std.container.Array/RefCounted(T) leaking memory?

Jesse Phillips jessekphillips+D at
Thu Jan 13 14:25:19 PST 2011

Thanks very nice info, just two guys babbling about things they've only read I guess, but you seem much better informed.

Steven Schveighoffer Wrote:

> I think all memory is allocated/deallocated from the OS via the sbrk/brk  
> system call:
>         brk()  and  sbrk()  change  the  location  of  the program break,  
> which
>         defines the end of the process's data segment (i.e., the program   
> break
>         is the first location after the end of the uninitialized data  
> segment).
>         Increasing the program break has the effect of allocating memory to  
> the
>         process; decreasing the break deallocates memory.
> So you can only ever add to the *end* of memory, and you can only ever  
> deallocate from the *end*.  And the OS doesn't ever just jump in and claim  
> memory, you have to tell it that you are deallocating memory.
> Which means, if you say allocated 100MB, and wanted to deallocate the  
> first 99MB, you still couldn't release any back to the OS.
> A moving GC would allow for more memory to be freed, but we aren't there  
> yet.
> Of course, I could be completely wrong about all this, I've never really  
> used sbrk or brk :)
> -Steve

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