when do files get saved on array when using cache?

[Tracenji]

Unraid 6.12.4

 

hello, just set up a new unraid server with a cache drive today, my cache device has 26GB used but my array only has 12MB

so when does the data on the cache get copied to the array?

 

i would assume a cache would work in the way that when writing to server it first gets written to cache and then basically immediately gets copied to the array drives while still remaining in cache

and then when reading an uncached file i would assume it would copy it to the cache drive and still keep a copy on the array

 

is there a way to have this behavior? ^^^

 

have it set it up wrong?

Edited November 5, 2023 by Tracenji
added unraid version

[JorgeB]

47 minutes ago, Tracenji said:

so when does the data on the cache get copied to the array?

You can run the mover manually or on a schedule to move the files, shares(s) also need to be correctly configured, see the GUI help.

[itimpi]

This is not how the Unraid cache feature works!   The purpose of the cache facility on Unraid is to provide a faster perceived write speed when writing to User Shares than happens if you write directly to the parity protected array.

 

Under Unraid if you have a User Share set up to use a pool for caching purposes, then this is where and new file gets written (space permitting).  It later gets moved across to the main array (as long as you have this specified as secondary storage) when mover runs (default is scheduled for overnight).   The file only ever exists EITHER on cache OR on array - never on both.