this is RT version of PERF-121.
The problem is that memory usage increases every iteration for about 2Mb (it looks like the amount depends on number of players).
This is looks like some native leak. At least (Eclipse) MemoryAnalyzer shows that heap is very small (just couple Mb).
The only suspicious leak in java is com.sun.media.jfxmediaimpl.NativeMediaPlayer.

To run the benchmark you can use ant target run-mediasystem-180_24p_36players-bm in tests/performance/MediaSystemTest directory.