My server identifier is: xenogm001
I am wondering if your Managed Linux configuration has swap enabled or disabled. I am running into a memory leak issue where the server process is terminating, when it reaches the hard defined limit defined by the Garry's Mod game engine. These are caused by mostly unavoidable factors. And yes is hidden by set auto-restarts.
From past experiences with a similar version of the source engine, swap is utilized as extra memory. Memory leaks are swapped at map change to free up more physical memory which can be used for other purposes. I was able to increase server up-times using this very method, so a different server could stay populated throughout the night. Does Garry's Mod work the same way?