Does Neo4j calculate JVM heap on Ubuntu?

Question

In the neo4j-wrapper.conf file I see this:

# Java Heap Size: by default the Java heap size is dynamically
# calculated based on available system resources.
# Uncomment these lines to set specific initial and maximum
# heap size in MB.
#wrapper.java.initmemory=512
#wrapper.java.maxmemory=512

Does that mean that I should not worry about -Xms and -Xmx?

I've read elsewhere that -XX:ParallelGCThreads=4 -XX:+UseNUMA -XX:+UseConcMarkSweepGC would be good. Should I add that on my Intel® Core™ i7-4770 Quad-Core Haswell 32 GB DDR3 RAM 2 x 240 GB 6 Gb/s SSD (Software-RAID 1) machine?

Answer 1

I would still configure it manually. Set both to 12 GB and use the remaining 16GB for memory mapping in neo4j.properties. Try to match it to you store file sizes