Question

I’m running a java web server as an internal component of another project, and unfortunately java insists on running in server mode (i.e. fast, and huge memory footprint), even when I pass the -client switch.

This is a problem because java takes up so much memory that my whole project is killed by the server.

I’m running java with the command:

java -client -classpath /home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/commons-fileupload-1.2.2.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/fop-20120125.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/xmlgraphics-commons-1.5svn.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/batik-all.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/docx4j-nightly-20120105.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/spark-0.9.9.3-SNAPSHOT.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/slf4j-log4j12-1.6.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/slf4j-api-1.6.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/jetty-webapp-7.3.0.v20110203.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/servlet-api-3.0.pre4.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/antlr-2.7.7.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/commons-codec-1.6.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/docx4j-2.7.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/poi-scratchpad-3.8-beta4.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/xalan-2.7.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/antlr-runtime-3.3.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/commons-io-2.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/serializer-2.7.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/xml-apis-1.3.04.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/avalon-framework-api-4.3.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/commons-lang-2.4.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/log4j-1.2.15.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/stringtemplate-3.2.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/avalon-framework-impl-4.3.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/commons-logging-1.1.1.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/poi-3.8-beta4.jar:/home/marcintustin/webapps/django/oneclickcosvirt/oneclickcos/java/wmf2svg-0.9.0.jar: Transcoder

java -version reports:

java version "1.7.0"
Java(TM) SE Runtime Environment (build 1.7.0-b147)
Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode)

As I’m on a shared host, I can’t install 32-bit compatibility libraries, so I can’t use the 32-bit JRE. This turns out to be a problem because as confirmed by @birryree in the comments (thanks!), 64-bit JRE always runs in server mode.

Is there a way to force java to run in normal client mode?

Answer 1

Based on comments received (and testing), it seems that the 64bit JVM ALWAYS runs in server mode, which means that it is VERY profligate with memory.

The work-arounds are:

1. Get the 32bit JVM (and appropriate compatibility libraries if on Linux); or
2. Use the -X options to limit memory to a certain maximum.