After running a world completely stable for about 2 weeks I started having, roughly twice daily , a massive spike in RAM, CPU and HDD usage.  RAM usage would go from ~500mb to more than 5gb usage eventually using up all the RAM the computer has. 

The HDD would start thrashing, possibly because it was using Virtual Memory.              

The computer would be mostly unusable at this point so it was hard to capture any information but I did manage to capture the screenshot below at the point of the crash. 

I "solved" this problem by running the Ubuntu version of BDS on the exact same hardware and using the exact same world.  Apart from the lower performance of Linux BDS (as noted elsewhere) I have not had a single issue.