Cache Drive with Photoprism Full (should it be almost empty regularly?)

[B Train]

Greetings unRaid Community,

 

I have one big question regarding my SSD cache: for some reason, cache is full and does not get 'emptied'.

 

Setup and use:

I use unRaid to backup family photos.

I have two HDDs (2TB EA) on the Array, no parity (for now) and one SSD (120GB) for cache.

I access the folder structure on the array via my windows file explorer and past my photos.

 

Question #1: Should the SSD cache become empty every time 'the mover' is invoked?

Based on what I have read and some YouTube tutorials, I suspect that the information is actually being rapidly saved on the 'SSD Cache' and then moved by 'the mover' to the actual Array composed of HDDs. Based on this information, the SSD should almost always be empty (please correct me if I am wrong). Also, how can I check information is being moved?

 

Question #2: Is Photoprism filling my SSD?

Now, I installed Photoprism, a docker program that allows me to index and display all of my photos on a gallery.

I know that dockers store their information on the SSD cache sometimes.

In the case of Photoprism, I know the program creates thumbnails and stores them in the SSD cache.

Does this mean that there can potentially a copy of each and everyone of my photos in the SSD cache and thus a bunch of information is occupying my SSD cache? I have 104GB out of 120GC of total storage.

 

Question #3: How can I check the information that does not move out of the cache is all related to Photoprism?

 

Thank you for your help, please let me know if I can provide any further information to clarify things.

[JorgeB]

10 hours ago, B Train said:

Question #1: Should the SSD cache become empty every time 'the mover' is invoked?

Depends how the share is configured.

 

 

[B Train]

On 11/19/2023 at 3:38 AM, JorgeB said:

Depends how the share is configured.

 

 

Is there a default?

Seems like the default would be for the cache drive to empty out as its purpose is to receive information quickly and to relay it to the slower HDDs?

I have looked through the documentation, I cannot find anything except for the following:

*App data contains "the data that the application itself uses to keep track of what it is doing. For example, plex keeps its library there, which is a database it uses to keep track of all your media."

https://docs.unraid.net/unraid-os/manual/docker-management/

 

I will continue working on this and report back.

Cheers

Edited November 25, 2023 by B Train

[ConnerVT]

Let's be sure we are all agreeing on our word definitions before getting too deep into this thread.

 

• Cache drive being the physical drive, which the Mover moves data (in this case, your photos) from the Cache to your data array.
• Appdata is the share where the docker containers keep their internal data (configurations, databases, cached information, etc).  It usually resides on the Cache drive for fast/improved docker performance.  Typically the Appdata share is configured as "cache only" and is never moved to the array.

I will assume that your photos are stored on your array.  My best guess what is happening is that the Photoprism appdata folder is just getting huge, which is one of the reasons I abandoned actively using it (Tried it - Didn't like it).  My appdata folder grew to be 31GB in size, nearly all of it being thumbnails.

 

 

 

Edited November 26, 2023 by ConnerVT

[dboonthego]

On 11/18/2023 at 4:45 PM, B Train said:

Does this mean that there can potentially a copy of each and everyone of my photos in the SSD cache and thus a bunch of information is occupying my SSD cache?

Yes, but it's not a 1:1 copy of your photos.  Originals are saved to the "Storage Path" which is typically an array share.  The thumbnails are stored inside the "Data Dir" path which is where the container lives.  Most likely /mnt/cache/appdata/photoprism/cache/thumbnails.

[B Train]

On 11/25/2023 at 6:07 PM, ConnerVT said:

Let's be sure we are all agreeing on our word definitions before getting too deep into this thread.

 

• Cache drive being the physical drive, which the Mover moves data (in this case, your photos) from the Cache to your data array.
• Appdata is the share where the docker containers keep their internal data (configurations, databases, cached information, etc).  It usually resides on the Cache drive for fast/improved docker performance.  Typically the Appdata share is configured as "cache only" and is never moved to the array.

I will assume that your photos are stored on your array.  My best guess what is happening is that the Photoprism appdata folder is just getting huge, which is one of the reasons I abandoned actively using it (Tried it - Didn't like it).  My appdata folder grew to be 31GB in size, nearly all of it being thumbnails.

 

 

 

Thank you for your insight it is greatly appreciated. You 'hit it on the nail' as some would say.

 

[B Train]

On 11/25/2023 at 7:46 PM, dboonthego said:

Yes, but it's not a 1:1 copy of your photos.  Originals are saved to the "Storage Path" which is typically an array share.  The thumbnails are stored inside the "Data Dir" path which is where the container lives.  Most likely /mnt/cache/appdata/photoprism/cache/thumbnails.

thank you dbonthego, this is super helpful.