isomarcte / http4s-jdk-client-body-resource-leak

Repo to demonstrate a resource leak in certain versions of the http4s-jdk-client

Demonstrates a resource leak in the response body handling of the http4s-jdk-client present in version <= 0.3.3. This issue is particularly difficult to demonstrate in a unit test, which is why I wrote this toy project.

It stands up a http4s ember server and then using the JDK client to repeated run client.status against it. It prints out the number of requests sent every 1000 requests.

When I give the JVM ~200MiB of heap space it starts failing due to out of memory errors between 6000 and 7000 requests, which takes about 15 seconds on my computer.

To run,

sbt clean compile
sbt -J-Xmx200M run

Or just run ./run-leak-test.sh which does the exact same thing.

A fix for this is here, http4s/http4s-jdk-http-client#335. You can locally publish that commit and then change the version in the build.sbt of this project. Running on that version will run forever, using constant memory, as expected.