Error occurred during initialization of VM Could not reserve enough space for object heap?

I have a little problem with my network.

As soon as I started 5 Minecraft servers with the proxy, but the 6.7.8 comes…

this mistake:

Error occurred during initialization of VM

Could not reserve enough space for object heap

I suspect it's because too many cmd windows are open, but well, please help.

The memory of your PC is limited, you know?

Well the error message says clearly that you have no RAM left for more servers.

Thank you. Google Translate best xD

The VM clearly says that it can't allocate enough memory. So you do not have enough memory. (have already mentioned in a post below yes that you have "only" 8gb available.