Hi, I have a DELL T20 running 6.9.1 with 4 drives (plus a ssd for cache and 1 drive for parity).

 

I use it for a VM (home assistant OS) plus many dockers ( Plex, Radarr Sonarr Deluge etc, Nextcloud, UniFi controller, MQTT, Deconz etc)

 

I added a tasmota smart plug and noticed that consumption is always above 70w (even more when running parity check and other tasks).

 

I’m looking for advices to reduce idle and general power consumption.

 

I thought that running appdata on cache only would make some change but I didn’t see any significant difference.

 

Any other suggestions?

 

 

Thank you in advance!

Late to the reply, but don't visit this sub-forum often.

 

70W is a fairly low draw.  You didn't say what is going on at the time (drives spun up or not, activity, etc) so it is hard to gauge where to go from here.

 

As you have 5 spinning drives (4 + parity), the #1 controllable thing is to keep drives spun down as much as possible.  Each at idle is ~8W of power.

 

This is a challenge when running VMs and Dockers, as each of these seem to always want to access a disk for something.  Moving as much of their working files to cache/ssd as possible (and using cache for shares when possible).

 

You can play around, spinning up/down your drives from Main, and see if there are any saving to be found.  Turning off your VM/Dockers to see which is calling for power using functions.

 

The Tips and tweaks plugin also will allow you to change the CPU Scaling Governor, which may save you a watt or two, but suspect the only savings to be found will be in keeping drives spun down.

Quote

You didn't say what is going on at the time (drives spun up or not, activity, etc) so it is hard to gauge where to go from here.

How to check if drives are up or down? Ther's a page where i can see status?

 

In order to reduce HDD usage I moved the following shares to "Prefer : Cache"

 

1. Appdata
2. Docker
3. Domain
4. Download (used by deluge ...)
5. Isos
6. Nextcloud
7. System

But I cannot see any significative change.

 

Thank you for your support

Main tab.  Green dot is spun up, grey is spun down.  Spun up drive will also show the disk temp.

 

Click on the dot to spin up/down that disk.  Click on the arrows below, to spin all up/down.

 

Ok. I tested it.

But something weird is happening.

 

I spun down everything and of corse everything came on again.

 

So I shut down most of the dockers, all that use share on array. Drive are spin up the same. 

So I stopped ALL containers and VM (that should use appdata only) . Nothing changed. Drive become green again.

 

So I disable VM and Docker via settings. Drive becomes up again!

So I runned mover hoping to remove all traces of data in the array.

 

I don't know what else I can do....

 

 

Update.

 

I used OpenFiles and FileActivity to check if anything is used by anyone on my home but there's no evidence...

 

Second Update:

 

I found out syslog server was on and writing to a disk in the array. After disable I can now spin down drive (it seems). Power is now reduced by almost 10w. I have 4 drives + parity. It is a good result in your opinion?

Edited April 17, 20215 yr by Jokerigno

The simple way was use UD plugin, then setting all VM and docker use /mnt/disks/xxxxxx . My rotational disk 99% were spindown, this will save around 5w per each spinup disk.

 

 

 

Edited April 17, 20215 yr by Vr2Io

I noticed that consumption got reduced indeed. It depends on the activity but saving is from 10 to 20 W. Greta will be proud of me!

Good deal.  As I noted initially, there really isn't much room for savings when you are already at 70W.  And how much you can find really depends on your hardware (your drives look to be around 5W spinning and idle - my HGST are more power hungry, around 8W each).

Great result indeed!