either me or GC sux badly (GC don't reuse free memory)

[ketmar via Digitalmars-d]

On Wed, 12 Nov 2014 12:05:25 +0000
thedeemon via Digitalmars-d <digitalmars-d at puremagic.com> wrote:

> On Wednesday, 12 November 2014 at 11:05:11 UTC, ketmar via 
> Digitalmars-d wrote:
> >   734003200
> > address space" (yes, i'm on 32-bit system, GNU/Linux).
> >
> > the question is: am i doing something wrong here? how can i 
> > force GC to stop eating my address space and reuse what it 
> > already has?
> 
> Sure: just make the GC precise, not conservative. ;)
> With current GC implementation and array this big chances of 
> having a word on the stack that looks like a pointer to it and 
> prevents it from being collected are almost 100%. Just don't 
> store big arrays in GC heap or switch to 64 bits where the 
> problem is not that bad since address space is much larger and 
> chances of false pointers are much smaller.
but 'mkay, let's change the sample a little:

  import core.memory;
  import std.stdio;

  void main () {
    uint size = 1024*1024*300;
    for (;;) {
      auto buf = new ubyte[](size);
      writefln("%s", size);
      size += 1024*1024*100;
      GC.free(GC.addrOf(buf.ptr));
      buf = null;
      GC.collect();
      GC.minimize();
    }
  }

this shouldn't fail so soon, right? i'm freeing the memory, so... it
still dying on 1,887,436,800. 1.7GB and that's all? this can't be true,
i have 3GB of free RAM (with 1.2GB used) and 8GB of unused swap. and
yes, it consumed all of the process address space again.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: not available
URL: <http://lists.puremagic.com/pipermail/digitalmars-d/attachments/20141112/26482b68/attachment.sig>