My array has 3 disks, all Seagate ST5000LM000

I have telegraf polling SMART data with a poll interval of 10 seconds.

 

I noticed a chirping every 10 or so seconds coincident with drives' access LEDs flashing.

I figured the access was due to telegraf and the chirping was the heads parking/un-parking.

 

The SMART reports seem to confirm this, e.g.

9 Power on hours 0x0032 094 094 000 Old age Always Never 5996 (173 29 0)
193 Load cycle count 0x0032 001 001 000 Old age Always Never 454511

That works out to 75 times/hour so it's probably been going on ever since I installed telegaf.

 

I disabled head parking on all 3 drives with smartctl:

smartctl -s apm,off /dev/sdX

which stopped the chirping but I still see the drives' LEDs flash every 10 seconds.

 

What's confusing is I have another 3 drives in a pool (on 6.9.0-RC1), all WDC WD3200BEKX

 

These drives are also polled by telegraf with no excessive head parking, which can be explained by the drives' internal settings:

9 Power on hours 0x0032 033 033 000 Old age Always Never 48920 (5y, 6m, 27d, 8h)
193 Load cycle count 0x0032 200 200 000 Old age Always Never 647

but also no LED flashing, which I can't explain.

 

One seagate and one WD are on the motherboard's controller and the rest on the HBA so it's not likely a controller issue.

 

Questions

1. Would it be wise to disable APM on the Seagates on startup using smartctl?
2. Is the difference in LED behavior likely drive-specific or due to the way unRAID treats array disks vs pool disks?

 

1 hour ago, CS01-HS said:

Would it be wise to disable APM on the Seagates on startup using smartctl?

Yes, you can have a script doing that after every reboot.

 

1 hour ago, CS01-HS said:

drive-specific

This, 2.5" drives are usually much more aggressive with power saving features, WD black are usually a exception since they are optimized for performance.

58 minutes ago, JorgeB said:

Yes, you can have a script doing that after every reboot.

Great, added to config/go. Easy fix, thanks.

 

58 minutes ago, JorgeB said:

This, 2.5" drives are usually much more aggressive with power saving features, WD black are usually a exception since they are optimized for performance.

The LED difference is still curious. I always assumed the "access" signal was caught when the MB (or card) detected HD access but this suggests it relies on the drive to say "I have been accessed."

 

 

On 12/15/2020 at 1:55 PM, CS01-HS said:

 

smartctl -s apm,off /dev/sdX

after this, is the driver still able to go into standby?

 

 

I think so but I'm running RC1 and telegraf and that combination prevents spindown. hdparm -y works for a time.