I've had the OOM killer happen with swapiness set to 0, 1, 10 and 30Hi,
how looks "cat /proc/sys/vm/swappiness" on the effected systems? Perhaps 0 instead of 1?
So far increasing the min_free_kbytes has prevented OOM events, also currently have swappiness set to 10.
The only thing using lots of RAM on my system is cache about 11GB when I experienced OOM events.
Only have 16GB RAM on these machines.