start.sh

    java_opts="$java_opts -XX:MaxGCPauseMillis=50"

    # Disable explicit GC. Some plugins may think it's a good idea to manually run the garbage collector.
    # This is never a good idea with our setup, as it introduces a pause that is usually completely avoidable.
    java_opts="$java_opts -XX:+DisableExplicitGC"


    ### OPTIMIZATION SETTINGS ###

    # Bukkit and Spigot synchronize things for thread safety. Some of these synchronizations are never contested under ideal conditions.
    # This option optimises those cases so that uncontested syncs become much cheaper.
    java_opts="$java_opts -XX:+UseBiasedLocking"

    # Turn on performance optimizations that are expected to be turned on by default in future versions of Java.
    # This generally can't hurt, but comment it out if java.lang.UnsupportedOperationExceptions appear at startup.
    java_opts="$java_opts -XX:+AggressiveOpts"

    # Enable optimization of getter functions, an easy way to reduce some function overhead.
    java_opts="$java_opts -XX:+UseFastAccessorMethods"


    ### MEMORY MANAGEMENT ###

    # Enable HugePages support to improve memory access performance in the OS. We have 8GB of RAM dedicated to HugePages.
    #java_opts="$java_opts -XX:+UseLargePages"

    # Raise the maximum size of the Permanent Generation area (which stores class data, and static data like string literals)
    # to 128MB (default is 64MB) so we don't run out of PermGen space. The CMSClassUnloading should help with this though.
    # The PermGen space is GOING AWAY in Java 8, since this data will be stored in native memory instead ("Metaspace").
    # The replacement option will be: -XX:MaxMetaspaceSize
    #java_opts="$java_opts -XX:MaxPermSize=128m"
    java_opts="$java_opts -XX:MaxMetaspaceSize=256m"

    # Adjust the Target Survivor Ratio: This basically determines how full the GC is letting the Survivor generations get before
    # moving things into the Old generation. By using a higher value we improve efficiency of memory use, but lose some "overhead"
    # that would absorb allocation spikes. Default is 50%, our setting is 80%, some servers go as high as 90%.
    java_opts="$java_opts -XX:TargetSurvivorRatio=80"

    # I would love to adjust XX:SurvivorRatio, XX:MaxTenuringThreshold etc to suitable values, but http://i.imgur.com/ntELi.jpg
    # I don't know what a Minecraft server's requirements are, though inspection through a profiler may reveal the details.

    # Big eden, smaller survivor area. Minecraft tends to create large quantities of short-lived objects as part of its processing
    # of game data, compared to a smaller amount of long-lived objects, so we want to prioritize the eden area of memory.
    # NOTE: This is probably ignored because we didn't specify -XX:-UseAdaptiveSizePolicy
    java_opts="$java_opts -XX:SurvivorRatio=10"


    java_opts="$java_opts -classpath apache-log4j-2.8-bin"
    ### END OF JAVA OPTIONS ###