Tim:
I have a seagate drive that falls asleep when it gets bored. Sometimes it's quick to wake up (a few seconds), other times it takes ages (minutes), or may not wake up. I'm wondering if it has three different sleep levels.
Hiisi:
Well, yes. Fortunately you can configure sleep time-out using hdparm or even turn off power management completely. See man hdparm. I also find wikipedia page on hdparm very useful. Here it is: http://en.wikipedia.org/wiki/Hdparm
Unfortunately, that doesn't seem to work with one of my firewire connected drives.
# /sbin/hdparm -B255 /dev/sdd
/dev/sdd: setting Advanced Power Management level to disabled HDIO_DRIVE_CMD failed: Invalid argument
I'd already used hdparm, years ago, to save my laptop's internal drive from an early death.
And, smartctl can't be used with either of the USB or firewire external drives that I have (to check on them). The interface to the drive is too dumb, or the program isn't programmed to work through those interfaces.
I also find I'm getting errors. The drive can be heard clacking away *trying* to read, some files sometimes. And I'm also wondering whether it falls asleep before any drive changes get committed.
If in doubt use sync ;- )
Well, the trouble is the drive falling asleep at some time that you didn't notice... ;-) But since the dozing is some time after the last access, you'd expect that the file system changes would have been committed before the drive went to sleep.
I'm beginning to have suspicions that suspending the laptop is part of the equation.