Forking benchmarks with long classpath on Windows (7)

[Dávid Karnok]

Hi,

I've been running JMH via Gradle from some time now on Windows (and Java
8u144), but my recent upgrade to Gradle 4+ lead to some problems. Gradle 4+
seems to add so many of its own jar files (irrelevant from the target
benchmark's perspective) to the classpath that when JMH tries to fork an
instance, the generated command line (in Runner::getForkedMainCommand,
System.getProperty("java.class.path")) creates a long String that, along
with the other short parameters of JMH, now exceed Windows' 32kb limit on
command lines, resulting in an IOException pointing to  CreateProcess.
Linux doesn't have this problem, however, the project needs at least
someone who tests and benchmarks on Windows.

Would it be possible that the Runner passed this long classpath string to
the to-be-forked java.exe in some other way (a temporary pathing jar)?
Alternatively, how feasible would be to support some kind of exclude filter
at this point in the Runner?

Unfortunately, I couldn't find a way to prevent Gradle (or the JMH plugin)
itself from passing that many classpath entries when it runs JMH.

-- 
Best regards,
David Karnok