OOMKilled/137 definitely means that your pod asked an Openshift for more memory and this level exceeded the configured memory limit.

We had similar situation in java app and the solution in our case was to change GC type to G1 and to reduce -Xmx limit for heap. Remember that pod memory limit has to be greater than -Xmx + metaspace limit + other memory, e.g. finally we had: -Xmx=500 MB plus 400 MB for non-heap other memory segments, so pod memory limit was 900 MB.