the VM ( Linux Contos 7 ) memory was group up very fast

I try to use dotnetty by websocket project but have a trouble.
I recevice some sub msg by client,then push lost of data msg back.
My Code Like This:
`List temp=new List(); `
`//------- add Channel in temp --------// `

`//------- input msg in Queue --------//`

`//-----ConcurrentQueue TryDequeue msg ---- //`

`Parallel.ForEach(temp, sc=>`
` {`
` sc.WriteAndFlushAsync(new TextWebSocketFrame(msg ));`

`}); `
The result is the VM ( Linux Contos 7 ) memory was group up very fast.
If remove `sc.WriteAndFlushAsync(new TextWebSocketFrame(msg ))` then memory is Ok.
It's some wrong when I use dotnetty?