Problem Java out of memory error: unable to create new native thread

[brainbaobao]

I am running an FTB Unleashed 1.1.7 server with all mods enabled on 5G of RAM, hosted by prominecrafthost.
Recently(a few hours ago) the server started crashing and popping out the error http://pastebin.com/BxA
This is the crash report:
http://pastebin.com/BxAc5N2p

As said above, the server has 5G of RAM, 20 plugins(all correct versions of MC), and usually has 5-7 players on it.
What could I do to fix this?

 

[nallar]

Why do you have "-Xss2M" as a JVM argument? Increasing stack size shouldn't be necessary and will reduce the maximum number of threads you can have. This crash is happening because you're running out of memory for threads.

 

[brainbaobao]

Why do you have "-Xss2M" as a JVM argument? Increasing stack size shouldn't be necessary and will reduce the maximum number of threads you can have. This crash is happening because you're running out of memory for threads.

The host configured it as is. I'm not sure I can change it.

 

[Solice2o0]

Are you running the server with Multicraft?

 

[brainbaobao]

Are you running the server with Multicraft?

Yes, prominecraft host runs multicraft as its interface. Is that relevant to the situation?

 

[Solice2o0]

Yes, cause they messed up and made your server start up with an unknown Java flag. "-Xss=2M" is not a real Java flag, so it is the reason why you cannot start your server.

 

[nallar]

Yes, cause they messed up and made your server start up with an unknown Java flag. "-Xss=2M" is not a real Java flag, so it is the reason why you cannot start your server.

It is a real flag, just it shouldn't be used.

 

[Solice2o0]

It is a real flag, just it shouldn't be used.

Hmm, it seems as though I have a little bit more learning to do when it comes to Java flags.