Some applications with lots of code can produce an enormous number of ModuleExport events and associated constant pool data. After scrubbing an 85 MB recording from everything but ModuleExport events (and related constant pools) the size was reduce to 73 MB, a reduction of 15%.

jdk.ModuleExport 232 890 events

    Constant Pool Name Total Count Size Total Size (%)
    jdk.types.Package 232182 2.32 MiB 26.7 %
    jdk.types.Symbol 103377 6.15 MiB 70.6 %
    jdk.types.Module 20218 144 KiB 1.61 %
    jdk.types.ClassLoader 19755 97.7 KiB 1.1 %
    java.lang.Class 102 1.29 KiB 0.0145 %

These events provide practically no value, and users who want to diagnose module exports can easily run a small recording using the profile setting, or opt-in for the event:

    $ java -XX:StartFlightRecording:settings=profile ...
    $ java -XX:StartFlightRecording:jdk.ModuleExport#enabled=true ..