I have been trying to isolate why my new array keeps getting accessed (meaning it never spins down).

 

I believe it's because the docker image is on the array and it keeps using it (every 10s or so) even if no plugins are running

 

Can anyone confirm this?

 

So, I believe I need a non-array disk for the docker image and perhaps the plugins config files, etc.

 

The question is can I do this by adding say a 64/128GB SSD as a cache drive even if the NAS is not kept on 24/7 (i.e. it's not left on over night normally)?

Or are there better ways to do this?

 

Anyone have any suggestions (for the record I have a three 2TB disk array and the OS is on a USB3.0 32GB).

 

Thanks is advance

 

Sorry to bump this so soon but I really wanted to place any hardware orders so they arrive before Easter.

 

Can anyone suggest the best way of handle docker without the continuous array accesses?

 

Thanks

The question is can I do this by adding say a 64/128GB SSD as a cache drive even if the NAS is not kept on 24/7 (i.e. it's not left on over night normally)?

Or are there better ways to do this?

 

I don't understand how shutting it down during the night would affect how the cache drive handle the data.

Personally, I use my docker on my cache drive which is a 240 GB SSD (XFS) and everything works fine.

I am also not sure why it would make much difference to array disks being spun up?  Assuming that docker is installed on a /mnt/disk?? type path then only that disk would be kept active by docker.  If the other disks are being let active then it is something else (although it may well be an app running under docker).

I used to have my Docker image on a traditional spinner cache drive, and it would definitely sleep most of the time.  However, I really only run one or two Dockers, and have a pretty good handle on the frequency of it trying to access any of my data.  If you're suggesting that having Docker enabled without a container being active is still accessing your disks every 10 seconds, one option would be to just disable Docker and see if that stops the issue.  Do you have cache_dirs installed?

 

As others have said, having Docker on an SSD cache drive should be more energy efficient than having your cache drive be a traditional spinner.  If your Docker image is currently on an array disk, it should really only spin up that particular disk and not your whole array when it's trying to read/write to the drive.  If your entire array is always spinning, that then makes it sound like you're sharing the entire /mnt folder and it's actively scanning them (or something similar), or whatever is in your Docker container is actively monitoring your folders?  Or you have the Docker mount on a user share that includes all your drives?

 

In any case, whether or not you keep your unRAID box on all night or not doesn't really have an effect on if you have an SSD cache.  Most people, however, leave their NAS on 24/7, especially if they have a good handle on keeping their disks spun down.  Ideally you should have your Docker image on the cache or a disk outside of the array.

I am finding that with the docker img on disk1 the parity disk and disk1 get accessed every 10s or so and never spin down (disk 2 does spin down).

 

This happens even if all the apps on the dock have all been stopped.

Just a quick update to say that with the SSD cache drive installed and the docker img ported to it the disks spin down as expected.

 

On the plus side writing in now a sustained 100Mb/s irrespective of the file size

 

Thanks

 

RJJ

Not sure if this is related, but i have my docker image on ssd cache, but the content still gets copied to main array (disk1). How do i make certain folders only stay in cache drive?

Not sure if this is related, but i have my docker image on ssd cache, but the content still gets copied to main array (disk1). How do i make certain folders only stay in cache drive?

Any top level folder on cache or the array is considered a user share. Mover will move any top level folder from cache to the array unless that user share is set to Use cache: Only.

 

Where is your docker.img?

For me, the docker.img is on the top level of the drive and I have set the AppData share (where the docker application's config files are) set as cache only.

This seems to keep the mover away from these files (you can see in the log that it ignored AppData).