Re: [jetty-users] Can the warning about system properties and JVM args b

[Shawn Heisey <eclipse@xxxxxxxxxxxx>]

On 3/22/2016 8:22 AM, Joakim Erdfelt wrote:
> What system properties are you using?
> And why not use --exec if you are using System properties?

On a machine running Solr that I started with our init script,
this is the whole commandline:

/usr/lib/jvm/java-8-oracle/bin/java -server -Xms18g -Xmx18g
-XX:NewRatio=3 -XX:SurvivorRatio=4 -XX:TargetSurvivorRatio=90
-XX:MaxTenuringThreshold=8 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC
-XX:+CMSScavengeBeforeRemark -XX:PretenureSizeThreshold=64m
-XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=70
-XX:CMSMaxAbortablePrecleanTime=2000 -XX:+CMSParallelRemarkEnabled
-XX:+ParallelRefProcEnabled -verbose:gc -XX:+PrintHeapAtGC
-XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps
-XX:+PrintTenuringDistribution -XX:+PrintGCApplicationStoppedTime
-Xloggc:/index/solr5/logs/solr_gc.log -Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.local.only=false
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.port=18982
-Dcom.sun.management.jmxremote.rmi.port=18982 -Djetty.port=8982
-DSTOP.PORT=7982 -DSTOP.KEY=solrrocks -Duser.timezone=UTC
-Djetty.home=/opt/solr5/server -Dsolr.solr.home=/index/solr5/data
-Dsolr.install.dir=/opt/solr5
-Dlog4j.configuration=file:/index/solr5/log4j.properties -jar start.jar
-XX:OnOutOfMemoryError=/opt/solr5/bin/oom_solr.sh 8982 /index/solr5/logs
--module=http

This is running Jetty 9.2.13.

We are aware that the placement of the OnOutOfMemoryError option is
incorrect, this will be fixed in our next version.

I finally did manage to locate a webpage that mentions the "--exec"
option.  It says "Starts a forked instance of Jetty."  I have some clue
what all the words mean, but not what the effective result of that
option is.  My best guess is that it starts Jetty in the background.
This is good for our normal start mode, but we also have a foreground
option.

I wasn't involved with writing the start script.  It looks like we are
starting Jetty in the background using the "nohup" command.  I don't
know if this is just because it's a convenient option, or because
immunity to HUP signals was actually desired.  In the Windows start
script, background operation is accomplished with "START /B".

Thanks,
Shawn