SOLVED Help with cache disk - fine tuning

[flying_rabbi]

Brains trust, this has been something Ive wanted to achieve since I discovered the cache disk many moons ago, and I'm not sure if I'm not setting it up correctly, or if its something Unraid doesn't currently support.

 

Amongst other things, I have a 40TB Media Share, with a 2TB NVME drive set up as a cache drive on my system.

 

What i want, is when a file is put on the array, or a file is read from the array, it is then copied over to the cache disk, thereby not needing to spin up the array next time it get accessed, and it is a mirror of the file on the array, ensuing backup.

 

When the cache disk gets full, i want it to overwrite the older files from that share off the cache disk. I've had a pretty deep dive into the cache options, and squid's CA Mover Tuning plugin with no avail.

 

The premise of this is that with my media files, it seems that there is only ever a very small portion that gets used on a regular basis, eg a TV Show thats being binged, the new movies being downloaded etc. When i tell my cache drive to "prefer cache" for my media share, it just hoovers up the first portion of the share, which is completely useless.

 

Brains trust, I bow to you wisdom! is there any way to achieve this? Or is this a feature request?

 

Cheers!

 

 

Edited April 21, 2021 by flying_rabbi

[itimpi]

There is no functionality of the type you describe in unRaid.    A file is only ever meant to exist in one place - either on the array or on a pool (cache).

[flying_rabbi]

2 hours ago, itimpi said:

There is no functionality of the type you describe in unRaid.    A file is only ever meant to exist in one place - either on the array of on a pool (cache).

Bugger. Many thanks, at least now i know, and can start at least thinking about it differently.

[itimpi]

1 hour ago, flying_rabbi said:

Bugger. Many thanks, at least now i know, and can start at least thinking about it differently.

 

There have been those who have tried to develop user scripts to have functionality along these lines.   They try to exploit the fact if you manually put the same file in more than one location then the copy that is shown under a User Share is the first that is found when searching the pools and then the array disks in order.  However these scripts then have to handle how to get the right files onto the pool (cache) and how to later handle backup onto the array.

[flying_rabbi]

fair enough.  I guess its all about "expectation management". I always thought that the cache drive was able to function as a mirror or sorts, with the mover doing some sort of "parity check" on a schedule.

 

In an ideal world, that's all i want my NVME drive to do, just act as fast storage for frequently used files. With so many edge cases, a developer cant keep everyone happy all the time, and i definitely respect that!.

 

Many thanks for your time!

Edited April 22, 2021 by flying_rabbi