Photoshop does not empty cache files until program is cloesd

[milner-studios]

It appears that photoshop or camera raw are not deleting there caches as files are closed. They seem to remain persistent until the program is closed. This can be problematic when working with extremely large files. Is there something I am missing to solve this issue?

[Conrad_C]

I think they intend for caches to persist until quit because the point of a cache is to load recently used data faster than going back to the original document and recalculating recent actions, saving time. And part of the assumption is that you might re-open a document you recently closed, so don’t dump that cache just yet. But it’s been recognized that sometimes Photoshop paints itself into a corner, in terms of memory, so if that’s happening, you can try choosing the commands on the Edit > Purge submenu. Those commands do purge certain types of items that Photoshop might be holding in RAM, but I don’t think we can assume those commands are a complete purge of Photoshop RAM.

If this happens a lot, it’s a sign that the computer probably doesn’t have enough RAM for the sizes and types of Photoshop documents that are typically edited on that computer. If free space on the system volume also gets low during Photoshop edits, that’s a sign that a large scratch disk needs to be assigned to Photoshop, or the system drive needs to be larger.

[milner-studios]

Yes I think you may be right. It may be time to do some updates. The edit purge is my friend and can help out sometimes when I cannot save the file l’m working on as all ram and scratch disks are full and all other files have been closed. I wish there was an option that could adjust how photoshop behaves to maximise cache when working with extreme file sizes and could purge trapped ram/scratch space from non current file tasks in these extreme cases. Always trying to find the best methods/sequence to allow maximum work within an editing session. The problems of limited work funds. 

[D Fosse]

The camera raw cache is supposed to remain. That's the whole point, otherwise there wouldn't be any need for it.

As for Photoshop, it's important to realize that the scratch disk is always in use. RAM acts as a fast access cache to the scratch disk's main memory. This way, most current memory activity can be executed in RAM, while scratch disk activity can be run in the background. With a fast disk and enough space, the process is streamlined and seamless.

There is no such thing as enough RAM, and there is no point trying. A scratch file can easily be 100 GB or more.

Memory is by design not released until you exit the application. Reusing it is much faster than re-requesting it from the operating system. You set allocation in preferences to ensure there is always enough left for other applications and system processes. Note that ACR runs in its own address space, so it needs memory outside Photoshop.

[milner-studios]

Thanks for your help