See the attached jpg that shows the Resource Monitor. The longer LR is open the more RAM it consumes.
Can you help experiment a little bit more? What are you doing in Lightroom when this happens?
See https://helpx.adobe.com/lightroom/kb/lightroom-downloads.html on how to revert back to the specific version of Lr. Basically you uninstall your current version. Download and install the Lr 6.0, and then download and install the specific patch for the minor version.
Lightroom version: 6.5 [ 1067055 ]
LanguageVersion: 3.30 NVIDIA via Cg compilerRenderer: GeForce GT 640/PCIe/SSE2Version: 3.3.0 NVIDIA 353.82Vendor: NVIDIA CorporationCheck OpenGL support: PassedGeForce GT 640/PCIe/SSE2Graphics Processor Info: Input types: Multitouch: No, Integrated touch: No, Integrated pen: No, External touch: No, External pen: No, Keyboard: NoDisplays: 1) 2560x1440, 2) 2560x1440Desktop composition enabled: YesSystem DPI setting: 96 DPICamera Raw SIMD optimization: SSE2,AVX,AVX2Maximum thread count used by Camera Raw: 8Memory cache size: 0.0 MBVirtual memory used by Lightroom: 7885.9 MBReal memory used by Lightroom: 2574.6 MB (7.8%)Real memory available to Lightroom: 32706.7 MBBuilt-in memory: 32706.7 MBProcessor speed: 3.4 GHzLogical processor count: 8System architecture: x64Application architecture: x64Version: 10.0Operating system: Windows 10License: Perpetual
Make sure Face Detection is paused, Address Lookup is paused, and LR Mobile Sync is paused if applicable. Just to make sure these aren't affecting the memory usage.
Face Detection uses 10s of MBs per image with my mostly non-people images so maybe if there are people it's finding those could pile up in memory, not sure. In any case, allocating and freeing the memory per picture may fragment memory.
I have 80,000 images in my catalog, opened it 10 minutes ago and it's risen from 700MB to 750MB but seems to have settled down, both the handles and the memory, so I don't know as it's going to use up everything if it sits overnight. I have all the above background processes paused.
I can imagine a scenario where something in the preview cache is corrupted and LR is seeing an error while trying to compute a preview and tries to regenerate the same preview over and over and not cleaning up since the process is aborting prematurely. A way to test for this would be to create an entirely new catalog and just let that sit, then import a few photos, and let it sit some more and see if the behavior changes.
I can also imagine some problem if there is a video in one of the folders that is causing an error somehow and LR retrying to scan it or do whatever it does with videos over and over and losing memory each time due to aborting the process due to an error.
One more thing to check, disable any Auto Import that is configured, in case LR is actually checking for imports every few seconds and that process is eating memory.
It would be interesting to hear from Simon on what happened with the original poster's situation when instrumentation was attached to the LR process and things debugged.
I am presuming that you have a custom build PC, not an OEM in my next points. I have a similar system in spec, just a different gfx card &.it used to struggle at LR4, that machine sits in the corner not used these days.
FYI LR catalog uses RAM, as you have loads, I can presume everything else uses either CPU or GPU Horsepower, as we are talking massive numbers of computations just for one image. A memory leakage would effect more than a program, as you are referring to a coding term, I feel that windows security centre or system log would throw something up & Also it would crash.
I would check your bios & drivers, then windows updates, then presuming you are HDD not SSD, perform a hard drive check, read & write speeds, if you are having large data stuck in RAM, this is hardware & driver related, especially if you move large of files round, also switch off any windows related search functions. Also do not use windows tools for hardware, they lie, have done since windows 95.
Please post the size of LR Catalog and other associated folders in thread & also number of images currently in LR Catalog and I will confirm if Catalog is corrupt.