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Extremely slow performance and freezing



  • Daniel Johnson

    Just an update, I have uninstalled and reinstalled program.

    I had previously made a copy of all my photos from lightroom folder and made it a cataloged folder.

    This time I made the same folder again but imported the pictures and set to import into a new folder and catalogue. Seems to be behaving now.

    Even switching from thumbnail view to edit is alot faster.

    Export to jpg is still slow.

    What I did also notice is that the cache is set for 5000mb and when i deleted it windows was showing it at 14gb.


  • Brian Lawson Community moderator

    The cache size setting in Preferences does not control the on disk cache. It is for RAM cache and the disk usage will be whatever is needed to store the previews for all your images. This info came in response to a query sent to support.

    Also, be sure to configure your video card drivers per 

  • David Kick

    Brian, Just curious, why would you say the Cache setting in Preferences "does not control the on disk cache"? The slider for the Cache size clearly has a disk location that can be specified and seems to control the size of the disk cache.

    From the user guide:

    When you go through a folder of photos, Browse caches thumbnails and preview images as well as extracted metadata. This will make it faster the second time a user browses a folder. It also stores user-added or adjusted metadata such as ratings, labels, keywords, captions, rotation and GPS data, among others. (You can adjust the size of the cache and change the storage location of the cache in the Performance tab in ON1 Photo RAW 2019‘s Preferences window.)


  • Brian Lawson Community moderator

    As I said above, that info about cache size came from ON1 tech support. Both controls affect the cache, one its location on disk and the other its RAM footprint. I was confused too until I saw the support response. I don't question things like that, why bother. I just accept that I'm being told the truth and move on. The User Guide could be more clear about this and avoid the confusion.

    Think about it for a minute and you'll see the logic. If the amount of disk space was limited to the amount set in the preferences the program could only hold a limited number of browser previews which would force the program to keep regenerating them as you moved through your photos. That slows down the display of the previews which can be slow enough as it is.

    On my system I added an SSD that is dedicated to just the browser preview cache and scratch space so I don't really care how much disk space it occupies. There isn't anything else on that drive and never will be. As long as it doesn't run out of space for the program's scratch needs it can take as much preview cache space as is required. If drive holding the cache is used for other things I can see where it could be a concern but the solution is a dedicated drive.

  • David Kick

    Brian, As you read below please understand I am not trying to be argumentative but am simply trying to get a better understanding of the software settings and operation.

    I also use a separate SSD dedicated to the browser preview cache and scratch space.

    Sorry I missed the comment about being info from support. I guess that makes the Preference Dialog AND User Guide more than a bit confusing since neither makes reference to RAM usage for Browse Cache size slider.  This would also imply that one should throw in as much Ram as one could afford/system supports and MAX out the Cache size. I see the max setting  is 10GB so this would be about 31.3% of my 32GB system RAM. Going to play with the setting a bit to see what happens. 

    I hate to go here but sometimes Support people give wrong info or misinterpret a question. The reason I say this is the user guide suggests the Scratch Folder is the cache that uses memory and hard drive. Note you cannot control the Scratch folder size.

    From the user guide

    Scratch Folder Location
    This setting lets you move or reset your memory cache, which helps speed editing operations while you’re running Photo RAW. This is helpful if your system drive has limited space and wish to use a faster external drive as a cache. This cache information is purged each time you quit the application.

    There is also a Memory usage setting in preferences which defaults to 80%. Why would there be two settings? Does this mean that  the program can use up to 80% of my system RAM or 25.6GB and then the browse cache setting controls how much of that 25.6GB system RAM gets used for the browse cache? A max setting of 10GB would be about 39% of the 25.6GB. Seems to me if that was the case if a person only had 8 GB system RAM that would have to run a very small Browse Cache size to have enough system RAM for other operations.

    Memory Usage
    • System Usage: Specifies the amount of RAM that is used by the application. The maximum (default value) is 80%.

    • VRAM Usage: Specifies the amount of video memory (VRAM) that is used by the application. The maximum (default) is 80%.

     Sorry I rambled a bit but my train of thought went back and forth as I looked at the User Guide. 


  • Brian Lawson Community moderator

    No problem David, I understand completely the desire to want to know how the software operates so we can get the best performance from our systems.

    I agree that the manual is confusing in light of what we see on our drives and the response from support. I also agree that support can get it wrong some of the time. I'm still fighting with them about folder names sorting order where the names 1a, 1e, 1z consistently sort to 1a, 1z, 1e. They've made a few claims about how that isn't a bug and is to be expected for various reasons. Eventually I'm able to argue my point and get them to agree it is a bug in need of fixing.

    I cannot speak authoritatively about the memory settings but I agree with your assessment. The memory usage controls how much system RAM the program can utilize. Whether the browse cache setting comes strictly from the program's allotted memory or it is independent I do not know. What I do know is that I've seen my system's memory get filled to the point I have only 15MB (yes, MB!) left available for the system (on a 16GB laptop). This usually comes after extensive use of the Perfect Brush and/or AI masking. When it does happen it's time to quit the program to save my edits before it crashes and to release all ON1's memory back to the system. I will also quit all other programs I may have running while I continue to edit that particular image.

  • David Kick


    Thanks, like you and as I mentioned I have a small (240 GB) SSD dedicated to the Scratch and Browse folders so the discussion is not so much about drive space but about effective use of system memory.


    Would be nice if the On1 team clearly outlined how all these settings interact with each other and how best to optimize based on available system resources.


    I agree with closing down other programs. I use Chrome as my web browser but it is a major memory hog I always shut it down if I get into heavy editing. On my Windows machine I even have to go into Task Manager and shutdown running Chrome processes after closing Chrome.

  • Daniel Johnson

    Some great info here thanks.
    Why would it be a necessity to install a 2nd hdd just for the scratch ? I'm familiar with Lightroom and Acdsee and only time another hdd is installed is for photo storage.
    Good news is it's working perfectly now.

  • Brian Lawson Community moderator

    There is a whole lot of disk I/O going on while editing an image. When everything is sharing the same drive, the OS, the program, the photos, the programs temporary (work) space, and they are all trying to swap pieces in and out of memory there is a lot of disk contention taking place. It's like 4 lanes of traffic in 2 directions all funneling down to a one lane one way bridge, traffic gets backed up. Having a dedicated scratch drive adds a 2nd bridge to handle just that traffic. This was something I started doing years ago to improve Photoshop's performance.

    I also put the program's browse preview cache on it to remove that space requirement from my boot drive which is only 250GB. 10GB or more for image cache is significant and again there is less I/O contention and improved performance.


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