[mythtv] Storage Groups - OK to move files between directories in same group ?

[Denys Dmytriyenko]

On Mon, Mar 17, 2008 at 03:19:27PM +0000, Albert Graham wrote:
> Dave,
> 
> Well, you're right, I'm also trying to keep the machine as cool as 
> possible when there is no need for it to be hot, just because drives are 
> spinning, the drive temps run about 55C which is close to the spec of 
> 60C, this is because they are packed so close to each other, also, when 
> I umount and  spin these drives down  (e.g. sdparm -C stop /dev/sdb), 
> the machine is almost silent, two small fans behind the drive enclosures 
> (controlled by sensors) spin down to silent mode and the drive temps 
> drop to about 25C
> (when spun down).
> 
> The QX9650 Quad Core runs at 19c when myth backend is recording 
> (@33Ghz), and 25c (@4Ghz)
> 
> I do have a separate frontend (laptop sitting on top of my Sky box (UK).
> 
> You can also see I've got a mega fan which runs about 600rpm (and is 
> practically silent - speed is controller manually from the front (below 
> the water tank). This fan is absolutely amazing.

Quite impressive. I have something similar though, with more, but smaller 
disks. I set them up to automatically go into standby (spin down) after a 
period of inactivity (say, 30 minutes) - "hdparm -S 241 /dev/sda". They are 
still mounted and when something accesses them (recording starts, or frontend
starts streaming), they are spun up again. The only difference is I don't have 
RAID on them. If you do hardware RAID (even fake-raid), the whole array is 
presented as a single /dev/sd? device and you cannot spin it down. Not sure if 
you can spin down individual /dev/sd? drives under a software /dev/md? RAID...

BTW, checked your pictures and noticed you use 5-in-3 enclosures, like ICY 
DOCK. I also started with them, but then found out they don't provide adequate 
cooling and drives make vibrating noices from time to time, as rails are all 
metal. So I replaced them with custom made 5-in-3 brackets with big 120mm fans 
in front of them. That keeps drives temperature around 40C.

Regards,
Denys