[chuck-users] GC vs real-time (was Getting Started with ChucK)

[Hans Aberg]

On 22 Jul 2009, at 17:16, Robert Poor wrote:

>> <snip> The problem is not getting the GC fast enough, but they tend  
>> to do collecting at a specific time, when the whole program sort of  
>> halts.
>
> Once upon a time, I worked at a company called Lucid.  We made  
> Common Lisp Compilers.  Prior to Lucid, most Lisp systems would  
> grind to a halt whenever a GC took place.  One of the major  
> contributions made by Patrick Solbavarro was an ephemeral garbage  
> collector for general-purpose computers[*]: every time you allocated  
> some memory, it did a little bit of reclamation.
>
> Moral of the story: Ephemeral GCs techniques are mature, widely  
> understood and are exactly what's needed in a real-time environment.

So is the theory, but the comp.compilers thread mentioned some  
practical problems. If you want to collect little by little you need  
some large buffers, and tracing can cause virtual memory swaps on  
modern systems.

But if you you one which is tested and can guarantee no delays in the  
programming threads, let's hear.

   Hans