External SSD disk purgeable data

[Lise34734661z2ty]

Hello, I currently have my Lightroom Classic library on a OWC Envoy Pro FX 4 tb SSD external disk. I am getting close to it being full but I'm just back from a trip and need to clean up pics. I noticed that even though I deleted close o 2,500 RAW pics at 61 mpxl each I have not seen any reduction in space usage. Moreover the 'purgeable' GO keep increasing. I do not know whether I should delete the purgeable space or even how to. My LrC is in French but here is the data below on the disk space:

3,84 To - usable on 4 Tb

844,94 Go (87,77 Go purgeable) (left to use 844,04 but 87,77 Go purgeable that just increases as I delete pics)

3 082 903 920 640 octets (3,08 To sur disque) (Using 3,082 on the 3,84) 

I do have 'CleanMyMac' and I use it weekly on my Mac but I have never used it to clean the OWC disk as it only contained my Lightroom library. 

Thoughts, suggestions are welcomed. Thank you. 

[Conrad_C]

If the catalog folder is on that external volume, the most important file to look at for space saving is the one in the catalog folder with a filename that ends in: 

…Previews.lrdata

That is the Lightroom Classic previews cache, and it’s completely purgeable and expendable. If it is now much larger than any other file in the catalog folder, you can delete it to free up lots of space. Because it’s a cache, deleting it does not delete any critical data, and Lightroom Classic will start rebuilding it the next time you browse images.

I noticed that even though I deleted close o 2,500 RAW pics at 61 mpxl each I have not seen any reduction in space usage. Moreover the 'purgeable' GO keep increasing. I do not know whether I should delete the purgeable space or even how to.

By @Lise34734661z2ty

(You may know some of this already)

A file can be deleted from a Lightroom Classic catalog at two levels: 

It can be deleted from the catalog. 

It can be deleted from the catalog and the file system. 

If a file is only deleted from a catalog, the file may still exist in its folder in the file system so it still takes up space.

If a file is deleted from a catalog and the file system, then the file is moved to the macOS Trash, but it still takes up space until the Trash is emptied. 

On macOS, emptying the Trash may not free up as much space as expected if the volume is backed up using software that maintains local backup snapshot files (such as but not limited to Apple Time Machine). These are automatically created and purged by the backup software as needed. They are invisible in the Finder because (like most files called “purgeable”) we are not expected to manage them manually, they’re automatically purged periodically. However, it’s possible to delete local snapshots manually using Apple Disk Utility or the backup software. Similar to the Lightroom Classic previews file, after being deleted they will re-appear normally.

[Lise34734661z2ty]

Good morning, thank you for your answer. dI'm familiar with the previews.lrdata file but that one resides on my Mac. I did go and delete it just the same to see if it would have an impact on the external disk, which really contains only my pictures, but it did not. 

As for deleting pictures I always delete them at the 'disk' level In French it asks whether you wish to delete it from the catalog or the disk. But that is what seems weird. It doesn't seem to delete it from the disk. I also empty the trash at least twice daily. I do use Time Machine to do back-ups on an external back-up disk. I did a back-up last night and I still have this 87,77 G purgeable. It just keeps increasing as I delete more pictures. Here is a picture of the disk information: