Status of getting CDGC into druntime

[Darren via Digitalmars-d]

On Monday, 2 June 2014 at 19:04:05 UTC, Sean Kelly wrote:
>
> What I did at the time I created the CDGC branch was diff our GC
> now vs. the code from when Druntime was created (the SVN repo on
> dsource.org).  It shouldn't be more than a bunch of busywork for
> someone to figure out which changes are relevant and apply them,
> but it's busywork no one has wanted to do yet.

I think the plan was to incrementally evolve the GC towards the 
CDGC. Probably the 'right' thing to do but it requires more 
patience (and a deeper understanding of the GC code). Judging by 
the commit history the effort does appear to have slowed down. 
Perhaps there's activity taking place that's not visible on 
github.

I'm personally really interested in the progress of this effort - 
in particular removing the global lock on allocations. My primary 
experience is with Java, which is far more profligate with object 
allocation than D, but single-threaded object allocation was one 
of the biggest performance killers for certain types of 
application. We had 4-cpu servers (back when that was a lot) with 
1 red-hot processor and 3 idle ones due to contention on memory 
allocation.

I'd also like to echo Leandro regarding configurable GC. There is 
no one-size-fits-all for applications. Interactive applications 
favour low-latency over throughput, while a long-running batch 
process wants throughput and doesn't care so much about long 
pauses. Being able to tune Java's GC at runtime allowed me to 
turn a 90 minute batch process into 12 minutes with zero code 
changes. A real lifesaver.