[xmlp] the recent garbage collector performance improvements

[dsimcha]

On Wednesday, 1 February 2012 at 23:43:24 UTC, H. S. Teoh wrote:
> Out of curiosity, is there a way to optimize for the "many small
> allocations" case? E.g., if a function allocates, as temporary 
> storage,
> a tree with a large number of nodes, which becomes garbage when 
> it
> returns. Perhaps a way to sweep the entire space used by the 
> tree in one
> go?
>
> Not sure if such a thing is possible.
>
>
> T

My RegionAllocator is probably the best thing for this if the 
lifetime is deterministic as you describe.  I rewrote the Tree1 
benchmark using RegionAllocator a while back just for comparison. 
  D Tree1 + RegionAllocator had comparable speed to a Java version 
of Tree1 run under HotSpot.  (About 6 seconds on my box vs. in 
the low 30s for Tree1 with the 2.058 GC.)

If all the objects are going to die at the same time but not at a 
deterministic time, you could just allocate a big block from the 
GC and place class instances in it using emplace().