Indicator would be if you’re seeing an unusually high amount of system swapping with a good amount of free memory available.
Realistically you should be able to ignore that VM warning if the majority of your memory is in use by ARC as it should resize itself as needed, though I’ve found it one of the best ways to reproduce the memory/swap issues mentioned above without a fix applied ;).
If you’re looking to test, try disabling swap as suggested by iX and seeing if that fixes the issue.