I was wondering if anyone knows a tool recreating a memory situation / memory load from an existing gc log to test different gc settings. With enough print parameters switched on it should be possible to create a similar load situation based on the collection times and the amount of surviving / collected data.
Does anyone know such a tool ?
You can not replay gc.log itself because it doesn't contain information about what kind of objects caused memory collection. If I were you, I'd have tried to recreate a realistic workload on your app and monitored how it worked. Then maybe 2x and 3x... loads to see how it scales. Which kind of app do you have? Is it a web server or a desktop application?
P.S. You could use VisualVM to see how GC works. There are also a couple of profiling tools there.