Fix Heroku deploy

Author: commjoen

Dockerfile.web

@@ -39,8 +39,9 @@ ENV default_aws_value_challenge_11=$CHALLENGE_11_VALUE
 ENV BASTIONHOSTPATH="/home/wrongsecrets/.ssh"
 ENV PROJECTSPECPATH="/var/helpers/project-specification.mdc"
 ENV funnybunny="This is a funny bunny"
-# Keep memory usage within Heroku dyno limits.
-ENV JAVA_TOOL_OPTIONS="-XX:MaxRAMPercentage=60 -XX:InitialRAMPercentage=25 -XX:MaxMetaspaceSize=128m -XX:+UseSerialGC -XX:+ExitOnOutOfMemoryError"
+# Keep memory usage within Heroku dyno limits (512MB dyno).
+# Hard cap heap to 250M, metaspace to 60M, disable expensive GC, exit on OOM immediately.
+ENV JAVA_TOOL_OPTIONS="-Xmx250M -Xms128M -XX:MetaspaceSize=40M -XX:MaxMetaspaceSize=60M -XX:CompressedClassSpaceSize=32M -XX:+UseG1GC -XX:MaxGCPauseMillis=50 -XX:+ExitOnOutOfMemoryError -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/tmp/heapdump.hprof"
 # Deploy WrongSecrets to Heroku
 COPY .github/scripts/ /var/helpers
 COPY src/test/resources/alibabacreds.kdbx /var/helpers