[gclist] Fragmentation issues

[sanjay@pa.dec.com]

Hi,

I was wondering what people's experience has been with memory fragmentation
in garbage collected systems.  In particular, conservative collectors
might like to use certain allocation mechanisms to allow them to easily
identify pointers to object interiors.  (For example, all objects on a
page might have to have the same size.)

Does anybody have any ideas/anecodes/experiment results about the impact
of such decisions on overall memory fragmentation?

I realize that this is kind of a dangerous question because it might
provoke the precise/conservative GC war again.  It would be nice if
that does not happen ---  I think most of us understand that a precise
compacting collector will reduce fragmentation, but will lose a fair
bit of memory to a semi-space (at least for the youngest generation.)

Cheers,
-Sanjay Ghemawat