I would think that 28 instead of 30 for swapiness would not make much difference. However, it did make a difference. I started with the default values and I would try higher and lower. I started with 30, then 40. 40 was worse so I tried 35. It was better than 40 but worse than 30. So I went lower and tried 28. It was slightly better so I tried 26. It started getting worse again. I tried 24 and it was even worse. It was a very tedious process but that is what I did with every setting except the VM settings.