I don't know why you are seeing slower performance when the photos are on the SSD (not SDD), but there's no reason to put the photos on the SSD in the first place, you would not see a noticeable increase in speed by putting photos on a SSD (see this study: Will an SSD Improve Adobe Lightroom Performance? | Computer Darkroom)
Thanks for your help DJ.
The reason I need to have photos on my laptop's SSD is to work on them when I'm away from home. I travel quite often and sometimes for extended periods of time. My external HDD is in a rather heavy four-drive enclosure; it's not very portable.
What's baffled me is: LR performance was stellar when accessing photos on both external HDD and internal SSD until recently. I was happy with the set-up, and, whether or not one drive was faster than the other didn't matter to me, they both were FAST. When performance slowed on the SDD I tried optimizing LR and making more space on the SDD......that didn't help at all; it's still crawling.
Today it takes 7 seconds just to load a 1:1 view of a photo on SDD, less than 2 seconds on HDD. I always have 1:1 previews rendered on import and never deleted (this is why I have > 50GB of previews).
WHY the SDD slowdown with over 300GB free space?
If my preview cache is too big, then why are operations not slower on the HDD as well?
Should I uninstall LR5 and reinstall it? It's working just fine with photos on the HDD.
I am subscribed to the Creative Cloud with LR and PS. I have "Adobe Photoshop Lightroom" (version 5.6) and (from a recent update) "Adobe Photoshop CC 2014" so I deleted "Adobe Photoshop CC". I subsequently read somewhere that I should have kept both "Photoshop CC" and "Photoshop CC 2014"...not sure if that would be causing the slowdown, but, again....why only on the SDD?
I'll have a guess at this. If you only have one ssd in your laptop, the cpu has to access the LR program files, the ACR cache files, the LR preview files, the LR catalog, the LR previews.db, the LR rootpixels.db, some temporary files that it creates during processing, as well as your image file - all on the one ssd. I may have missed something, but that is at least 8 files (and probably many more) that have to be accessed all at once to process your image. And that is without all the Windows files, pagefile, etc that will be in use from the same ssd.
Although SSDs are fast, they can only do one thing at a time. But the cpu can access your images on your usb drive independently of the 'fight' for access to the ssd files. So getting the image from the usb drive is quicker than waiting for it in the queue to and from your ssd. This is just a guess, but I suspect your I/O system is just overloaded with getting all the requisite files to the cpu so it takes longer.
I only use a desktop, and as I'm a bit of a 'perfectionist' or 'nutcase' (whichever you prefer!), I have one ssd for my system, where LR has all it program files and temporary files, one ssd for my LR catalog, previews & previews.db, and another ssd which has various stuff on it including the LR ACR cache files. My 90K images are on a big internal HDD. In my reckoning, this means that the cpu can be getting all the LR stuff from 4 different drives, all at more or less the same time.
I don't know how many images you have, but I use a small 2.5" WD Passport usb3 drive when travelling which is 2TB. It holds all my 90K images. 1TB versions are also available and cheaper, and they don't need a separate power supply.
Bob...thank you for your very educated "guess"! There are a LOT of files being bandied about, I had no idea my poor 1TB internal SSD was in such distress. Not sure about those Windows page files...I'm using a MacBook Pro, not a Windows machine.
But you may be right, perhaps my I/O system is simply overloaded.
It's just odd that it was working plenty fast not long ago.
I have 80K images, about 7K are on my laptop, the rest are on the external HDD.
Not being very technical, I'm not sure if you supplied me with a solution to this fix I'm in.
Yes, I could buy a desktop machine with multiple SSDs; one for LR's program and temp files, another for the catalog, previews, previews db, and a third SSD for ACR cache files. But the bottom line is: I simply can't do that.
1) Do some kind of check on my internal SDD to make sure it's OK? Any suggestions on how to do that?
2) Move ALL my photos to my external HDD? This becomes a pain when I have to move some of them back to go mobile. BTW, thanks for the info on the passport drives...how fast are they compared to the speed of your big internal HDD?
3) Un-install and re-install Adobe Photoshop Lightroom and/or Adobe Photoshop CC 2014? Not sure if that would make a difference.
Bob, thanks again for your help, any further advice is greatly welcomed.