roles/elastic-stack: update jvm.options template per upstream elasticsearch updates

roles/elastic-stack/ansible-elasticsearch/templates/jvm.options.j2

@@ -47,9 +47,22 @@
 ################################################################
 
 ## GC configuration
--XX:+UseConcMarkSweepGC
+8-13:-XX:+UseConcMarkSweepGC
--XX:CMSInitiatingOccupancyFraction=75
+8-13:-XX:CMSInitiatingOccupancyFraction=75
--XX:+UseCMSInitiatingOccupancyOnly
+8-13:-XX:+UseCMSInitiatingOccupancyOnly
+
+## G1GC Configuration
+# NOTE: G1 GC is only supported on JDK version 10 or later
+# to use G1GC, uncomment the next two lines and update the version on the
+# following three lines to your version of the JDK
+# 10-13:-XX:-UseConcMarkSweepGC
+# 10-13:-XX:-UseCMSInitiatingOccupancyOnly
+14-:-XX:+UseG1GC
+14-:-XX:G1ReservePercent=25
+14-:-XX:InitiatingHeapOccupancyPercent=30
+
+## JVM temporary directory
+-Djava.io.tmpdir=${ES_TMPDIR}
 
 ## optimizations
 
@@ -96,14 +109,24 @@
 # ensure the directory exists and has sufficient space
 -XX:HeapDumpPath=/var/lib/elasticsearch
 
+# specify an alternative path for JVM fatal error logs
+-XX:ErrorFile=/var/log/elasticsearch/hs_err_pid%p.log
+
 ## GC logging
 
-#-XX:+PrintGCDetails
+## JDK 8 GC logging
-#-XX:+PrintGCTimeStamps
+
-#-XX:+PrintGCDateStamps
+# 8:-XX:+PrintGCDetails
-#-XX:+PrintClassHistogram
+# 8:-XX:+PrintGCDateStamps
-#-XX:+PrintTenuringDistribution
+# 8:-XX:+PrintTenuringDistribution
-#-XX:+PrintGCApplicationStoppedTime
+# 8:-XX:+PrintGCApplicationStoppedTime
+# 8:-Xloggc:/var/log/elasticsearch/gc.log
+# 8:-XX:+UseGCLogFileRotation
+# 8:-XX:NumberOfGCLogFiles=32
+# 8:-XX:GCLogFileSize=64m
+
+# JDK 9+ GC logging
+# 9-:-Xlog:gc*,gc+age=trace,safepoint:file=/var/log/elasticsearch/gc.log:utctime,pid,tags:filecount=32,filesize=64m
 
 # log GC status to a file with time stamps
 # ensure the directory exists