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I am able to set both APM and spindown times using the command:

hdparm -S 246 -B 128 /dev/sda

Unfortunately I can only find the APM value in the information output:

hdparm -I /dev/sda | grep Advanced

How can I see the spindown time value? I suspect my disc it is ignoring my value. I would like to see it. Tried smartctl but with no luck, help.

Update: It turned out tuned is very aggressive. When I turned it down, my discs does not spin down. It was setting something there.

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up vote 6 down vote accepted

There does not seem to be a way to query that value with hdparm, however you can see if the drive is in a standby or active state...

> sudo hdparm -C /dev/sdb

 drive state is:  standby

> sudo hdparm -C /dev/sda

 drive state is:  active/idle
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At least something, thanks. – lzap Aug 29 '11 at 7:06

The option -B 128 inhibits spindown, so your -S option is useless. Have a look at man hdparm. Spindown is only possible with -B parameters of 127 and less.

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Yes. But additionally on my Samsung drive "-B 127" did a spin down before the with -S configured time of 15 minutes. This means you might want to set it even higher to allow the spin down time setting to work. I also found this information here which suggest a setting of "-B 150" which works for me too. The disc will then spin down after the specified time. – Benjamin Peter Apr 15 at 19:16

The output from man hdparm includes the following:

-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 seconds 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.

Your setting of 246 would therefore mean 6 units of 30 minutes (3 hours), although I don't know how the value for -B is interpreted when -S is also specified.

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