The Jetty documentation shows how the location of the temporary directories can be controlled
http://www.eclipse.org/jetty/documentation/current/ref-temporary-directories.html

I just did a quick experiment by adding a call to WebAppContext#setTempDirectory() in HostConfiguration#create()
https://github.com/jenkinsci/winstone/blob/master/src/java/winstone/HostConfiguration.java

i.e.

wac.setTempDirectory(new File("/var/cache/jenkins/temp"));

When jenkins.war was built with a version of winstone.jar containing that the Jetty temporary directory moved away from /tmp into /var/cache/jenkins/temp

That isn't a full solution to the problem because it needs hooking into the --webroot argument to jenkins.

There are other issues relating to how it works with multiple webapps (they should not share the same temp directory) and the usage of the temp folder is slightly different (it uses a /webapp subdirectory) to the old native winstone behaviour.

I don't know the internal plumbing of Winstone/Jenkins well enough to make a stab at a full fix for this.

I bumped into this issue trying to run jenkins in my NAS where the tmp is just 30MBs. Overriding the java system property (java.io.tmpdir) worked for me!

E.g.

nohup java -Djava.io.tmpdir=./webroot -jar jenkins.war --httpPort=9999 > ./jenkins.log 2>&1 &

The following worked better for me:

Set the jetty.home to Jenkins directory on the java opts when starting Jenkins

-Djetty.home=$JENKINS_HOME

Create a directory called "work" in Jenkins Home directory, or wherever you have set jetty.home

That will cause Jetty to use that work directory instead of whatever the java.io.tmpdir property is set to.

See JENKINS-22442
It should fix the issue reported here.

Duplicate of JENKINS-22442