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February 23, 2012
D runtime Garbage Collector details
I am looking for the details on D Garbage Collection 
implementation. I will much appreciate if someone suggests the 
answers or give some links to existing documentation clarifying 
the following points:

1. Is it Mark-n-Sweep or copy or generational collector or simple 
reference counting? Or anything else? Any documentation on this 
would be very helpful

2. Sun/Oracle JVM publishes a number of counters in shared memory 
so that user may easily monitor the memory usage and the GC 
statistics real-time without affecting the application (and 
without modifying the application). Is there anything similar for 
D GC?

3. Is there any performance tests of D GC efficiency? Is it 
possible to write GC-predictable code (without manual 
allocate/free) or at least do something like System.gc()?
February 24, 2012
Re: D runtime Garbage Collector details
On 24 February 2012 12:49, Vadim <vadim.goryunov@gmail.com> wrote:
> I am looking for the details on D Garbage Collection implementation. I will
> much appreciate if someone suggests the answers or give some links to
> existing documentation clarifying the following points:
>
> 1. Is it Mark-n-Sweep or copy or generational collector or simple reference
> counting? Or anything else? Any documentation on this would be very helpful
>
> 2. Sun/Oracle JVM publishes a number of counters in shared memory so that
> user may easily monitor the memory usage and the GC statistics real-time
> without affecting the application (and without modifying the application).
> Is there anything similar for D GC?
>
> 3. Is there any performance tests of D GC efficiency? Is it possible to
> write GC-predictable code (without manual allocate/free) or at least do
> something like System.gc()?

I don't know the answers to 1 or 2, but I know that there is a GC
class with a bunch of methods on it for controlling the GC, including
enabling and disabling it and getting GC-allocated memory. Whether
that helps you write GC predictable code - I don't know, garbage
collection is mostly a black art to me :-)

--
James Miller
February 24, 2012
Re: D runtime Garbage Collector details
On Feb 23, 2012 6:50 PM, "Vadim" <vadim.goryunov@gmail.com> wrote:
>
> I am looking for the details on D Garbage Collection implementation. I
will much appreciate if someone suggests the answers or give some links to
existing documentation clarifying the following points:
>
> 1. Is it Mark-n-Sweep or copy or generational collector or simple
reference counting? Or anything else? Any documentation on this would be
very helpful
>
> 2. Sun/Oracle JVM publishes a number of counters in shared memory so that
user may easily monitor the memory usage and the GC statistics real-time
without affecting the application (and without modifying the application).
Is there anything similar for D GC?
>
> 3. Is there any performance tests of D GC efficiency? Is it possible to
write GC-predictable code (without manual allocate/free) or at least do
something like System.gc

There is quite a lot of info in the mailing list.  Off of the top of my
head I know it is a mark and sweep.  There is someone who did their Phd on
GC in D and he did a fairly good analysis of the current situation.

And as the fellow before me said, there is a garbage collector control.
February 24, 2012
Re: D runtime Garbage Collector details
Le 24/02/2012 00:49, Vadim a écrit :
> I am looking for the details on D Garbage Collection implementation. I
> will much appreciate if someone suggests the answers or give some links
> to existing documentation clarifying the following points:
>
> 1. Is it Mark-n-Sweep or copy or generational collector or simple
> reference counting? Or anything else? Any documentation on this would be
> very helpful
>

Mark and sweep, but do not copy and isn't generationnal.

> 2. Sun/Oracle JVM publishes a number of counters in shared memory so
> that user may easily monitor the memory usage and the GC statistics
> real-time without affecting the application (and without modifying the
> application). Is there anything similar for D GC?
>

You should ask the system for thoses infos.

> 3. Is there any performance tests of D GC efficiency? Is it possible to
> write GC-predictable code (without manual allocate/free) or at least do
> something like System.gc()?

Its performance are quite poor ATM, it is getting better, but still not 
as effeiscient as java's GC for example. You could disable it using the 
class GC on critical period of time, so you'd know when it run and when 
it cannot trigger itself. D allow also to manage memory manually, and if 
you don't generate garbage, GC will not trigger.
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