§Increase Memory for sbt and Maven
Lagom in dev mode starts all your services plus some internal Lagom services in a single JVM. This can cause
OutOfMemoryErrors depending on your JVM setup. It is possible to start Maven and sbt with increased memory.
We recommend you increase the Maximum Metaspace size and the Thread Stack size. These values can be set using
-Xss2M -XX:MaxMetaspaceSize=1024M. The exact values may depend on your hardware and your code base.
You can start Maven with extra memory using
MAVEN_OPTS environment variable.
$ MAVEN_OPTS="-Xms512M -Xmx1024M -Xss2M -XX:MaxMetaspaceSize=1024M" mvn lagom:runAll
In this example we’re setting an initial JVM Heap of 512Mb, a maximum Heap of 1024M, a thread stack of 2M and maximum Metaspace size of 1024M.
MAVEN_OPTS on every invocation is error prone and exporting it globally might not be possible if you need different settings for different projects. You may want to use direnv to setup the environment variables per project.
You can start sbt with extra memory using
SBT_OPTS environment variable.
$ SBT_OPTS="-Xms512M -Xmx1024M -Xss2M -XX:MaxMetaspaceSize=1024M" sbt
sbt lets you list the JVM options you need to run your project on a file named
.jvmopts in the root of your project.
$ cat .jvmopts -Xms512M -Xmx4096M -Xss2M -XX:MaxMetaspaceSize=1024M
sbt also supports other means to tune the underlying JVM. See
sbt -h for more details.