1 ## JVM configuration

     2 

     3 ################################################################

     4 ## IMPORTANT: JVM heap size

     5 ################################################################

     6 ##

     7 ## You should always set the min and max JVM heap

     8 ## size to the same value. For example, to set

     9 ## the heap to 4 GB, set:

    10 ##

    11 ## -Xms4g

    12 ## -Xmx4g

    13 ##

    14 ## See https://www.elastic.co/guide/en/elasticsearch/reference/current/heap-size.html

    15 ## for more information

    16 ##

    17 ################################################################

    18 

    19 # Xms represents the initial size of total heap space

    20 # Xmx represents the maximum size of total heap space

    21 

    22 -Xms512m

    23 -Xmx512m

    24 

    25 ################################################################

    26 ## Expert settings

    27 ################################################################

    28 ##

    29 ## All settings below this section are considered

    30 ## expert settings. Don't tamper with them unless

    31 ## you understand what you are doing

    32 ##

    33 ################################################################

    34 

    35 ## GC configuration

    36 -XX:+UseConcMarkSweepGC

    37 -XX:CMSInitiatingOccupancyFraction=75

    38 -XX:+UseCMSInitiatingOccupancyOnly

    39 

    40 ## optimizations

    41 

    42 # disable calls to System#gc

    43 -XX:+DisableExplicitGC

    44 

    45 # pre-touch memory pages used by the JVM during initialization

    46 -XX:+AlwaysPreTouch

    47 

    48 ## basic

    49 

    50 # force the server VM

    51 -server

    52 

    53 # set to headless, just in case

    54 -Djava.awt.headless=true

    55 

    56 # ensure UTF-8 encoding by default (e.g. filenames)

    57 -Dfile.encoding=UTF-8

    58 

    59 # use our provided JNA always versus the system one

    60 -Djna.nosys=true

    61 

    62 # flags to keep Netty from being unsafe

    63 -Dio.netty.noUnsafe=true

    64 -Dio.netty.noKeySetOptimization=true

    65 

    66 # log4j 2

    67 -Dlog4j.shutdownHookEnabled=false

    68 -Dlog4j2.disable.jmx=true

    69 -Dlog4j.skipJansi=true

    70 

    71 ## heap dumps

    72 

    73 # generate a heap dump when an allocation from the Java heap fails

    74 # heap dumps are created in the working directory of the JVM

    75 -XX:+HeapDumpOnOutOfMemoryError

    76 

    77 # specify an alternative path for heap dumps

    78 # ensure the directory exists and has sufficient space

    79 #-XX:HeapDumpPath=${heap.dump.path}

    80 

    81 ## GC logging

    82 

    83 #-XX:+PrintGCDetails

    84 #-XX:+PrintGCTimeStamps

    85 #-XX:+PrintGCDateStamps

    86 #-XX:+PrintClassHistogram

    87 #-XX:+PrintTenuringDistribution

    88 #-XX:+PrintGCApplicationStoppedTime

    89 

    90 # log GC status to a file with time stamps

    91 # ensure the directory exists

    92 #-Xloggc:${loggc}

    93 

    94 # Elasticsearch 5.0.0 will throw an exception on unquoted field names in JSON.

    95 # If documents were already indexed with unquoted fields in a previous version

    96 # of Elasticsearch, some operations may throw errors.

    97 #

    98 # WARNING: This option will be removed in Elasticsearch 6.0.0 and is provided

    99 # only for migration purposes.

   100 #-Delasticsearch.json.allow_unquoted_field_names=true