-B Get/set Advanced Power Management feature, if the drive supports
it. A low value means aggressive power management and a high
value means better performance. Possible settings range from
values 1 through 127 (which permit spin-down), and values 128
through 254 (which do not permit spin-down). The highest degree
of power management is attained with a setting of 1, and the
highest I/O performance with a setting of 254. A value of 255
tells hdparm to disable Advanced Power Management altogether on
the drive (not all drives support disabling it, but most do).
-S Put the drive into idle (low-power) mode, and also set the
standby (spindown) timeout for the drive. This timeout value is
used by the drive to determine how long to wait (with no disk
activity) before turning off the spindle motor to save power.
Under such circumstances, the drive may take as long as 30 sec‐
onds to respond to a subsequent disk access, though most drives
are much quicker. The encoding of the timeout value is somewhat
peculiar. A value of zero means "timeouts are disabled": the
device will not automatically enter standby mode. Values from 1
to 240 specify multiples of 5 seconds, yielding timeouts from 5
seconds to 20 minutes. Values from 241 to 251 specify from 1 to
11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5
hours. A value of 252 signifies a timeout of 21 minutes. A
value of 253 sets a vendor-defined timeout period between 8 and
12 hours, and the value 254 is reserved. 255 is interpreted as
21 minutes plus 15 seconds. Note that some older drives may
have very different interpretations of these values.
您可以查看...中的
hdparm
命令terminal
特别是 -B 或 -S 选项...