[gclist] ref-counting performance cost
Tue, 5 Sep 2000 01:19:51 -0700
| But this allocation cost would also be paid in a non-compacting
| or conservative mark-and-sweep, not just reference counting
| (i.e., it is not a unique problem to RC unlike the problems
| of space, time and cycles).
Indeed, that is true. But it's a problem that cannot be fixed for RC,
whereas it is relatively easy to adapt the mark/sweep story to do
compaction. (Mind you, compaction involves changing pointers, which
is hard in a concurrent setting.)
| To quote some advantages of RC from the GC Book of Jones & Lins:
Don't get me wrong! I'm *not* knocking RC! It's an elegant technique with
many advantages, as you enumerate. I was saying "people often
seem to ignore the allocation cost of non-compacting techniques", not
"the allocation costs of non-compacting techniques make them useless".