Updated init, systemd, jvm.options and tests

templates/jvm.options.j2

@@ -20,13 +20,9 @@
 # Xmx represents the maximum size of total heap space
 {% if es_heap_size is defined %}
 -Xms{{ es_heap_size }}
-{% else %}
--Xms2g
-{% endif %}
-
-{% if es_heap_size is defined %}
 -Xmx{{ es_heap_size }}
 {% else %}
+-Xms2g
 -Xmx2g
 {% endif %}
 
@@ -47,9 +43,6 @@
 
 ## optimizations
 
-# disable calls to System#gc
--XX:+DisableExplicitGC
-
 # pre-touch memory pages used by the JVM during initialization
 -XX:+AlwaysPreTouch
 
@@ -67,7 +60,10 @@
 # use our provided JNA always versus the system one
 -Djna.nosys=true
 
-# flags to keep Netty from being unsafe
+# use old-style file permissions on JDK9
+-Djdk.io.permissionsUseCanonicalPath=true
+
+# flags to configure Netty
 -Dio.netty.noUnsafe=true
 -Dio.netty.noKeySetOptimization=true
 -Dio.netty.recycler.maxCapacityPerThread=0
@@ -100,6 +96,14 @@
 # ensure the directory exists
 #-Xloggc:${loggc}
 
+
+# By default, the GC log file will not rotate.
+# By uncommenting the lines below, the GC log file
+# will be rotated every 128MB at most 32 times.
+#-XX:+UseGCLogFileRotation
+#-XX:NumberOfGCLogFiles=32
+#-XX:GCLogFileSize=128M
+
 # Elasticsearch 5.0.0 will throw an exception on unquoted field names in JSON.
 # If documents were already indexed with unquoted fields in a previous version
 # of Elasticsearch, some operations may throw errors.