I notice that with the current client in puzzle 670 the memory usage is steadily growing.
With only mutates and wiggles the size has grown from 540 Mb to 730 Mb at the time of writing in a matter of a few hours. I cannot explain this with temporary storage needs. Last time the client crashed at 795 Mb.
I am anticipating it will crash again at that point this time. We have seen this particular behaviour before. A few months ago I reported on a memory leak which I think has not been fixed yet.