It's because there isn't a compacting garbage collector running. The core is C/C++, so it relies on the OS allocator to keep memory from becoming fragmented. Th

It's because there isn't a compacting garbage collector running. The core is C/C++, so it relies on the OS allocator to keep memory from becoming fragmented. The OS allocators are good, but they aren't that good. In a browser you're constantly allocating and freeing large amounts of memory, so you're going to end up with some holes. Its usage pattern is way different than most applications because it's used like Google finally designed it: as a window into a bunch of different processes.