std.allocator needs your help

[Rainer Schuetze]

On 24.09.2013 23:05, Andrei Alexandrescu wrote:
>> Taking the current array implementation as an example, the deltas are
>> computed before the actual GC lock happens inside gc_extend which means
>> that the second of two concurrent requests leads to overallocation.
>
> (I'm confused - which array implementation?)

I mean the dynamic array implementation in rt.lifetime.

> Does this qualify as an
> implementation bug, or are you referring to the case where the void[]
> being reallocated is being shared?

Yes, I'm referring to a shared void[], e.g. strings which use immutable 
shared buffers that you can still append to if you are not stomping 
other data.

Appending to it does not need a lock for the whole operation, but only 
an atomic operation when adding to the stored size (though the 
implementation uses a synchronized block to change the size).