I have seen a lot of issues recently where cache drives are getting filled up causing issues(Not me, but posts).  Would a warning of some kind before allowing this to be set be helpful?

 

Also, what are some of the use-cases for this setting?

appdata, domains, system shares are cache-prefer by default. This setting is similar to cache-only, but it allows overflow to the array. The point being to keep the files on cache for better performance. And to allow array to spin down, since those shares always have open files when dockers or VMs are enabled.

 

I see these sorts of problems all the time because users don't understand this setting. The webUI has been enhanced with more obvious and complete descriptions of what these do, but nobody bothers to read it seems.

 

There is no single word that adequately explains cache-yes and cache-prefer. Maybe a different word besides prefer would lead to less misunderstanding, but I don't know what that word is. Maybe a warning would make them take the trouble to understand, but often even if they do read they still don't understand.

 

13 minutes ago, hugenbdd said:

what are some of the use-cases for this setting?

Also see this FAQ:

 

Also, since mover can't move open files, appdata, domains, system shares that overflow can't be moved back to cache without disabling Docker and VM Manager, so even allowing overflow for these can lead to problems, though things will continue to work so not as bad as failed writes I guess.

There is also the fact that the "prefer" setting works even if you do not yet have a cache drive and then later when one is added content gets moved to the cache without further user action.   

 

However it does cause a problem if a cache temporarily disappears for some reason as then you can end up with duplicates of files in the system share such as the docker image.  Not sure I can see how this could be avoided though.

 

41 minutes ago, trurl said:

appdata, domains, system shares are cache-prefer by default. This setting is similar to cache-only, but it allows overflow to the array. The point being to keep the files on cache for better performance. And to allow array to spin down, since those shares always have open files when dockers or VMs are enabled.

 

I see these sorts of problems all the time because users don't understand this setting. The webUI has been enhanced with more obvious and complete descriptions of what these do, but nobody bothers to read it seems.

 

There is no single word that adequately explains cache-yes and cache-prefer. Maybe a different word besides prefer would lead to less misunderstanding, but I don't know what that word is. Maybe a warning would make them take the trouble to understand, but often even if they do read they still don't understand.

 

Also see this FAQ:

 

Thank you!

I have mine set to cache-yes as I have a very large cache drive so didn't think of these.

7 minutes ago, hugenbdd said:

Thank you!

I have mine set to cache-yes as I have a very large cache drive so didn't think of these.

Using the Yes setting means that you only want the files temporarily on the cache - but want them to end up on the array.   Is this what you really want with a large cache drive?    if you want the final residing place to be the cache then you use Prefer.
 

The ‘yes’ setting is often misinterpreted but it is a hang-over from the fact that originally only the Yes and No settings existed.    I think if we were starting with a clean sheet we would probably invert the meaning of the Yes and Prefer setting but at this point it is probably not practical as it would cause too much disruption.

1 minute ago, itimpi said:

Using the Yes setting means that you only want the files temporarily on the cache - but want them to end up on the array.   Is this what you really want with a large cache drive?    if you want the final residing place to be the cache then you use Prefer.
 

The ‘yes’ setting is often misinterpreted but it is a hang-over from the fact that originally only the Yes and No settings existed.    I think if we were starting with a clean sheet we would probably invert the meaning of the Yes and Prefer setting but at this point it is probably not practical as it would cause too much disruption.

My Bad... set to Only... 

Maybe radio buttons for this with a full description for each and don't even display the single word, just keep it internally.