It may be too much memory used by elasticsearch, I tested on a VM with 8GB RAM. You could try to limit the memory usage:
Don’t cross the 32 GB limit — if you have servers with a lot of memory, it is generally better to run more Elasticsearch nodes than going over the 32 GB limit for maximal heap size. In short, using
-Xmx32gor higher results in the JVM using larger, 64-bit pointers that need more memory. If you don’t go over-Xmx31g, the JVM will use smaller, 32-bit pointers by using compressed Ordinary Object Pointers (OOPs).
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