I think we're talking different scales here. At the scale of things that are roughly cache sized your point makes sense. The big concern about pauses is mostly coming from users with heaps in the 10s of GB and it's pretty unlikely on a PC you'll have more than 100MB of L2.
When it comes to designing the data structures your app uses you have a point but I think it's not directly to your app or runtime's policy for reclaiming freed objects. This does raise an idea that hadn't occurred to me before though: once you have a generational moving collector you may actually get virtuous cache effects because your nursery is densely packed with live objects.
...
Ok, it turns out that this has not only been studied a little but but at least PyPy tried this at one point (I looked at the code but couldn't find it).
When it comes to designing the data structures your app uses you have a point but I think it's not directly to your app or runtime's policy for reclaiming freed objects. This does raise an idea that hadn't occurred to me before though: once you have a generational moving collector you may actually get virtuous cache effects because your nursery is densely packed with live objects.
...
Ok, it turns out that this has not only been studied a little but but at least PyPy tried this at one point (I looked at the code but couldn't find it).
http://books.google.com/books?id=zVbbkWnxDP8C&lpg=PA99&ots=1...
http://pypy.readthedocs.org/en/latest/garbage_collection.htm...