Problem summary
Nuke Cache Directories can exceed 100% of use causing extreme slowdowns in Linux
Customer reported version
nuke.10.5v5
Customer reported platform
centos6
Steps to reproduce
1) Open the attached Nuke script
2) Navigate to the preferences (Shift + s in the viewport), and adjust your cache settings similar to the screenshot below.
3) These values will add up to 100%, and will cause significant slowdowns as Nuke will then attempt to utilize all of the available memory for it's cache.
4) This issue can also spread to other aspects of the Cache settings, such as the "comp disk cache size" and "rotopaint cache size" where you can adjust these values to exceed the amount of available memory on your machine.
5) WARNING: THIS ADDITIONAL STEP CAN CAUSE HARM TO YOUR MACHINE, PLEASE BE CAUTIOUS.
- To further exacerbate the issue, you can adjust these cache settings to values that exceed their limits which can cause nuke to utilize space on the users machine that does not exist.
1) Set the Comp disk cache size and rotopaint cache size to values that exceed 100GB
2) Set the playback cache size to values that exceed 100
3) Set the comp playback cache size, (% of comp cache) to values that exceed 50
4) Set the comp paint cache size (% of comp cache) to values that exceed 90
5)From here simply create a checkerboard and a rotopaint and create a series of paint strokes on every frame until nuke crashes.
At this point Nuke will begin to use resources on the computer which do not exist and in a linux environment can be extremely difficult to deal with, so once again please be extremely cautious when reproducing this issue.
Workaround
-Be aware of the memory limitations and space on your machine when setting these variables.
-Keep the comp disk cache size and rotopaint cache sizes relatively small (Somewhere between 10 and 20 GB, based on available memory on your disk)
- With regards to Memory Caching, On our testing machines I set the Playback Cache Size to 16GB, Comp Cache Size to 30, Comp Playback Cache Size to 30 and
comp paint cache size to 30
Reproduced by support
Reproduced by Support on Linux CentOS 7;
Does not occur in Windows 7/10 or MacOS 10.12.
Nuke 11.1v1 - Linux CentOS 7.4
Nuke10.5v5 - Linux CentOS 7.0
Unable to reproduce bug in:
Windows 7/10
MacOSX 10.12
Earliest version tested
Nuke10.5v5
Expected behaviour
Nuke would limit it's caching behavior disabling any values that exceed maximum usage
Actual behaviour
Nuke has no limit to how much memory it can use in the Cache, if these values are adjusted beyond the values of what the machine can handle nuke will continue to utilize all available resources including virtual memory and will either crash or cause Nuke to be extremely slow.
