There should be a way to run the 20 instances of your Java program as different threads inside just one Java Virtual Machine (JVM) process.

It may be more effective than 20 parallel JVM processes fighting for the same system resources (RAM+CPU) as Java is not very friendly in that regard.

Update: There is Nailgun!

In reply to Re: Run a script in parallel mode by salva
in thread Run a script in parallel mode by Anonymous Monk

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