three random seek operations every 100 msecs. This mode is not typical.
Read/write power and current
Read/write power is measured with the heads on track, based on three 63 sector read or write operations
every 100 msecs.
Table 2: Typical seek times
Typical seek times (msec) Read Write
Track-to-track 1.0 1.5
Average 11.0 13.0
Full-stroke 22.0 24.0
Average latency 5.56 5.56
Time to ready Typical
Max @ 25°C
Power-on to Ready (sec) 3.5 8.0
Standby to Ready (sec) 3.0 8.0