Why the heap gets filled so fast?

Summary

I am very happy you are providing a port for Scala! It seems there is a memory leak, and I could not see a discussion about it: so I thought to start one.

I have just run this on an medium sized project with JAVA_OPTS="-Xms512m -Xmx12g " sbt stryker, and this is the state of the heap when it got to 40% of the test execution:

Now I guess you are running the test executions in parallel, but why they are not releasing resources? Any chance you could give a high level design of the test execution, so I could give a look into diagnose which bit of the codebase most likely is stealing resources? I would be happy to make this more usable for big projects.

Stryker4s config

stryker4s {
  mutate: [ "domain/src/main/scala/**/*.scala" ]
  test-filter: [ "xxx.yyyy.*" ]
  excluded-mutations: [
    "EqualityOperator",
    # "BooleanLiteral",
    # "ConditionalExpression",
    # "LogicalOperator",
    # "StringLiteral",
    # "MethodExpression"
  ]
}

Stryker4s environment

stryker4s 0.8.1

Your Environment

software	version(s)
Scala version	2.12.10
Build tool & version	sbt
Operating System	Ubuntu 20.04

[hugo-vrijswijk]

That is awesome to hear and certainly a good way to fix leaks 😁

[ag91]

Well it ran too fast for any metrics! Well done @hugo-vrijswijk ! I think we can close this 👍